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[ES] Se espera que la nueva generación de motores de encendido provocado represente la mayor parte del mercado en el contexto de la propulsión de vehículos con o sin hibridación. Sin embargo, la tecnología actual todavía tiene desafíos críticos por delante para cumplir con los nuevos estándares de emisiones de CO2 y contaminantes. Consecuentemente están surgiendo nuevas tecnologías para mejorar la eficiencia de los motores y que estos cumplan con las nuevas normativas anti-contaminación. Entre otras, una de las tendencias más seguidas en la actualidad es la reducción de tamaño de los motores, concepto conocido como "downsizing", bajo la técnica de la turbosobrealimentación. Las nuevas tecnologías de turbocompresores, como las turbinas de geometría variable (TGV), se empiezan a considerar para su aplicación en las exigentes condiciones de funcionamiento de los nuevos motores de encendido provocado. En este trabajo, a partir de datos experimentales obtenidos en la sala de ensayos del motor, se propone una metodología de calibración del modelo completo de motor 1-D: se realiza un análisis teórico dirigido a asegurar el control total sobre cualquier aspecto de la simulación. En otras palabras, el modelo de motor 1-D se ajustó completamente con respecto a los datos experimentales del motor. Además, se demuestra la necesidad del postprocesamiento y validación de datos experimentales relacionados con mapas de turbocompresores, ya que se requiere desacoplar fenómenos como la transferencia de calor y las pérdidas por fricción de los denominados mapas experimentales de turbocompresores. De acuerdo con esto, se presenta una metodología para la obtención de mapas de turbocompresores, basada en una campaña experimental dividida en varias tipologias de ensayos y seguida de la etapa de modelado. La etapa de modelado se lleva a cabo utilizando modelos de turbocompresores integrales ya desarrollados o disponibles en la literatura. Adicionalmente se aborda la mejora en la precisión d, [CA] S'espera que la nova generació de motors d'encesa per espurna representi la major part del mercat en el context de la propulsió de vehicles amb o sense hibridació. No obstant això, la tecnologia actual encara té reptes crítics per davant per complir amb els nous estàndards d'emissions de CO2 i contaminants. Conseqüentment estan sorgint noves tecnologies per millorar l'eficiència dels motors i que aquests compleixin amb les noves normatives anti-contaminació. Entre d'altres, una de les tendències més seguides en l'actualitat és la reducció de grandària dels motors, concepte conegut com "downsizing", sota la tècnica de la turbosobrealimentación. Les noves tecnologies de turbocompressors, com les VGT, es comencen a considerar per la seva aplicació en les exigents condicions de funcionament dels nous motors d'encesa per espurna. En aquest treball, a partir de dades experimentals obtingudes a la sala d'assajos de l'motor, es proposa una metodologia de calibratge del model complet de motor 1-D: es realitza una anàlisi teòrica dirigit a assegurar el control total sobre qualsevol aspecte de la simulació. En altres paraules, el model de motor 1-D es va ajustar completament respecte a les dades experimentals del motor. A més, es demostra la necessitat del posprocesamiento i validació de dades experimentals relacionats amb mapes de turbocompressors, ja que es requereix desacoblar fenòmens com la transferència de calor i les pèrdues per fricció dels denominats mapes experimentals de turbocompressors. D'acord amb això, es presenta una metodologia per a l'obtenció de mapes de turbocompressors, basada en una campanya experimental dividida en diverses tipologies d'assajos i seguida de l'etapa de modelatge. L'etapa de modelatge es porta a terme utilitzant models de turbocompressors integrals ja desenvolupats disponibles a la literatura. A més a s'aborda la millora en la precisió de les simulacions quan es comparen mapes de turbocompressors postprocessats amb mapes purament expe, [EN] The new generation of spark ignition (SI) engines is expected to represent most of the future market share in the context of power-train with or without hybridization. Nevertheless, the current technology has still critical challenges in front to meet incoming CO2 and pollutant emissions standards. Consequently, new technologies are emerging to improve engine efficiency and meet new pollutant regulations. Among others, one of the most followed trends is engine size reduction, known as downsizing, based on the turbocharging technique. New turbocharger technologies, such as variable geometry turbines (VGT), are evaluated for their application under the demanding operating conditions of SI engines. In this work, from experimental data obtained in an engine test cell, a 1-D complete engine model calibration methodology was conducted: a theoretical analysis aimed at ensuring full control on any aspect of the simulation. In other words, the 1-D engine model was fully fitted with respect to the experimental engine data. Furthermore, it is evidenced the requirement of post-processing and validating the experimental data dealing with turbocharger maps, since phenomena such as heat transfer and friction losses are required to be decoupled from the so-called experimental turbocharger maps. Accordingly, a methodology for turbocharger maps obtention is presented, based on an experimental campaign divided into several test typologies and followed by the modelling stage. The modelling stage is carried out making usage of already developed integral turbocharger models available in the literature. Additionally, the improvement in the accuracy of the simulations when post-processed turbocharger maps are compared against purely experimental maps is addressed. Taking advantage of the highly validated and physically representative 1-D gas-dynamics engine model and turbocharger validated maps, it is discussed how experimental uncertainties or "out-of-control" variables may impact th

