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Given that today’s real-world diesel fuel supply is comprised of biodiesel as a blendstock with petrodiesel, understanding how addition of biodiesel affects exhaust particle properties and their subsequent effect on human health is critically important. Here, samples of a commercial waste vegetable oil biodiesel B100 fuel were subject to thermal oxidation at 110oC for 5, 10 or 20 hr before diesel engine dynamometer emissions testing as the neat fuel (B100) and as a 20% v/v biodiesel blend (B20) with petrodiesel. Exhaust particulate matter samples collected using impingers were tested for the ability of the particles to initiateformation of reactive oxygen species (ROS) using the abiotic dithiothreitol (DTT) assay. DTT Activity [nmol DTT consumed per minute per mg PM] of three B20, three B100 as well as petrodiesel (B0) fuels over a total of 13 emissions tests with a light-duty diesel engine were compared. Combining data for emissions tests by fuel blend and oxidation status, mean DTT Activity was similar between B0 and B20 (10hr oxidized), B100 (neat) and B100 (5 hr). Particles from the B20 neat and B20 (20 hr) fuels had the highest measured DTT Activity whereas the B100 neat and B100 (5 hr) had the lowest DTT Activity. Twenty hours of thermal oxidation conditions resulted in the highest measured DTT Activity (or highest potential to form ROS) for both B20 and B100 fuels and IP=0. An inverse relationship between storage stability (opposite of degree of fuel oxidation) of the biodiesel fuel as measured by induction potential (IP) and the ROS formation potential: higher DTT Activity was noted for the B100 fuels with the lowest IP. Results suggest that mixing of B20 from certified B100 fuel may lead to oxidation of unsaturated FAMES and subsequent higher ROS formation potential. Future work should examine how the detailed chemical composition of biodiesel exhaust PM, especially when waste oil B100 is blended with petrodiesel at 20 % v/v, may be related to DTT consumption or other metrics for ROS formation potential. Further, future emissions studies should provide information on property differences between Bxx blends and the neat B100 fuel that result not only from biodiesel storage, but from fuel handling. View the NCST Project Webpage

The purpose of the study was to determine the effect of the fuel used in the spark-ignition engine of the selected vehicle on the characteristics of maximum torque and power at the crankshaft of the engine as a function of crankshaft speed and the composition of exhaust gas. The vehicle engine was tested on a stand equipped with V-tech VT-2/B2 chassis dynamometer, MAHA MET 6.3 exhaust gas analyzer and engine parameter monitoring system in compliance with OBD standard. The tests used two commercial fuels with different test octane number (RON) values of 95 and 100 octanes. Measurement of the characteristics of the maximum torque, power on the crankshaft and the total power losses in the drive system, the contact of the wheels with the rollers of the dynamometer and the dynamometer as a function of the crankshaft rotational speed was carried out using the acceleration method with a dynamic load comprising the braking torque of the rotating masses and the electro-swirl brake. On the basis of the test results, engine and drive system parameters of the vehicle, a set of measuring points determining the values of the engine crankshaft speed and the torque generated by the engine crankshaft was determined, using the software for generating driving test runs "the calculation of gearshift points for the WLTC cycle". The parameters of the selected engine operating conditions were within the ranges specified by the software for generating the selected test runs. The content of selected exhaust gas components (carbon monoxide (CO), carbon dioxide (CO2), other hydrocarbons (HC), oxygen (O2), coefficient, nitrogen oxides (NO) and nitrogen dioxide (NO2)) was measured for the selected operating parameters of the vehicle for the tested fuels. On the basis of the results of the toxicity measurements, analytical models determining the content of individual components in the exhaust gases as a function of the crankshaft rotational speed and the torque generated on the crankshaft and software simulating the exhaust emissions of the selected vehicle moving under dynamic conditions were developed. [ABSTRACT FROM AUTHOR]

