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[ES] La industria del automóvil está regulada por diferentes normativas en todo el mundo por sus emisiones de GEI que salen de los tubos de escape de los vehículos. Recientemente, teniendo en cuenta el objetivo a largo plazo de 2050 de alcanzar la neutralidad del carbono, se está poniendo un gran énfasis en el cambio a los vehículos eléctricos. En Europa, concretamente, el Green Deal propuesto por la Comisión Europea ha prohibido la venta de turismos con motor de combustión interna a partir de 2035. Asimismo, en Estados Unidos se ha fijado el objetivo de vender el 50% de los vehículos eléctricos en 2030. Estas políticas se aplican denominando a los VE como vehículos de cero emisiones (ZEV), basándose únicamente en sus emisiones de tanque a rueda. Sin embargo, si se tienen en cuenta las emisiones de todo el ciclo de vida, los VE tienen una cuota de emisiones considerable, y mucho mayor cuando se evalúan en ciclos de conducción real. La fuente de producción de electricidad es muy importante, ya que determina las emisiones del pozo al depósito, que pueden ser incluso superiores a las del combustible convencional. Por lo tanto, este estudio se lleva a cabo para estimar el potencial de reducción de las emisiones de CO2 de diferentes tecnologías de tren motriz para autobuses y turismos en ciclos de conducción real y considerando el ciclo de vida global. El software GT suite se utiliza para la evaluación del consumo de combustible en ciclos de conducción real utilizando información de velocidad del vehículo basada en GPS. Mientras que para la evaluación del ciclo de vida se utiliza la huella de emisiones del software de ACV GREET. Dado que la prohibición de la venta de vehículos con motor de combustión interna se aplica al sector de los turismos, se evalúan tres configuraciones de la cadena cinemática: Diesel convencional, híbrido y SUV eléctrico, así como el uso de combustible electrónico (como OMEx) en las cadenas cinemáticas ICE convencionales e híbridas. A continuación, [EN] The automotive industry is regulated by different regulations across the world for its GHG emissions coming out from the tailpipes of the vehicles. Recently, keeping in mind the 2050 long term goal to reach carbon neutrality, a huge emphasis is being given towards the shift to electric vehicles. In Europe specifically, the Green Deal proposed by the EU commission has put a ban on Internal Combustion Engine passenger cars¿ sale from 2035. Also, in the United States of America a target of 50% Electric Vehicle sales is set for 2030. These policies are implemented by referring EVs as Zero Emission Vehicles (ZEVs), based on its Tank-to-Wheel emissions only. However, if the entire life cycle emissions are considered, the EVs have a considerable share of emissions, and much higher when evaluated on Real Drive cycles. The source of electricity production is very important as it determines the Well-to-Tank emissions, which can be even higher than that of the conventional fuel. Hence, this study is carried out to estimate the CO2 emission reduction potential of different powertrain technologies for buses and passenger cars on real drive cycles and considering the overall life cycle. The GT suite software is used for the assessment of the fuel consumption on Real Drive cycles using GPS based vehicle speed information. While for the life cycle evaluation emission footprint from the LCA software GREET is used for the evaluation. As the ICE ban on new sales is done for the passenger car sector, evaluation is done of three powertrain configurations: Conventional Diesel, Hybrid and Electric SUV as well as using e-fuel (such as OMEx) in the Conventional and Hybrid ICE powertrains. Which is then evaluated for its emission reduction potential in the US as well as EU, according to the set targets in both regions. Further, the current automotive fleet is used for both the US and EU to compare the emission reduction potential considering the change in the fleet by the integration of

[ES] A medida que los efectos del calentamiento global se hacen más severos, el estudio de alternativas para tratar de frenarlos, o incluso detenerlos, aumenta su importancia. El sector de transporte es uno de los principales contribuyentes a los insidiosos gases de efecto invernadero (GEI), y como tal este sector debe estar a la vanguardia del desarrollo de estrategias que reduzcan las emisiones globales. Por otro lado, los entes reguladores de emisiones se han vuelto más estrictos con cada nueva iteración de normativa, y actualmente, nos encontramos en la cúspide de nuevas normativas que podrían no dejar cabida para los motores de combustión interna en años posteriores al 2025. La tendencia para los vehículos ligeros es la electrificación. Sin embargo, la electrificación completa del parque automotor tomará tiempo, inversión de capital y adaptación del consumidor debido a que los vehículos eléctricos (VE) todavía presentan altos costos de producción, menos puntos de carga, un rango de distancia menor, y un tiempo de carga mayor que sus contrapartes de combustión interna. En el caso de las flotas de vehículos pesados, estas limitaciones continúan representando un impedimento para la adopción de los Ves a causa de las demandas de rentabilidad, peso y distancia requeridas. Alternativas diferentes a la conversión a eléctricos deben también ser exploradas y serán tremendamente importantes en regiones donde la red eléctrica se conforme de fuentes de generación desfavorables para el medio ambiente, se encuentre en mal estado o desarrollo, o el costo de substitución de vehículos sea prohibitivo. En tal sentido, el uso de combustibles alternativos que no contribuyan hacia los gases de efecto invernadero gana relevancia a medida que las políticas para lograr cero emisiones entran en vigor alrededor del mundo. El estudio de combustibles que puedan tener propiedades energéticas similares a las de los combustibles convencionales (diésel y gasolina), pero con menores emisiones, [EN] As the effects of global warming become more dire, the study of alternatives to try to delay it, or even stop it, become increasingly important. The transport sector is one of the main contributors to the insidious greenhouse gases (GHG), and as such should be at the forefront of the development of strategies that reduce global emissions. On the other side, emissions regulators have become stricter with every new iteration of normative, and currently we are on the cusp of new rulings that could potentially leave no room to the use of internal combustion engines beyond 2025. The tendency for light-duty vehicles is to become electrified. However complete electrification of the automotive park will take time, capital investment and consumer adaption since electric vehicles (EV) still present higher production costs, less charging stations, a shorter range, and a longer time to replenish its energy than internal combustion vehicles. In the case of heave-duty fleets these limitations still represent a significant impediment for the adoption of EVs due to their rentability, weight and distance demands. Alternatives different to electrification should also be explored and will be tremendously important in regions where the electric grid is not comprised of mainly green sources, is not as well developed, or the cost of vehicle substitutions is prohibitive. In that sense, the use of alternative fuels that do not contribute to greenhouse gases is gaining relevance as policies to move to zero emissions come into force across the world. The study of fuels that can have similar energetic properties as conventional fuels (diesel and gasoline), but with less engine-out emissions and net-zero production emissions, while remaining usable as drop-in substitutes where neither the engine nor the drivetrain has to be modified becomes an insightful endeavor. Having said the above, the present work is dedicated to the study of the effect of e-fuels like OMEx, methanol and methane on

[ES] La producción de vehículos híbridos y eléctricos (HEV & BEV) ha experimentado un crecimiento exponencial los últimos años y se sitúan como la primera opción para sustituir en un futuro a corto plazo a los vehículos diésel o gasolina gracias al gran impulso de los gobiernos estatales centrados en una transición ecológica hacia el objetivo de cero emisiones. Es por ello por lo que los problemas asociados a este tipo de tecnologías han adquirido gran importancia y las grandes compañías automovilísticas han puesto los focos en ellos para tratar de mejorar la seguridad y eficiencia de sus vehículos. Uno de los grandes problemas de la tecnología eléctrica es el fenómeno de Thermal Runaway, un fenómeno todavía bastante desconocido inherente a los elementos de almacenamiento de energía eléctrica actuales y que consiste en un aumento de la temperatura del elemento provocado por reacciones exotérmicas que se generan en él, causadas precisamente por la elevada temperatura, entrando en una retroalimentación térmica que finaliza cuando se consumen todos los materiales reactivos. Este proceso puede originar, en el peor de los casos, la combustión del módulo de baterías afectado y en consecuencia poner en peligro a los usuarios de estos vehículos. En este trabajo, por tanto, se comienza el estudio tanto numérico como experimental del proceso de Thermal Runaway en baterías de litio 18650 orientadas a vehículos híbridos y eléctricos con el fin de llegar a comprender este fenómeno profundamente y poder mejorar la seguridad de los módulos de baterías utilizados como unidad de potencia. El estudio numérico se realiza mediante dinámica de fluidos computacional (CFD) con el software Converge CFD y se centra en dos tipos de simulaciones: simulaciones termofluidodinámicas, que toman en cuenta los campos de temperaturas en el dominio incluso considerando posibles procesos de combustión; y simulaciones fluidodinámicas donde la modelización se centra en los procesos físicos de producción, [EN] Hybrid and electric vehicles (HEV & BEV) production have experienced an exponential growth last couple of years and are the most popular option for replacing diesel and gasoline vehicles in short term thanks to the great push the governments, focused on a green transition to the zero emissions objective, are giving to them. Due to this, big automotive companies are putting their efforts in solving the most common problems related to this technology to improve the safety and efficiency of their vehicles. One of the biggest problems of the electric technology is the Thermal Runaway phenomena, a still quite misunderstood phenomena inherent to current electric batteries which consists in a temperature increase caused by exothermic reactions generated inside them, originated by this high temperature and starting so an uncontrolled thermal positive feedback that ends when all the reagents are consumed. This process can trigger, at worst, the combustion of the damaged battery module, compromising the safety of these vehicles¿ users. Therefore, this Master thesis consists in establishing the bases of a both numerical and experimental study of the Thermal Runaway process in lithium-ion 18650 batteries used in hybrid and electric vehicles with the purpose of comprehend deeply this phenomenon and be able to improve the security of their battery modules. In one hand, the numerical study is done by computational fluid dynamics (CFD) with the software Converge CFD and is focused on two types of simulations: Thermal fluid dynamic simulations, which consider temperature fields in the computational domain and including modelling of possible combustion processes; and fluid dynamic simulations which are focused in the modelling of the physical processes of production and ejection of gases in a damaged and isolated lithium battery. In the results of these simulations are analysed the temperatures reached in a battery module with a battery cell in Thermal Runaway, the mix of the ej