[ES] Se ha diseñado el sistema de sobrealimentación de un innovador motor de pistones opuestos de dos tiempos. El diseño se ha centrado en la optimización del consumo específico y de la potencia específica para a un sistema de propulsión híbrido serie. Los principales retos del proyecto han sido dimensionar correctamente la turbomáquinaria, elegir la tipología de la turbina y sintonizar el colector de escape para mantener el mínimo barrido necesario en las condiciones operativas del motor. La reducción de la potencia consumida por una bomba de barrido adicional ha sido una de las mayores dificultades para cumplir los objetivos del proyecto., [EN] It has been designed the turbocharging system of an innovative two stroke opposed pistons engine. The design has been focused in optimizing bsfc and maximizing specific power facing a range exender application for a series hybrid powertrain. The main challenges of the project has been sizing correctly the turbomachinery, chosing the tipology of the turbine and tunning the exhaust manifold to keep minimun needed scavenging in the engine operative conditions. The reduction fo the power consumed by an additional scavenge pump has been one of the major difficulties to fulfill project objectives.

[EN] In this work, a methodology is proposed to standardize turbochargers testing based on measuring the maps twice: in close to adiabatic and in diathermal conditions. Along the paper, it is discussed with special detail the impact of the procedure followed to achieve said quasi-adiabatic conditions in both the energy balance of the turbocharger and the testing complexity. As a conclusion, the paper proposes a methodology which combines quasi-adiabatic tests (cold and hot gas flow) with diathermal tests (hot gas flow) in order to extract from a turbocharger gas-stand all information needed by engine designers interested in controlling or one-dimensional-modeling the internal combustion engine (ICE). The methodology is completed with a guide for calibrating said control-oriented turbocharger models in order to separate aerodynamic efficiency (adiabatic) from heat transfer (HT) losses and from friction losses in the analysis of the turbocharger performance. The outsourced calibration of the turbocharger model allows avoiding uncertainties in the global ICE model calibration, what is very interesting for turbochargers benchmarking at early ICE-turbo matching stages or for global system analysis at early control design stages.

[EN] New generation of spark ignition (SI) engines are expected to represent most of the future market share in a context of powertrain hybridization. Nevertheless, the current technology has still critical challenges in front to meet incoming CO2 and pollutant emissions standards, so new technologies are emerging to improve engine efficiency. In parallel to combustion concepts, a key required trend is downsizing based on high engine boosting. New turbocharger technologies, such as variable geometry turbines (VGT), become suitable for its application under the demanding operating conditions of SI engines. In this work, a methodology for the analysis of the VGT usage in comparison with traditional waste-gate (WG) turbine is presented. From experimental data obtained in engine test cell, a theoretical analysis aimed at ensuring full control on turbine boundary conditions, such as combustion variability, compressor map or engine calibration, was conducted. Taking advantage of highly validated and physically representative 1-D gas-dynamics and turbocharger models, the engine performance is discussed as a function of the turbine technology at full and partial load in a wide range of engine speed at the same time as the altitude impact is addressed. In all, it was found that VGT technology shows less limitations in extreme working conditions, such as low- and high-end torque regions, where the WG technology represents a limitation in terms of the maximum power output. Full load differences become more even more evident in altitude working conditions. When it comes to partial loads, differences in fuel consumption are minor, but potentially beneficial for VGTs.

[EN] As pollutants and fuel consumption requirements become more constraining, new internal combustion engines generation arise to fulfill future automobile market regulations. In these context spark ignition (SI) engines working under hybridized structures are expected to represent one of the most viable and feasible technical approaches. In parallel to the already implemented 4-stroke turbocharged engines, new engine concepts are being conceived from their birth to meet nowadays standards. This work shows a new engine concept assessed to fit series hybrid configurations from the earliest design stages, and to fulfil requirements of the named "zero-emissions" urban areas. In this research work, a new opposed piston 2-stroke engine architecture based on rodless innovative kinematics is described. The potential of this engine is based on its compactness, absence of vibrations and simplicity, going in hand with very competitive figures in terms of power density and fuel consumption. The engine unit has been designed, assembled, and tested to analyze several performance aspects, such as gas exchange and combustion. Taking advantage of the experimental campaign, a one-dimensional (1D) gas-dynamics engine model was developed and validated. Finally, the engine model was used for analyzing several potential upgrades and results have been discussed in detail. The target has always been to improve fuel consumption figures, below the best standards in market available internal combustion engines, while keeping engine concept simplicity and building costs.

The aerospace sector is one of the main economic drivers that strengthens our present, constitutes our future and is a source of competitiveness and innovation with great technological development capacity. In particular, the objective of manufacturers on assembly lines is to automate the entire process by using digital technologies as part of the transition toward Industry 4.0. In advanced manufacturing processes, artificial vision systems are interesting because their performance influences the liability and productivity of manufacturing processes. Therefore, developing and validating accurate, reliable and flexible vision systems in uncontrolled industrial environments is a critical issue. This research deals with the detection and classification of fasteners in a real, uncontrolled environment for an aeronautical manufacturing process, using machine learning techniques based on convolutional neural networks. Our system achieves 98.3% accuracy in a processing time of 0.8 ms per image. The results reveal that the machine learning paradigm based on a neural network in an industrial environment is capable of accurately and reliably estimating mechanical parameters to improve the performance and flexibility of advanced manufacturing processing of large parts with structural responsibility.