Biofuels are the most essential types of alternative fuels, which currently have significant potential to reduce CO2 emissions compared to fossil fuels. Methanol is a more efficient fuel than petrol due to its physicochemical properties, such as a higher latent heat of vaporization, research octane number, and heat of combustion of the fuel–air mixture. Also, biomethanol is cheaper than traditional petrol and diesel fuel for agricultural countries. The authors have proposed a new approach to improve the characteristics and efficiency of methanol diesel engines by using biomethanol mixed with hydrogen instead of pure biomethanol. Using a hydrogen–biomethanol mixture in modern engines is an effective method because hydrogen is a carbon-free, low-ignition, highest-flame-rate, high-octane fuel. A small quantity of hydrogen added to biomethanol and its combustion in an engine with a heat exchanger increases the combustion temperature and heat release, increases engine power, and reduces fuel consumption. This article presents experimental results of methanol combustion and a hydrogen-in-methanol mixture if hydrogen was retained due to the utilization of the heat of the exhaust gases. The tests were carried on a single-cylinder experimental engine with an injection of liquid methanol and gaseous hydrogen mixtures. The experiments showed that green hydrogen generated onboard the car due to the utilization of heat significantly reduced fuel costs of engines of vehicles and technological installations. It was established a hydrogen gaseous mixture addition of up to 5% by mass to methanol requires a corresponding change in the coefficient of excess air to λ = 1.25. Also, using an additional hydrogen mixture requires adjustment at the ignition moment in the direction of its decrease by 4–5 degrees of the engine crankshaft. Hydrogen gas mixture addition reduced methanol consumption, reaching a maximum reduction of 24%. The maximum increase in power was 30.5% based on experimental data. The reduction in the specified fuel consumption, obtained after experimental tests of the methanol research engine on the stand, can be implemented on the vehicle engines and technological installations equipped with an onboard heat recovery system. Such a system, due to the utilization of heat and the supply of additional hydrogen, can be implemented for engines that work on any alternative or traditional fuels. [ABSTRACT FROM AUTHOR]

The paper shows that the efficiency of the machine and tractor fleet is significantly influenced by operating conditions. It is known that the harsher the operating conditions, particularly those related to climate, the higher the frequency of failures, which, in turn, results in the reduced durability and efficiency of the equipment. One way to mitigate failures and power losses in the motor-transmission unit, as well as improve fuel efficiency, is by utilizing the waste heat from the internal combustion engine. This approach ensures an optimal temperature in the main units of the machinery at negative ambient temperatures. (Research purpose) The research aims to develop a technological scheme for utilizing waste heat from the internal combustion engine, specifically the heat from exhaust gases, to maintain the optimal temperature in the main units of the machine and tractor unit. (Materials and methods) The potential for using exhaust gas heat in the proposed scheme was studied and assessed using an experimental setup. The results were processed using the exergy research method. (Results and discussion) It is found that the power of the exhaust gas heat fl w at various engine operating modes provides favorable conditions for its utilization in the proposed scheme. Based on the research results, a system for maintaining a set temperature regime in the main units and trailer unit of a self-propelled machine was developed and patented. (Conclusions) The presence of significant kinetic and thermal energy in the exhaust gases enables its secondary use. A technological scheme for utilizing the heat of exhaust gases from internal combustion engines has been developed as a system for maintaining a set temperature regime in the main units and trailer unit of a self-propelled machine. The application of the developed system will maximize the utilization coefficient of the heat released during fuel combustion in the engine.

The article presents the results of testing the validity of the hypothesis about the possibility of isolating the exhaust gases of the internal combustion engine (exhaust gas source). The objective was to conduct an experimental study of the "exhaust gas source - storage tank" system. In the experimental study, the following was performed: establishment of influencing factors and output parameters; selecting the number of experiments; methods and means of measurement; conducting an experiment at the stand. [ABSTRACT FROM AUTHOR]