[ES] El principal objetivo de este proyecto es, profundizar en la comprensión de un nuevo modo de combustión basado en mezclas parcialmente premezcladas en motores de encendido por compresión haciendo uso de técnicas ópticas. Se pretende así, contribuir en la búsqueda de soluciones para reducir las diferentes desventajas asociadas a los nuevos modos de combustión encontrados durante la revisión bibliográfica. Existen varios objetivos secundarios, como son el montaje de un sistema de cámaras rápidas para la captura de imágenes, el posterior tratado de la información recogida tanto por los equipos ópticos y los elementos de medida para el estudio de la combustión.

[ES] La temperatura de las baterías juega un rol importante para el buen desempeño de los vehículos electrificados (BEV, PHEV y HEV). Un adecuado manejo térmico permite alargar el ciclo de vida y rendimiento de las mismas. El presente trabajo tiene como objetivo la regulación térmica de las baterías tipo ion-litio por medio de un sistema de placas refrigeradoras con mini canales circulares por donde se hace pasar un refrigerante a través de ella. Se realizará el CAD utilizando Solid Works para el diseño del sistema de baterías y placas de refrigeración. Posteriormente, se realizará la transformación a un modelo 2D donde se evaluará la transferencia de calor, perdidas de carga en tuberías entre otros parámetros. Se estudiará la influencia de diferentes geometrías, disposiciones, flujos másicos de líquido refrigerante en los mini canales de las placas de enfriamiento, entre otros parámetros. El software seleccionado es GT-Suite de Gama Technologies ya que permite resolver las reacciones electroquímicas-térmicas de las baterías. Los resultados muestran que para un número igual de mini canales, mismo flujo másico y diferentes diámetros la variación de la temperatura en el módulo es despreciable, sin embargo, la caída de presión se ve disminuida conforme el diámetro crece. Un aumento del caudal del refrigerante reduce la temperatura del sistema placa-baterías a expensas de una caída de presión más elevada y por ende un mayor consumo de potencia para la bomba. Con los datos recolectados se ha llegado a la conclusión que una placa con 10 mini canales y un caudal másico promedio de 2.5 x 10-4 kg. s-1 es ideal para mantener la temperatura de la batería AMP20 dentro de un rango deseable de 25ºC a 40ºC para garantizar el buen desempeño., [EN] The temperature of the batteries plays an important role in the performance of electrified vehicles (BEVs, PHEVs and HEVs). A proper thermal management allows extending the life cycle and performance of the batteries. The present work aims at the thermal regulation of lithium-ion batteries by means of a system of cooling plates with mini circular channels through which a coolant is passed through it. The CAD will be made using Solid Works for the design of the battery system and cooling plates. Subsequently, the transformation will be made to a 2D model where heat transfer, pressure drops in pipes and other parameters will be evaluated. The influence of different geometries, arrangements, mass flows of coolant in the mini channels of the cooling plates, among other parameters, will be studied. The selected software is GT-Suite from Gama Technologies as it allows to solve the electrochemical-thermal reactions of the batteries. The results show that for an equal number of mini-channels, same mass flow and different diameters the temperature variation in the module is negligible, however, the pressure drop decreases as the diameter increases. An increase in the coolant flow rate reduces the temperature of the plate-batteries system at the expense of a higher pressure drop and therefore a higher power consumption for the pump. With the data collected it has been concluded that a plate with 10 mini-channels and an average mass flow rate of 2.5 x 10-4 kg. s-1 is ideal for maintaining the temperature of the AMP20 battery within a desirable range of 25ºC to 40ºC to ensure good performance.

[ES] Estudios previos han demostrado el potencial de emplear la estrategia de combustión dual-mode dual-fuel juntamente con la hibridación, para la reducción de emisiones contaminantes, respecto de una combustión tradicional de un motor diésel en camiones. El objetivo principal del presente trabajo reside en analizar la respuesta transitoria del motor MDE8 de Volvo operando en este modo de combustión en un camión con arquitectura de hibridación serie, empleando como combustibles el diésel y la gasolina. Para ello, con el programa informático Matlab, se representa la evolución de diversas variables para distintas cantidades de mercancía transportada por el camión, en diferentes puntos de operación del motor. Además, se estudia el tiempo de respuesta del motor en las distintas transiciones entre los puntos de operación, a partir de la evolución temporal del par. También, se estima el comportamiento del turbocompresor para condiciones estacionarias y transitorias, a partir de otras variables cuyo valor se conoce. Así, se obtienen los caudales másicos que circulan por el compresor y la turbina, las potencias y los rendimientos. Finalmente, los resultados muestran que la respuesta transitoria, en general, difiere menos del comportamiento estacionario conforme mayores son las temperaturas alcanzadas. Este fenómeno se ve pronunciado por el hecho de transportar una mayor mercancía, ya que el motor térmico se enciende con una frecuencia superior para recargar las baterías, así como por el efecto del calentamiento del motor a medida que transcurre el ensayo., [EN] Previous studies have shown the potential of using the dual-mode dual-fuel combustion strategy together with hybrid electric powertrains to reduce polluting emissions compared to a traditional combustion of a diesel engine in trucks. The main objective of this work is to analyze the transient response of the Volvo MDE8 engine operating in this combustion mode in a truck with serial hybrid architecture, using diesel and gasoline as fuels. To achieve this, the Matlab computer program was used so as to get a representation of the evolution of different variables for different truck loads at different operating points of the engine. In addition, the response time of the engine at different operating point transitions is studied, based on the temporal evolution of the torque. Furthermore, the behavior of the turbocharger under stationary and transient operating conditions is estimated from other variables whose value is known. Thus, the mass flow rate that circulates through the compressor and the turbine, as well as power and efficiency are obtained. Finally, the findings reveal that the transient response, in general, differs less from the stationary behavior as higher temperatures are reached. This phenomenon is increased by the effect of transporting less goods, since the heat engine is turned on at a lower frequency to recharge the batteries, as well as the effect of engine heating as the test progresses.