[ES] El objetivo principal de este TFG es el modelado de una máquina de ensayos a fatiga, para poder calibrar esta máquina. Esta calibración consiste en obtener la relación entre las tensiones que aparecen en la probeta y las tensiones que podemos medir en la máquina.

[ES] Los vehículos diésel de automoción están sufriendo en los últimos tiempos un ataque y discriminación a diferentes niveles ante una tecnología competitiva (vehículos eléctricos) que igualmente está recibiendo demasiada atención mediática y encumbramiento sin un claro soporte científico en ninguna de las dos caras. Aquí se ha presentado una comparativa objetiva de pros y contra en ambos casos, en base a recientes estudios así como a datos objetivos que hay que tener en cuenta de cara a un claro análisis objetivo.

[ES] Los motores de combustión interna alternativos (MCIA) son el principal sistema de propulsión en el transporte por carretera. El presente trabajo presenta un análisis objetivo de la imposibilidad directa del reemplazo total de los mismos como planta motriz en los vehículos. A día de hoy, este comentario es absolutamente cierto incluso considerando el mejor escenario de previsión de crecimiento para los vehículos eléctricos e híbridos. Los argumentos para defender esta postura tienen en cuenta el crecimiento en la demanda de transporte, el avanzado desarrollo de motores ultra limpios y de alta eficiencia, la disponibilidad de combustibles de origen fósil, los bajos tiempos de repostaje y alta densidad energética de los combustibles líquidos. Todos ellos son fuertes argumentos para apoyar una viabilidad a medio y largo plazo de los MCIA como planta propulsora predominante en las aplicaciones del transporte por carretera., [EN] Internal combustion engines (ICE) are the main propulsion systems in road transport. This work discusses the impossibility of replacing them as a power plant in most vehicles. Nowadays, this statement fulfils even considering the best growth scenario for all-electric and hybrid vehicles. The arguments supporting this position took into account the growing demand for transport, the strong development of ultra clean and more efficient ICE, the availability of fossil fuels, the low refuelling times and the high energy density of liquid fuels. Overall, there seemed to be strong arguments to support the medium-long-term viability of the ICEs as the predominant power plant for road transport applications.

[ES] Los motores de combustión turbosobrealimentados son los principales propulsores de los vehículos actuales. Continuar estudiando el acoplamiento entre el turbogrupo y el motor alternativo es fundamental para mejorar su eficiencia y reducir las emisiones contaminates de los mismos. En este TFM se analiza la importancia de usar modelos integrales (holísticos) del turbogrupo. Por modelo integral se entiende aquel que aborda tres aspectos: Eficiencia aerodinámica de las turbomáquinas, pérdidas mecánicas del eje del turbogrupo y fenómenos de transmisión de calor en el turbogrupo. En la actualidad no existen modelos comerciales que aborden los tres aspectos de manera combinada, lo que dificulta enormemente el modelado numérico con precisión de los motores turbo-sobrealimentados. En el TFM se analiza las ventajas de usar este tipo de modelos frente a la práctica standard con el foco en la buena predicción de la contrapresión de escape del motor y la temperatura del aire y los gases de escape a la salida de las turbomáquinas. Este análisis se hace para un motor Diesel con EGR de baja presión y tanto para funcionamiento estacionario como transitorio. Una parte importante del trabajo ha consistido en proponer un protocolo de calibración de los modelos 1D para este tipo de motores. Además se proponen nuevos submodelos para abordar los procesos de transmisión de calor en turbogrupos con características innovadoras como son los compresores con voluta refrigerada y los e-chargers (turbocompresores eléctricos)., [EN] Turbocharged combustion engines are the main engines of current vehicles. Continuing to study the coupling between the turbogroup and the alternative engine is fundamental to improve its efficiency and reduce pollutant emissions from them. In this TFM the importance of using integral (holistic) models of the turbogroup is analyzed. Integral model refers to one that addresses three aspects: aerodynamic efficiency of turbomachinery, mechanical losses of the turbogroup axis and heat transfer phenomena in the turbogroup. At present there are no commercial models that address all three aspects in a combined manner, which makes it extremely difficult to numerically model the turbo-supercharged engines with precision. In the TFM, the advantages of using this type of models in comparison with the standard practice are analyzed with the focus on the good prediction of the exhaust back pressure of the engine and the temperature of the air and the exhaust gases at the exit of the turbomachines. This analysis is made for a diesel engine with low pressure EGR and for both stationary and transient operation. An important part of the work has been to propose a calibration protocol for the 1D models for this type of engine. In addition, new submodels are proposed to address heat transfer processes in turbogroups with innovative features such as compressors with refrigerated volute and e-chargers (electric turbochargers)