[ES] Históricamente, el sector del transporte de servicio mediano y pesado ha sido desafiado por las regulaciones de emisiones que se han impuesto a lo largo de los años, lo que requirió intensificar el esfuerzo de investigación con el objetivo de avanzar en el desarrollo tecnológico para ofrecer una opción que cumpla con las normas a un precio similar para el propietario. No obstante, la reciente introducción de la normativa EUVI ha requerido la adición de un complejo sistema de postratamiento, agregando nuevos costes fijos al producto, así como costes operativos con el consumo de urea. Este avance fue necesario debido a la limitación de la combustión diésel convencional que no puede desacoplar las altas emisiones de NOx y la eficiencia. Esta limitación tecnológica ha impulsado la investigación sobre diferentes conceptos de combustión que podrían mantener niveles de eficiencia similares a los de la combustión diésel controlando la formación de emisiones durante el proceso de combustión. Entre las diferentes soluciones que han ido apareciendo a lo largo de los años, se demostró que la Ignición por Compresión Controlada por Reactividad (RCCI por sus siglas en inglés) tiene una ventaja competitiva debido a su mejor controlabilidad, alta eficiencia y bajas emisiones de hollín y NOx. A pesar de sus beneficios, la extensión de RCCI a la operación de mapa completo ha indicado limitaciones importantes como gradientes de presión excesivos a alta carga, o alta inestabilidad de combustión y productos no quemados a baja carga del motor. Recientemente, se introdujo el concepto de combustión Dual-Mode Dual-Fuel (DMDF) como un intento de resolver los inconvenientes de la combustión RCCI manteniendo sus ventajas. Los resultados preliminares obtenidos en un motor mono cilíndrico (SCE por sus siglas en inglés) han demostrado que el DMDF puede alcanzar niveles de eficiencia similares a los de la combustión diésel convencional al mismo tiempo que favorece niveles ultra bajos de hollín, [CA] Històricament, el sector del transport de servei mitjà i pesat ha sigut desafiat per les regulacions d'emissions que s'han imposat al llarg dels anys, la qual cosa va requerir intensificar l'esforç d'investigació amb l'objectiu d'avançar en el desenvolupament tecnològic per a oferir una opció que complisca amb les normes a un preu similar per al propietari. No obstant això, la recent introducció de la normativa EUVI ha requerit l'addició d'un complex sistema de postractament, agregant nous costos fixos al producte, així com costos operatius amb el consum d'urea. Aquest avanç va ser necessari a causa de la limitació de la combustió dièsel convencional que no pot desacoblar les altes emissions de NOx i l'eficiència. Aquesta limitació tecnològica ha impulsat la investigació sobre diferents conceptes de combustió que podrien mantindre nivells d'eficiència similars als de la combustió dièsel controlant la formació d'emissions durant el procés de combustió. Entre les diferents solucions que han anat apareixent al llarg dels anys, es va demostrar que la Ignició per Compressió Controlada per Reactivitat (RCCI per les seues sigles en anglés) té un avantatge competitiu a causa de la seua millor controlabilitat, alta eficiència i baixes emissions de sutge i NOx. Malgrat els seus beneficis, l'extensió del RCCI a l'operació de mapa complet ha indicat limitacions importants com a gradients de pressió excessius a alta càrrega, o alta inestabilitat de combustió i productes no cremats a baixa càrrega del motor. Recentment, es va introduir el concepte de combustió Dual-Mode Dual-Fuel (DMDF) com un intent de resoldre els inconvenients de la combustió RCCI mantenint els seus avantatges. Els resultats preliminars obtinguts en un motor mono-cilíndric (SCE per les seues sigles en anglés) han demostrat que el DMDF pot aconseguir nivells d'eficiència similars als de la combustió dièsel convencional al mateix temps que afavoreix nivells ultra baixos de sutge i NOx. Si bé, els requisits, [EN] The medium and heavy-duty transport sector was historically challenged by the emissions regulations that were imposed along the years, requiring to step up the research effort aiming at advancing the product development to deliver a normative compliant option at similar price to the owner. Nonetheless, the recent introduction of EUVI normative have required the addition of a complex aftertreatment system, adding new fixed costs to the product as well as operational costs with the urea consumption. This breakthrough was required due to the limitation of the conventional diesel combustion which cannot decouple high NOx emissions and efficiency. This technological limitation has boosted the investigation on different combustion concepts that could maintain similar efficiency levels than the diesel combustion while controlling the emission formation during the combustion process. Among the different solutions that have appeared along the years, Reactivity Controlled Compression Ignition (RCCI) was demonstrated to have a competitive edge due to its better controllability, high efficiency and low soot and NOx emissions. Despite the benefits, the extension of RCCI to full map operation has presented significant limitations, as excessive pressure gradients at high load and high combustion instability and unburned products at low engine load. Recently, Dual-Mode Dual-Fuel (DMDF) combustion concept was introduced as an attempt of solving the drawbacks of the RCCI combustion while maintaining its advantages. The preliminary results obtained in single cylinder engine (SCE) have evidenced that DMDF can achieves similar efficiency levels than those from conventional diesel combustion while promoting ultra-low levels of soot and NOx. Albeit, the boundary condition requirements are hard to fit in the operating range of commercial air management system as well as drawbacks like excessive HC and CO that still persists from low to medium load, which can be a challenge for the aft

[EN] Recent investigations show that there are different combustion strategies that promise to achieve higher efficiencies in internal combustion engines. Advanced combustion modes such as reactivity controlled compression ignition (RCCI) and dual-mode dual-fuel (DMDF) have proven to be able to achieve low NOx and soot engine-out emissions while being able to operate over the complete engine map. On another front, intensive research has been done in the fuels field. Oxygenated fuels, like oxymethylene dimethyl ethers (OMEx) and methanol, are of special interest because of their potential to reduce the soot emissions, while allowing to adjust parameters, such as EGR, to higher values to also reduce NOx emissions and avoid other problems like excessive in-cylinder peaks of pressure. In this research, the effects of diesel-methanol and OMEx-gasoline fuels were studied on a dual-mode dual-fuel (DFDM) multi-cylinder engine at 1800 rpm for various loads (25, 50, 80 and 100%). To do so, a dedicated calibration to optimize the brake thermal efficiency while trying to maintain NOx and soot emissions under EURO VI limitations was applied. Then, the combustion characteristics, performance and emissions results are compared to a base diesel-gasoline case. Boundary conditions (intake pressure, temperature and air mass) for each fuel combination where similar, with the exception of the premixed energy ratio, which was on average 20% lower for diesel-methanol. Each fuel combination was, weighted against each other by means of an merit function, where the fuel combination with the lowest value has the closest approximation to ideal BSFCeq, BSNOx, BSSoot, BSCO and BSHC targets. Results show that diesel-methanol presents no significant differences with respect to diesel-gasoline in terms of equivalent BSFCeq and NOx, while the substitution of diesel by OMEx in the dual-mode dual-fuel combustion has the potential of, although penalizing HC and CO emissions, not only achieving the EURO

[EN] The potential of plug-in hybrid electric vehicles (PHEV) to reduce greenhouse gas emissions highly depends on the vehicle usage and electricity source. In addition, the high costs of the battery pack and electric components suppose a challenge to the vehicle manufacturers. However, the internal combustion engine complexity can be reduced due to its lower use as compared to the no-hybrid vehicles. This work evaluates the use of a new opposed piston 2-stroke engine, based on rod-less innovative kinematics, in a series PHEV architecture based on rod-less innovative kinematics along different driving routes in Europe. A 0D-vehicle model fed with experimental tests is used. The battery size is optimized under homologation conditions for two different vehicle types. The optimum case is tested in several real driving conditions under different vehicle modes and battery states of charge. The main contribution of this work is the demonstration of the potential to reduce the vehicle CO2 emissions and cost with an innovative 2-stroke engine. The results show that 24 kWh is the optimum battery size for both vehicle platforms. Charge depleting mode shows 70% of CO2 tailpipe reduction in urban cycles and 22% in long travels compared to the no-hybrid version. Charge sustaining mode results show a CO2 tailpipe reduction of 20% in urban cycles and 2% in long distance travels with respect to the no-hybrid version. In spite of the CO2 contribution of the battery manufacturing, the results show a reduction of LCA CO2 emissions in 52% in charge depleting and 7% charge sustaining against the no-hybrid case.

[EN] Recent outlooks suggest a long-term relevance of internal combustion engines for both power generation and transportation. Nonetheless, stringent pollutant reduction requirements combined with new CO2 mandates draws a challenging scenario, requiring intensive research and development activities to develop and optimize combustion modes to fulfill these requirements. Among the recent advancements, the active pre-chamber ignition system has been considered as a potential alternative to achieve a highly efficient and clean combustion process. Its combustion development is dictated by the pre-chamber ignition system which will provides a high energy flow jet inside the main chamber to enable a multi-site oxidation of the global lean mixture. The comprehension and quantification of the flow and combustion characteristics of the pre-chamber are of utmost importance to optimize the engine operation and pre-chamber design. Nonetheless, restrictive space for instrumentation at experimental side requires alternative numerical methods to aid the quantification of the state parameters and combustion process of these systems. In this sense, this research proposes a novel methodology combining incylinder pressure measurement and 1-D simulations as a tool to determine the state, flow and combustion development of different active pre-chambers operating with natural gas in a heavy-duty engine for power generation. The methodology is developed considering 3 different pre-chamber geometries, operating at different spark timings and equivalence ratios. The results suggest that the methodology is able to quantify the state conditions prior to the spark discharge as well as the evolution of the combustion process by means of considering the perturbations of the mass flow from the pre-chamber inside the main chamber energy balance. Moreover, the methodology allowed to quantify variations of equivalence ratio as small as 0.1 and combustion durations variations of 1 CAD.

[EN] Highway transport sector is still expected to be dominated by internal combustion engines in the future, especially due to limitations in the introduction and applicability of full electrification for heavy-duty propulsive systems. Nonetheless, this sector is still under the objectives imposed in the roadmap towards carbon neutrality. For this, engine efficiency and low-emission combustion modes must be improved, and the introduction of synthetic fuels, low electrification levels and devices for engine optimization and energy management have proven to be a great advance towards these objectives. This work studies the application of an EGR e-pump for energy recovery and combustion optimization on a powertrain running on Dual-Mode Dual-Fuel combustion mode as a substitute of a complex dual route EGR system. The results include the evaluation of the impact of using energy recovery devices on combustion performance and emissions levels, as well as a numerical evaluation of driving conditions considering a medium-duty application in the transport sector under different driving scenarios. The results point out that the inclusion of the EGR e-pump can contribute to mitigate the drawbacks of removing the complex dual route system in terms of equivalent fuel consumption without greater impact in terms of emissions. Additionally, its application in mild hybrid platforms can promote a significant improvement in CO2 emissions, especially for urban areas (20% compared to a conventional powertrain based on HP EGR).

[EN] Low energy density fuels combined with low temperature combustion modes have demonstrated a great contribution to engine-out NOx and soot reduction. Additionally, synthetic fuels have become an important way of reaching carbon neutral utilization of hydrocarbon-based fuels and internal combustion engines. Specifically, poly-oxymethylene dimethyl ethers (OMEx) have demonstrated great advantages in combination with conventional fuels with higher energy content to compensate that aspect to reduce NOx emissions below the EU VI homologation normative while maintaining ultra-low soot emissions with a great benefit in CO2 emissions in a well-to-wheel basis. Nonetheless, the properties of this fuel in single-fuel combustion strategies are not thoroughly investigated in the literature. The objective of this work is to investigate the capabilities of OMEx fuel under conventional combustion modes compared to those of conventional diesel combustion. To do this, an experimental characterization under stoichiometric combustion has been carried out to evaluate the impact on engine hardware demand and total emissions. Additionally, a brief exploration under leaner conditions is performed. The results obtained from this work point out that, even under ultra-high EGR rates to reach high fuel-to-air ratios, OMEx fuel can emit ultra-low soot and NOx emissions with more than 90% reduction compared to diesel on engine out emissions. Under stoichiometric conditions, a significant increase appears on CO, UHC due to excessive usage of EGR and equivalent fuel consumption is penalized from 15% to 40% depending on the operating condition, but under slightly leaner conditions, a region where equivalent fuel consumption is improved with respect to CDC appears, and the four main pollutants investigated are almost EU VI compliant, exposing a very high potential for this fuel

[EN] Homogenous charge compression ignition engines have been studied as an alternative to the conventional diesel combustion to attain high efficiency with ultra-low NOx and soot emissions for a wide variety of fuels. However, its usage in real applications has been restricted due to the difficulties regarding combustion control and operating range extension. The modification of the fuel characteristics may be a pathway to solve the previous hurdles. Therefore, this research presents a relevant methodology to assess the fuel response to HCCI boundary conditions based on 0-D and 1-D modelling for detailed chemistry solution and state conditions definition, respectively. The results suggest that the methodology can predict the early stages of the fuel oxidation with good accuracy. For the objective of predicting the start of combustion, the best results are obtained using tabulated chemistry when investigating fuels that have pre reactions and a low temperature heat release. As the oxidation process progresses, the deviation of the pressure-temperature trajectory from non-reactive to reactive conditions after the low temperature heat release decreases the predictive capability to some extent. Nonetheless, the methodology outcomes are still valid as a qualitative metric for reactivity determination as well as the intermediate and high temperature ignition delay

[EN] The development of new piston geometries has shown great potential to achieve the low levels of soot emissions required by regulation. Thus, the present paper aims to characterize the influence of a new piston design over combustion process. It is characterized by the introduction of protrusions around the periphery of the bowl, evenly spaced. The performance of this geometry is compared to other geometries that have been extensively analyzed in literature, under similar operating conditions. To achieve this objective, a single cylinder optical compression ignition engine was used with full-quartz pistons rep resenting three bowl geometries: re-entrant, stepped lip and wave-stepped lip. Two optical techniques (OH* chemiluminescence and Natural Luminosity-NL) were applied for identifying the near stoichiometric zones and the differences in the combustion evolution. The flame movement was analyzed by applying the combustion image velocimetry (CIV) algorithms. In addition, an in-cylinder pressure analysis was performed for each piston at 4.5 bar and 7.5 bar IMEP and the differences in terms of Rate of Heat Release were highlighted. A more intense reverse flow was clearly identified when using wave protrusions inside the bowl. The stepped lip and wave-stepped lip bowl present faster late cycle oxidation with much near-stoichiometric zones than re-entrant piston

[EN] E-fuels are a very attractive way for improving the well-to-wheel emissions of CO 2 in internal combustion engines. In the particular case of compression ignition engines, the Oxymethylene dimethyl ether (OME X ), an e-fuel with nearly soot-free combustion under mixing-controlled conditions, is a good candidate for the replacement of fossil fuels. However, the Lower Heating Value of OME X is nearly half of the diesel fuel, which means that much longer injection durations are required in the real engine. In addition, the very low viscosity and lubricity of OME X can damage the injection system if used pure, but it can be an interesting fuel when blended with conventional diesel. Thus, the main objective of this paper is to evaluate the potential of OME X -diesel blends to bypass these OME X limitations whilst keeping low soot formation trends. For this purpose, a single cylinder optical diesel engine at part load was employed. The soot production for the different fuel blends was analyzed by applying three different high-speed imaging techniques: natural luminosity, flame spectroscopy and 2-color pyrometry. Natural luminosity analysis showed that the flame light intensity scales with diesel fraction up to 30% of diesel in the blend. The spectroscopy analysis has revealed that soot formation of OME X fuel is almost null. When blended with diesel at 50%, although soot formation is still lower than for pure diesel, higher soot levels are obtained in the last stages of the cycle as a consequence of the longer injections required.

[EN] Reactivity controlled compression ignition combustion showed great advantages in terms of NOx and soot emissions reduction, leading to virtually zero emissions. However, the average brake thermal efficiency of this concept is like that found with conventional diesel operation. The powertrain electrification using electric motors and battery packages appears as a potential solution to reduce the CO2 emissions. For this reason, several solutions for the powertrain electrification can be found currently in the market as the parallel, series and power split powertrain architectures. The aim of this work is to evaluate the hybrid architecture impact on the fuel consumption and emissions of a delivery truck (Volvo-FL) intended for urban and urban-rural applications. The truck equipped with a reactivity-controlled compression ignition diesel-gasoline engine is evaluated and compared against the conventional diesel case. In addition, to evaluate the impact of new e-fuels on the well-to-wheel CO2 emissions, a synthetic gasoline coming from carbon capture and green electricity is evaluated. The results show that hybridization allows reducing the tank-to-wheel CO2 emissions above 15% with the parallel hybrid set-up. The series and power split architectures show CO2 benefits of 12% with respect to the baseline diesel non-hybrid case. Using synthetic gasoline as low reactivity fuel allows to achieve a 50% well-to-wheel CO2 reduction in the P2 and 70% well-to-wheel CO2 reduction for the series and power split cases due to the higher average gasoline fraction used in the driving cycle

[EN] The electrification of propulsion systems in light passenger vehicles is essential to reach the objectives set by the different organizations that protect the environment. However, due to various aspects such as politician decisions, bad press, high powertrain production costs and a moderate reduction in energy consumption, purely electric vehicles are being a priority for several car manufacturers as well as for governments instead of hybrid vehicles. This article shows how hybrid electrification, using a low temperature combustion engine, is capable of reducing the energy consumption while drastically minimizing the particle matter (mainly soot) and NOx emissions, in a power split propulsion system. This is possible by means of a precise control of the operating conditions of the engine. To operate in the hybrid powertrain efficiently and with low emissions, several energy managements controller strategies are studied. In this work, adaptive Equivalent Minimization Control Strategy (ECMS) and Rule-Based Control (RBC) are used as online controller, and the dynamic programming optimal control is used to size the powertrain. In this sense, the electric machine maximum power, battery energy content, power split device gear ratio as well as the control parameter are studied. Both emissions and fuel consumption are included in the optimization function. The results show that it is possible to reduce the fuel consumption by 17.5% with an energy minimization-oriented strategy. In addition, ECMS is more effective to control both emissions and fuel economy. If a double target is applied, the fuel consumption is reduced to 5% while achieving Euro 6 emissions levels without the need for NOx and particulate matter aftertreatment systems. This strongly reduces the total cost of the propulsion system compared to a conventional vehicle, thus compensating the cost increase due to the hybridization without considering the fuel saving costs.

[EN] Reactivity-controlled compression ignition (RCCI) is a promising energy conversion strategy to increase fuel efficiency and reduce nitrogen oxide (NOx) and soot emissions through improved in-cylinder combustion process. Considering the significant amount of conducted research and development on RCCI concept, the majority of the work has been performed under steady-state conditions. However, most thermal propulsion systems in transportation applications require operation under transient conditions. In the RCCI concept, it is crucial to investigate transient behavior over entire load conditions in order to minimize the engine-out emissions and meet new real driving emissions (RDE) legislation. This would help further close the gap between steady-state and transient operation in order to implement the RCCI concept into mass production. This work provides a comprehensive review of the performance and emissions analyses of the RCCI engines with the consideration of transient effects and vehicular applications. For this purpose, various simulation and experimental studies have been reviewed implementing different control strategies like control-oriented models particularly in dual-mode operating conditions. In addition, the application of the RCCI strategy in hybrid electric vehicle platforms using renewable fuels is also discussed. The discussion of the present review paper provides important insights for future research on the RCCI concept as a commercially viable energy conversion strategy for automotive applications

[EN] The European community foresees a 15% CO2 tailpipe emissions restriction in 2025 and 30% in 2030 for the trucks. While battery electric vehicles would help to reach these levels, their low ranges make them unfeasible for the good transport sector. By this reason, hybrid vehicles are considered the bridge between the current technology and the battery electric vehicles. The 48 V mild hybrid technology is an effective solution due to its low cost and changes needed with respect to the current technology. It also allows the use of electrical components that help to improve the brake thermal efficiency, reduce the emissions and recover energy. This works explores the potential of an electric turbo compound (e-TC) and an electric exhaust gas recirculation pump (e-EGR pump) in a mild hybrid truck platform working under dual-mode dual-fuel (DMDF) combustion with diesel and gasoline. The e-components are simulated by means of 0D-Engine modeling. Finally, a general overview of the potential in real applications is done by means of a vehicle model considering different driving cycles and truck payloads for two truck platforms (18-ton and 25-ton maximum payload). The results show that to achieve the large EGR rates required by the DMDF combustion and meet the air requirements, it necessary the use of both ecomponents together. The evaluation at vehicle conditions allows to conclude that the mild hybrid platform allows to reduce the CO2 emissions around 6% in homologation conditions and 10% in urban cycles. Moreover, it was found that the use of e-components only improves the vehicle efficiency in the cases with low truck payloads.

El presente estudio ofrece un acercamiento al entorno de cultura escrita en el que se desenvolvió la enfermera británica Florence Nightingale durante toda su vida, que mostró una pasión creciente por la escritura. Se comunicó a través de cartas con personas de las más altas esferas de la sociedad victoriana (políticos, intelectuales y científicos), además de mantener una estrecha relación con su familia. Compuso y publicó numerosas obras para el ámbito sanitario y utilizó sistemáticamente el poder omnímodo de la prensa para difundir su obra. Contó con la ayuda inestimable de amigos poderosos e influyentes y en la actualidad su legado escrito se encuentra muy disperso por instituciones de distintos países, siendo en la actualidad una parte de él digitalizado y disponible en internet, con lo que su difusión y estudio permite un mejor conocimiento de la personalidad de la ilustre enfermera británica. Su figura traspasó los límites de la práctica enfermera y circuló por buena parte de Europa la imagen de mujer luchadora e incansable por los derechos de la mujer, apareciendo con frecuencia en la prensa decimonónica de España con rasgos de heroína internacional y modelo a seguir. La escritura en todas sus manifestaciones había jugado un papel determinante en la configuración de la imagen de Florence Nightingale., This study offers an approach to the environment of written culture in which Florence Nightingale developed throughout her life, showing a true passion for writing. She communicated through letters with people from the highest social strata of Victorian society, politicians, intellectuals and scientists, in addition to maintaining a close relationship with her family. She composed and published many works for the health field and systematically used the allencompassing power of the press to spread her work. He had the invaluable help of powerful and influential friends and today his written legacy is widely dispersed by institutions in different countries and is being digitized and hosted on the internet, so its dissemination and study allows a better understanding of the personality of the illustrious British nurse. Her figure went beyond the limits of nursing practice and the image of a woman who fought and tireless for women's rights circulated throughout Europe, frequently appearing in the nineteenth-century press in Spain with traits of an international heroine and role model. Writing in all its manifestations had played a decisive role in shaping Florence Nightingale's image., O presente estudo oferece uma abordagem ao ambiente da cultura escrita em que Florence Nightingale se desenvolveu ao longo de sua vida, demonstrando uma verdadeira paixão pela escrita. Ele se comunicou por meio de cartas com pessoas dos mais altos escalões da sociedade vitoriana, políticos, intelectuais e cientistas, além de manter um relacionamento próximo com sua família. Ele compôs e publicou muitos trabalhos para a área da saúde e usou sistematicamente o poder abrangente da imprensa para divulgar seu trabalho. Contou com a ajuda inestimável de amigos poderosos e influentes e hoje seu legado escrito está amplamente disperso por instituições de diversos países e está sendo digitalizado e hospedado na internet, com a qual sua divulgação e estudo permitem um melhor conhecimento da personalidade de a ilustre enfermeira britânica. Sua figura ultrapassou os limites da prática da enfermagem e a imagem de uma mulher lutadora e incansável pelos direitos da mulher circulou por toda a Europa, aparecendo com frequência na imprensa do século XIX na Espanha com traços de heroína internacional e modelo. A escrita em todas as suas manifestações desempenhou um papel determinante na formação da imagem de Florence Nightingale.

[ES] Los motores de gas para generación de energía están ocupando cada vez mayores cuotas de mercado con respecto a los motores diésel. Con el fin de poder cumplir con las normativas anticontaminantes, la combustión lean ofrece una solución que permite mantener el rendimiento del motor a la vez que se reducen las emisiones contaminantes. Sin embargo, las mezclas muy pobres afectan a la estabilidad de la combustión. En este sentido, el uso de una precámara activa se presenta como una estrategia para mejorar el encendido de la mezcla. El objetivo de este trabajo es analizar la combustión y sus efectos sobre las emisiones contaminantes en un motor de configuración precámara activa empleado para generación, que opera a diferentes cargas, relaciones aire-combustible y tiempos de chispa. Para abordar este objetivo, se llevan a cabo ensayos experimentales en un motor de investigación para tres diámetros de orificio de precámara y se hace uso de una herramienta de modelado 1-D para realizar un análisis termodinámico de las condiciones de la precámara., [EN] Gas engines for power generation are increasing their market shares with respect to diesel engines. To fulfill with emissions regulations, lean combustion offers a solution that allows to maintain engine performance while reducing polluting emissions. However, leaner mixtures affect the combustion stability. In this sense, the use of an active pre-chamber is presented as a strategy to improve the ignition of the mixture. The objective of this work is to analyze the combustion and its effects on polluting emissions in an active pre-chamber configuration engine used for generation, operating at different loads, air-fuel ratios and spark times. To address this objective, experimental tests are carried out on a research engine for a pre-chamber with three different hole diameters and a 1-D modeling tool is used to perform a thermodynamic analysis of prechamber conditions.

[ES] El objetivo general del presente proyecto consiste en determinar las condiciones locales en el interior del cilindro mediante la simulación computacional, ya que experimentalmente no es posible. Se pretende determinar la influencia de los parámetros de control sobre un nuevo modo de combustión basado en una combustión premezclada en la que el encendido de la mezcla aire / combustible se realice mediante el uso de una bujía. A su vez como objetivos específicos se pueden nombrar los siguientes: Crear un modelo de simulación mediante la herramienta computacional StarCD que permite el cálculo de la dinámica de fluidos durante el proceso de mezcla entre el aire y el combustible para las condiciones estudiadas experimentalmente. Mediante los resultados numéricos obtenidos numéricamente de la simulación, determinar la probabilidad de iniciar la combustión de la mezcla estratificada y la probabilidad de que el frente de llama pueda progresar, de acuerdo a la distribución de condiciones locales que dan los resultados tridimensionales. Estudiar la influencia de diferentes variables relativas al proceso de inyección como la presión de inyección, ángulo de cigüeñal en que se inicia la inyección y masa de combustible inyectada, que pueden tener sobre las condiciones termodinámicas y cinemáticas locales que afectan al control que proporciona la actuación de la bujía. Evaluar y analizar los resultados de los ensayos experimentales realizados previamente de forma conjunta con los resultados obtenidos numéricamente para poder explicar la fenomenología del modo de combustión parcialmente premezclado asistido por bujía. Por otra parte, el objetivo académico que tiene la elaboración del presente proyecto es la obtención del título de Ingeniero Aeronáutico, especialidad en Propulsión, en la Escuela Técnica Superior de Ingeniería del Diseño de la Universidad Politécnica de Valencia. Además, como objetivo práctico, se pretende adquirir experiencia y conocimientos de uso de nuev

Nowadays technology has acquired a significant role in our lives; social networking, internet, video games and mobile devices became the primary communication and interaction. Even though this phenomenon may represent a “double edged sword” providing us of positive but also negative results, the internet addiction problem that occurs when people develop a dependence on internet connectivity, might even lead them to have symptoms of anxiety and violence reporting “abstinence periods” when they don´t have access to a network source and generate similar brain alterations that alcohol and drugs does [Phubbing]. Aim. To describe the impact that reflects the technology as a risk factor on interpersonal relations in our environment, as well as locate the possible physiological consequences that these can cause. Method. Sectional survey applied on two groups of 50 students, between 2014-2106. Results. Results throw us that the impact of social media addiction, internet and cell phone´s usefulness represents therefore a significant risk for their health, to hinder emotional relationships within their family and personal impact on cognitive and emotional health. The negative impact is personal and collective, enphasizing the cell phone use while driving a vehicle and its addiction (Phubbing) causes accidents and impacts on morbi-mortality. Conclusions. Phubbing has led to a significant impact in our actual society, increases on morbi-mortality. This is not positive results., Hoy en día la tecnología ha adquirido un papel importante en nuestras vidas; Las redes sociales, Internet, los videojuegos y los dispositivos móviles se convirtieron en la principal comunicación e interacción. Aunque este fenómeno puede representar un "arma de doble filo" que nos proporciona resultados positivos pero también negativos, el problema de la adicción a Internet que ocurre cuando las personas desarrollan una dependencia de la conectividad a Internet, puede incluso llevarlos a tener síntomas de ansiedad y violencia que reportan "abstinencia". periodos” en los que no tienen acceso a una fuente de red y generan alteraciones cerebrales similares a las del alcohol y las drogas [Phubbing]. Objetivo. Describir el impacto que refleja la tecnología como factor de riesgo sobre las relaciones interpersonales en nuestro entorno, así como localizar las posibles consecuencias fisiológicas que estas pueden ocasionar. Método. Encuesta seccional aplicada a dos grupos de 50 alumnos, entre 2014-2106. Resultados. Los resultados nos arrojan que el impacto de la adicción a las redes sociales, internet y la utilidad del teléfono celular representa por tanto un riesgo significativo para su salud, al dificultar las relaciones emocionales dentro de su familia y el impacto personal en la salud cognitiva y emocional. El impacto negativo es personal y colectivo, enfatizando el uso del celular en la conducción de un vehículo y su adicción (Phubbing) provoca accidentes e impactos en la morbimortalidad. Conclusiones. Phubbing ha tenido un impacto significativo en nuestra sociedad actual, incrementos en la morbimortalidad. Esto es resultados no positivos.

Phosphogypsum (PG) is a type of synthetic gypsum generated during the production of phosphoric acid. Each ton of phosphoric acid generates 5 tons of phosphogypsum. This industrial process has caused significant environmental problems worldwide. After an extensive literature review, it was possible to verify that both sedimentary and igneous PG can be used as in materials building components. The use of PG up to 50% meets the limits required for index I, with a radioactivity equivalent to radio-226 and a concentration of radon-222. The data found on bricks (0,11-0,41 Bq m-2 h-1) and plate (0,16-0,41 Bq m-2 h -1) show a lower exhalation rate. It is also found that calcination contributes to the reduction of PG impurities and to the of mechanical strength increase. Mortars and concretes produced with PG-based cementitious systems cementitious systems based on PG achieve high strength (60 MPa, 70 MPa, 80 MPa) and meet the technical feasibility criteria of European standards EN 998-1, EN 998-2, EN 13813, Eurocode 1992 and the American standard ASTM C270. The setting time is influenced by the mineral phase of the PG. It is concluded that cementitious materials produced from phosphogypsum are technically viable and achieve a satisfactory performance. It is possible to advance the following lines: PG-based concrete with high performance, PG-based hydration cement, stabilized mortar, PG-based concrete with high workability and studies about chloride ingress, carbonation, sulfate attack and acid attack in PG-based concrete.

[EN] The use of alternative fuels in compression ignition engines, either completely or partially replacing the conventional ones, have potential to reduce pollutant emissions (especially soot). However, some of these fuels do not provide good ignition features under diesel engine like conditions, which affects engine efficiency. Thus, in order to extend the application of alternative fuels, the current research proposes the use of a laser induced plasma ignition system to assist on the combustion of blends of fuels with less reactivity than pure diesel. This fuel has been chosen as the base component and it has been mixed with gasoline (as the low-reactivity fuel) in different ratios as an example of fuels with very different reactivity properties. Tests have been performed in a single cylinder optically accessible engine, allowing deeper study of combustion development and soot formation. For different in-cylinder conditions and fuel blends, the effect of laser induced plasma ignition system has been evaluated at different crank angle degrees and locations inside the combustion chamber. The application of these blends under low-reactivity engine conditions show that combustion efficiency is dramatically affected. However, the study proves that it is possible to control blend ignition delay and flame lift-off length by means of laser induced plasma. Besides, using the proper ignition system configuration, combustion characteristics similar to those of diesel fuel autoignition can be achieved for high gasoline substitution rates. They lead to similar energy release rates, which confirms that diesel-gasoline blends can reach a combustion efficiency close to pure diesel, while a strong reduction on soot formation was also obtained. These results open a door to efficiency improvement and pollutant reduction by means of a highly tunable ignition of alternative fuel blends.

This is the author's version of a work that was accepted for publication in International Journal of Engine Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published as https://doi.org/10.1177/1468087419865652., [EN] Although there are already several works where the influence of injection parameters on exhaust emissions, and specifically on particulate matter emissions, in diesel engines has been evaluated, the diversity in the results that can be found in the literature indicates the need to carry out new experiments that can provide more information about the influence of these parameters on modern diesel engines. This study intends to be placed within this scientific framework, hence a parametric study was carried out based on the independent modification of the main injection timing and the injection pressure with respect to the nominal conditions of a new Euro VI direct injection diesel engine. Four steady-state operation points of the engine map were chosen: 25% load and 950 r/min, 50% load and 1500 r/min, 75% load and 2000 r/min and 100% load and 2200 r/min, where in each of these operation points, the variations of the injection parameters in the study on the combustion process and its consequent impact on the particle size distribution, including an analysis of the geometric mean diameter values, were evaluated. The results showed that the different injection strategies adopted, despite not significantly affecting the engine efficiency, did cause a significant impact on particle number emissions. At the low load operation, the size distribution showed a bimodal structure, and as the main injection timing was delayed and the injection pressure was decreased, the nucleation-mode particle concentration decreased, while the accumulation-mode particle concentration increased. In addition, at medium load, the nucleation-mode particle emission decreased considerably while the accumulation-mode particle emission increased, and this increase was much greater with the main injection timing delay and the injection pressure reduction. Similar behavior was observed at high load, but with a much more prominent pattern.

[ES] En los últimos años ha aumentado la preocupación por el cambio climático. El uso de combustibles fósiles está provocando un aumento en la temperatura promedio global del planeta. Una alternativa adecuada a estos combustibles fósiles es el hidrógeno, sin embargo, la alta inflamabilidad y una llama invisible son inconvenientes importantes para generalizar el hidrógeno como combustible. Estos problemas han llevado a sugerir que el amoníaco es un posible combustible e hidrógeno, pero también presenta inconvenientes como bajas velocidades de llama, entre otros. Una opción interesante es mezclar amoníaco con hidrógeno como promotor de la combustión para mejorar las características deseables del amoníaco, pero al mismo tiempo, mantener su característica libre de carbono. Además, con el uso de quemadores porosos podemos lograr una mejor estabilización de las llamas premezcladas porque los medios porosos mejoran el calor, el impulso y la transferencia de masa, lo que aumenta la velocidad de combustión. Sin embargo, no todas las llamas se pueden propagar dentro de un medio poroso, para lograr esta propagación de la llama dentro de la matriz porosa se deben cumplir algunas condiciones. Por lo tanto, en la siguiente investigación se realizará un estudio teórico para predecir qué mezclas de hidrógeno y amoníaco pueden propagarse llamas dentro de diferentes matrices porosas. Más tarde, estos casos se probarán en el laboratorio para verificar estas predicciones., [EN] In the past few years there have been growing more and more concerns over the climate change. The use of fossil fuels is triggering a raise in the global average temperature of the planet. One suitable alternative to these fossil fuels is hydrogen. However, high flammability and an invisible flame are important drawbacks to generalize hydrogen as a fuel. These problems have led to suggest ammonia as a potential fuel and hydrogen carrier, but also ammonia presents drawbacks as low flame speeds, among others. One interesting option is mix ammonia with hydrogen as a combustion promoter in order to enhance the desirable characteristics of ammonia, but at the same time, keeping its carbon-free characteristic. Besides, with the use of porous burners, a better stabilization of the premixed flames can be achieved, because porous media enhance the heat, momentum, and mass transfer leading to an increasing the burning speed. However, not all flames can be propagate inside a porous media, to achieve this flame propagation inside the porous matrix some conditions have to be met. So, in the following research a theoretical study will be done in order to predict which hydrogen-ammonia mixtures flames can propagate inside different porous matrices. Later these cases will be tried in the laboratory to verify these predictions.

[ES] Simular el comportamiento del Spray A de acuerdo a la ECN (Engine Combustion Network), haciendo uso de la herramienta OpenFOAM. Realizar la configuración experimental completa,con el fin de estudiar la capacidad de OpenFOAM para resolver el problema mediante RANS. Comparar los resultados obtenidos con los datos experimentales de la ECN. Discutir la fiabilidad de los resultados., [EN] Spray A is a spray composed mainly of dodecane and which has been widely studied by several research groups and universities. Spray A was defined not only as a fuel but also as a set of conditions and parameters that define the initial conditions and boundary conditions. In this way, anyone who studies Spray A can compare the results with anyone who has studied it before. The aim of this project is to assess the capability of OpenFOAM, a open-source CFD software, to solve the problem of Spray A injection in a combustion chamber. In this way, thanks to the extensive experimental database available, it will be possible to compare the results of the simulations with the experimental data. This project will be based on the study of non-reactive and reactive cases. The first is, without combustion, considering an inert environment, the second, the combustion is attained, introducing an oxidant into the hot environment. For the study of these cases, the liquid penetration of the fuel, the vapor penetration and the radial concentration of the fuel will be compared to the experimental results. Finally, a study will also be made on the sensitivity of the computational costs of the different simulations according to the different parameters that characterise them.

[ES] Este trabajo consiste en el estudio de diversas posibilidades compositivas de un Álbum ilustrado utilizando los recursos estudiados (ilustración vectorial, tipografía, edición en mapa de bits), además de investigar, desarrollar y aplicar otros nuevos por el camino. Utilizaremos momentos destacados en la historia de los deportes electrónicos en League of Legends con motivo de los 10 años del competitivo de este videojuego, consiguiendo así con la ayuda de la unión código escrito, [EN] This work consists in the study of diverse compositional possibilities of an Illustrated Album using the studied resources (vector illustration, typography, bitmap edition), as well as researching, developing and applying new ones along the way. We will use highlights in the history of electronic sports in League of Legends on the occasion of the 10 years of the competitive of this videogame, thus achieving with the help of the union of written and visual code, a representation of the history and sensations of this exciting competition.

[EN] Previous works demonstrated that the use of Oxymethylene ether (OMEx) in advanced combustion modes, as the dual-mode dual-fuel combustion, leads to a notable reduction of the lifecycle CO2 emissions while promoting lower NOx and soot emissions than those from conventional diesel combustion. Nonetheless, the low heating value of OMEx results in a fuel consumption increase. A possible solution to avoid this drawback is by blending OMEx with diesel fuel. This will help to introduce the OMEx in the market with minimum changes in the infrastructure. In this context, this work evaluates the impact of using OMEx-diesel blends in different mass percentages (50% and 70% of OMEx in diesel), compared to the reference net fuels (net diesel and OMEx) in a multi-cylinder compression ignition engine operating under dual-mode dual-fuel combustion at different engine loads (25%, 50%, 80% and 100%) and 1800 rpm. At each condition, an air mass sweep was performed to assess the limiting operating conditions with each fuel due to either excessive pressure gradients and soot production, or low combustion efficiency. The results suggested that the OMEx-diesel blends allow to reduce the soot emissions compared to net diesel for all the conditions tested. In addition, blends having an OMEx mass content greater than 70% allowed to fulfill the EUVI limits for NOx with ultra-low soot levels (< 0.01 g/kWh) up to 80% engine load. Nonetheless, the unique fuel able to achieve the EUVI limit for NOx with zero soot emissions simultaneously at 100% of engine load was found to be the pure OMEx.

[EN] Dual-mode dual-fuel (DMDF) combustion stands over other low temperature combustion strategies as it is able to operate over the entire engine map by transitioning between reactivity controlled compression ignition and diffusive combustion depending on the engine load. In combination with non-sooting e-fuels, it is able to achieve low NOx and soot levels even at high loads. Oxygenated fuels like poly-oxymethylene dimethyl ethers (OMEx) have been already proved to present an outstanding NOx-Soot trade-off improvement when used in combination with a DMDF combustion strategy. One drawback of OMEx is that, despite having a high reactivity, it has a low lower heating value, which requires considerably longer injection events compared to other traditional fuels in order to achieve the same engine power output. The long injections limit the flexibility of the injection strategy and result in extremely long combustion durations. A possible solution to this problem resides in moving towards injectors with higher flow rate capacities, but this may compromise the mixing and combustion processes. This work aims to shed some light on the implications of changing the engine hardware to overcome this limitation by testing a DMDF mull-cylinder engine using gasoline as the low-reactivity fuel and diesel or OMEx as the high reactivity fuels with injectors of different flow capacity. The results show that a concise analysis of the involved phenomenology of the combustion process allows to find out the trade-off between the engine-out emissions and the mixing capacity of the injection system while the engine performance is not significantly affected.

[EN] The European commission is targeting a 15% reduction in CO2 emissions for medium and heavy-duty transportation starting in 2025. Moreover, the next European normative (EU VII) will impose a decrease of 50% for NOx and particulate matter emissions with respect to the current EUVI normative. Meeting these requirements pose a significant challenge to truck and bus manufacturers. Several proposals appeared in the last few years as improve the cabin aerodynamics, decrease the friction losses and improve the powertrain efficiency. The last point involves improving the current combustion systems as well as the transmission and energy management. This work proposes to couple two potential technologies to reduce at the same time the global (CO2) and local pollution (NOx and soot). For this, two truck platforms representative of medium-duty applications (18 ton and 25 ton) are tested using the reactivity controlled compression ignition (RCCI) combustion mode with diesel and gasoline as fuels. In addition, the trucks are electrified to full hybrid technology in a parallel pre-transmission (P2) architecture. A 0D vehicle numerical model is used to evaluate the trucks under four different driving cycles representative of homologation and real driving conditions. The numerical model is validated against on road measurements. The RCCI combustion is modeled by means of a map-based approach with 54 points measured in steady-state conditions. This work presents a complete engine map calibration with measurements up to 350 hp using two combustion modes inside the map (so-called dual-mode dual-fuel). As a baseline, the commercial diesel no-hybrid trucks and the dual-fuel no-hybrid trucks are used. The results show the potential of the dual-mode dual-fuel combustion to achieve ultra-low NOx and soot emissions. In addition, the CO2 target reduction is achieved for several truck platforms and driving conditions due to the hybridization of the driveline. The cycles with large phases o

[EN] The diesel/gasoline dual-mode dual-fuel (DMDF) combustion concept was optimized in a compression-ignition engine by combining the computational fluid dynamics (CFD) simulations with the genetic algorithm. Seven operating parameters with remarkable influences on the engine performance were chosen as the variables to be optimized for simultaneously minimizing the fuel efficiency, nitrogen oxides (NOx), and soot emissions. Moreover, the potential of the further improvement of the DMDF combustion concept was discussed, and the rationality of this strategy was demonstrated. The results indicate that, at low load, simultaneous improvement of the fuel economy and emissions can be realized by strengthening the homogeneous combustion. At mid load, the fuel economy can be improved by reducing the heat transfer losses, while the NOx emissions are sacrificed to some extent. At high load, improved fuel economy can be realized by transferring a part of diffusion combustion to premixed reactivity-controlled compression ignition (RCCI) combustion. Concerning the operating parameters, lower intake temperature is beneficial to decrease the transfer losses, and the control of intake temperature is crucial for the stable operation of DMDF combustion under wide load conditions. Overall, gross indicated thermal efficiency above 45% is achieved, and the NOx and soot emission can be maintained under the Euro 6 standard for the test load range.

[EN] With the aim of reducing pollutant emissions from internal combustion engines (ICE), the application of stoichiometrically operated spark ignition (SI) engines, for light-duty vehicles, has been overcoming the compression ignition (CI) engines market share throughout the past years. The ability of a substantial reduction of the primary harmful emissions (HC, CO, and NOx) through the use of the simple three-way catalyst (TWC) is the main reason for that. Nonetheless, with increasing attention to CO2 emissions, the development of highly efficient downsized SI engines turn to be of enormous interest. The synergies of multiple systems such as direct injection, turbocharger, and variable valve actuation are able to lead the SI efficiencies closer to those of CI engines. However, to enable high load operation on such downsized engines, the compression ratio (CR) must be reduced due to knock limitations, reducing the partial-load operations efficiency. The implementation of two-stage variable compression ratio (VCR) systems enables the extraction of high thermal efficiency with high CR at lower loads and extended knock-free high load operation with low CR. In this study, the evaluation of a two-stage VCR system applied to a state-of-the-art downsized SI engine was made through standard driving cycle simulations. The VCR mechanism is composed of an eccentric element in the small end of the connecting rod, which is rotated to increase/decrease the effective connecting rod length, achieving the CRs of 12.11:1 and 9.56:1. The engine was run in an eddy-current dynamometer test bench throughout the essential operating range to obtain the brake specific fuel consumption (BSFC) map. The VCR mechanism CR switching delay was also experimentally characterized to derive a function of the operating conditions. The measured map was entered into the map-based driving cycle simulation with a sub-model to account for the isolated effects of the transient period encompassing the compre

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Energy & Fuels, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.energyfuels.0c00091., [EN] Recent research has demonstrated that a reduction in pollutant emissions of diesel engines can be achieved by using high octane fuels such as gasoline, methane, or liquefied petroleum gas. Therefore, in this study, the focus was to investigate the influence of blends of diesel and gasoline on combustion characteristics such as ignition delay, rate of heat release, and lift-off length as well as the influence on soot formation. The experiments were carried out in a test rig with optical access which mimics a single-cylinder diesel engine. Four blends were tested: one blend with 100% diesel and then three diesel-gasoline blends with 30%, 50%, and70% gasoline. The blends were made in volumetric proportions and injected using a common rail injection system without any kind of modification. The ignition delay and the apparent heat release were obtained by means of the in-cylinder pressure signal. Furthermore, the combustion development and soot formation were studied using three optical techniques: OH* chemiluminescence, natural luminosity, and diffused back-illumination extinction imaging (DBI). Different engine operating conditions were analyzed. Results showed that ID increases with the gasoline content in the blend. Similarly, as the reacting time increased, the lift-off length was longer. On the other hand, the apparent rate of heat release decreased due to a reduction of the fuel injection rate, which depends on the density of the blend. In addition, differences in the flame radiation were also observed. Gasoline-diesel blends had less luminosity, which is related to less soot formation. To confirm this, the KL factor obtained from the DBI technique was determined, and it was concluded that increasing the gasoline fraction in the blend reduces soot formation.

[EN] The fundamental behaviour on ignition and combustion characteristics of blends of Hydrotreated Vegetable Oil and Liquid Petroleum Gas was investigated in a constant high pressure, high temperature combustion chamber, using a prototype lab-scale injection system adapted from a conventional common-rail system to conduct the injection events, ensuring that fuel was liquid at any point of the injection system and avoiding the formation of fuel vapour bubbles that could alter the injected fuel behaviour. The ignition delay, flame lift-off length and the soot formation were studied by means of high-speed imaging techniques, for different operating conditions. The aim of the work is to characterize the effect of Hydrotreated Vegetable Oil-Liquid Petroleum Gas blend ratios on the previously mentioned parameters. Experimental results show that the behaviour of the fuel blends follow the expected trends of conventional diesel type fuels when varying ambient temperature, density and injection pressure. Hydrotreated Vegetable Oil, being the highest reactivity fraction, controls auto ignition of the blend. However, Liquid Petroleum Gas acts as combustion inhibitor increasing both ignition delay and lift-off length as its ratio in the blend increases. As a consequence, the differences observed in terms of flame radiation suggest that increasing Liquid Petroleum Gas fraction reduces soot formation as it promotes a higher air/mixture.

[EN] Hybrid Electric Vehicles (HEVs) can be considered as a potential technology to promote the change from conventional mobility to e-mobility. However, the real benefits in terms of CO2 emissions depend on a great extent on their mode of use, vehicle design and electricity source. On the other hand, in the last few years, advanced combustion modes as Reactivity Controlled Compression Ignition (RCCI) showed great advantages in terms of NOx and soot emissions reduction. This paper has the purpose of assessing, through numerical simulations fed with experimental results, the potential of different hybrid vehicles when used together with a low temperature combustion mode. In particular, the dual-fuel Mild (MHEV), Full (FHEV) and Plug-in (PHEV) hybrid electric vehicles are tested and compared to the original equipment manufacturer (OEM) and the conventional dual-fuel powertrain, both no-Hybrid vehicles. The powertrains are optimized to meet the current European homologation legislation Worldwide Harmonized Light Vehicle Test Procedure (WLTP). After that, a deep analysis is performed in terms of performance and emissions. Lastly, a life-cycle analysis (LCA) is performed to evaluate the real potential of the different technologies. The results show that the PHEV has the highest benefits in terms of fuel consumption and engine-out emissions. With this technology, it is possible to achieve the 50 g/km CO2 target for the PHEVs with a medium battery size (15 kWh), while NOx and soot levels are under the Euro 6 limits. In addition, the RCCI technology shows great benefits to achieve the Euro 6 soot level for the other hybrid platforms. The LCA shows that the PHEVs can achieve 12% reduction of the total CO2 with respect to the FHEVs, and 30% with respect to the no-hybrid diesel platform.

[EN] Reactivity Controlled Compression Ignition combustion technology potentials are well known for the capability to drastically reduce the engine-out nitrogen oxides and soot emissions simultaneously. Its implementation in mid-term low-duty diesel engines can be beneficial to meet the upcoming regulations. To explore the potential of this solution, experimental data are used from a compression ignition 1.9 L engine, which is operated under two combustion-modes: Reactivity Controlled Compression Ignition and conventional diesel combustion. Meanwhile, also the carbon dioxide emissions limitations must be fulfilled. To achieve this goal, the benefits associated to powertrain electrification in terms of fuel economy, can be joined with the benefits of RCCI combustion. To do so, two different supervisory control strategies are compared: Adaptive Equivalent Minimization Control Strategy and Rule-Based Control strategy, while dynamic programming is used to size the electric grid of the powertrain to provide the best optimal solution in terms of fuel economy and emissions abatement. The analysis of the designed hybrid powertrain is carried out numerically with GT-Suite and Matlab-Simulink software. The results show a great potential of the parallel full-hybrid electric vehicle powertrain equipped with the dual-mode engine to reduce the engine-out emissions, also to increase fuel economy with respect to the homologation fuel consumption of the baseline vehicle. The optimal supervisory control strategy was found to be the emissions-oriented Adaptive Equivalent Minimization Control Strategy, which scores a simultaneous reduction of 12% in fuel consumption, 75% in engine-out nitrogen oxides emissions and 82% in engine-out soot, with respect to the baseline conventional diesel combustion engine vehicle.

[EN] The dual-mode dual-fuel (DMDF) strategy has been demonstrated to be a potential combustion mode to cover all the engine map with low-to-moderate NOx and soot emissions and high efficiency simultaneously. This can be accomplished by modifying the injection strategy to promote a fully premixed or a dual-fuel diffusive combustion depending on the operating conditions. The main limitation of the DMDF are the high concentrations of unburned hydrocarbons and carbon monoxide coupled with low exhaust temperatures, which can be a challenge for the stock diesel oxidation catalyst (DOC). Moreover, the use of a diffusive combustion combined with high EGR rates to avoid mechanical issues at high load enhances the soot formation, which can compromise the final soot levels in a homologation cycle. To evaluate these aspects, this work studies the performance and emissions of a DMDF truck concept along a WHVC and different in-service conformity cycles through vehicle systems simulations. For both types of cycles, five payloads were tested (0%, 25%, 50%, 75% and 100%) to evaluate the impact of this parameter on the operating points distribution inside the DMDF map. The first results show that the DMDF concept provides engine-out NOx levels below the EUVI regulation at normative payload (50%) with similar fuel consumption than the conventional diesel truck. On the other hand, the engine-out HC and CO emissions exceed their respective limits in all the cases, while the engine-out soot emissions only reach the EUVI levels up to 25% payload. By this reason, the stock DOC and diesel particulate filter from the conventional diesel truck were modelled and fitted to the DMDF truck model. The results evidenced that the use of these two ATS allows to achieve the EUVI limits in terms of tailpipe HC, CO and soot independently on the cycle and payload analyzed. Moreover, considering the tailpipe emissions values achieved with ATS at 50% payload, it can be inferred that both devices could be

[EN] Synthetic fuels (E-fuels) have shown to be an interesting alternative to replace the fossil diesel fuel due to its CO2 reduction potential as well as for their capability to diminish the soot production and therefore for improving the soot-NOX trade-off in Compression Ignition engines. Thus, the main objective of this paper was to better understand the combustion process and the in-cylinder soot formation of two of the most popular E-fuels currently: Fischer-Tropsch (FT) diesel and Oxymethylene dimethyl ether (OMEX). To achieve this aim, a single cylinder optical CI engine with a commercial piston geometry was used. Thee optical techniques (Natural Luminosity-NL, OH* chemiluminescence and 2-color pyrometry) were applied to analyze the combustion evolution and quantify the soot formation at different loads (1.5, 4.5 and 7.5 bar IMEP). OMEX presented the largest injection duration due to the low LHV. For the NL analysis, OMEX showed the lowest light intensity for the three loads tested, indicating a very low soot production. Despite of the low NL intensity, it presented the highest OH* chemiluminescence signal, indicating a higher presence of near-stoichiometric zones due to the high amount of oxygen. Regarding FT diesel, it showed a combustion behavior similar to the commercial diesel. NL, OH* and 2-color technique analysis indicated that for the three conditions tested, FT diesel presented lower soot production and a faster soot oxidation than commercial diesel.