At the Chelyabinsk Zinc Plant of the Ural Mining and Metallurgical Company, oxidized zinc and lead-containing raw materials are processed in Waelz kilns. Waelz oxides, containing chlorine and fluorine, are calcined in tubular rotary kilns. The results of studies on the halide removal are provided – in the calcination process, chlorine is removed mainly in the form of zinc and lead chlorides, while in calcined oxide, chlorine remains in multicomponent difficult-to-digest substances; – at an increase in the specific volume of exhaust gases from 300 to 820 m3/kg of chlorine, charged into the kiln, the residual chlorine content in the calcined Waelz oxide decreases from 5.2 to 0.05%; – at the pilot kiln (length of 1.9 m, diameter of 0.2 m), tests were carried out to determine the specific volumes of exhaust gases and the gas flow velocity. The following results were established – within 1 h from the beginning of the experiment, the reaction proceeds in the diffusion-kinetic mode; – when the velocity of gases at the outlet of the kiln decreases to 3 m/s, the sublimation occurs in the forced diffusion mode. This correlates with the data on the velocity of gases in a real industrial kiln; – the capacity of the industrial kiln (L = 41 m, D = 2.5 m) is 8.0 t/h of waelz oxide using the calcined product (chlorine content of 0.05%) with a volume of kiln exhaust gases of 12–18 thous. Nm3/h at a temperature of 500–550 °C and the size of the charged waelz oxide pellets of 6–10 mm. When the pellet size is reduced to 2–4 mm, the kiln capacity increases from 8 to 10 t/h, while the chlorine content decreases from 0.05 to 0.04%. On the basis of pilot tests, a cyclone cooler, capable of cooling 18,000–19,000 Nm3/h of gases with a temperature of 600 °C, was developed for the kiln. [ABSTRACT FROM AUTHOR]

The paper studies the thermal schemes and construction characteristics of gas turbine units. The pros and cons of the considered turbines are compared with steam turbine units. At the same time, the amount of nitrogen gas coming out of the gas turbine and a steam turbine of the same power is calculated and a comparative analysis is given. It is found that the amount of nitrogen gas coming out of the gas turbine is 4 times less than that of the steam turbine. [ABSTRACT FROM AUTHOR]

Relevance. The need to ensure safe working conditions in the working areas of underground mines. Stagnant zones with low air velocities can be formed in large section blind heading behind the ore bulk when ore is shipped by mining machines. There is a possibility of the formation of local gas accumulations and their abrupt removal later in such stagnant zones due to the unsteadiness of accumulation and transfer of gas impurities in a blind heading. A sharp removal of gas will lead to contamination of the load-haul-dump operators’ workplace. Aim. To identify removal of exhaust gases in large section blind headings in conditions of changing ore load size. Objects. Large section blind headings with of complex geometry. Methods. Three-dimensional numerical simulation of unsteady turbulent flow of a gas-air mixture in the Ansys CFX, visualization and analysis of simulation data in the Wolfram Mathematica. Results. The paper presents the results of mathematical modeling of ventilation of large section blind headings of complex geometry under conditions of changing ore load size formed during mining operations by the load-haul-dump machines with an internal combustion engine. It is shown that either a single vortex is formed that ventilates the blind headings space, or a stagnant zone behind the bulk ore, which is characterized by a relatively low intensity of mass transfer. Vortex formation depends on the height of the ore bulk. The authors have obtained the dependences of the change in the average concentration of exhaust gases at the outlet of the blind headings space on the operating time of the machine. They determined the dependence of the correction volume coefficient on the geometric parameters of the blind headings. An analytical model of the removal of gases from the blind headings space under conditions of changing bulk ore volume is obtained. The expression of increment in gas concentration on an operator’s workplace makes it possible to derive formula to find maximum time of load-haul dump operation in a stope such that gas concentration is never higher than maximum allowable concentration.

The increasing complex geological and hydrogeological conditions ore deposit mining, deeper excavation sites, and ambitious business expansion strategies, necessitate the use of high-performance, heavy-duty self-propelled machinery and winning equipment. Such activities significantly strain mine ventilation systems and demand innovative safety measures during mining. This study assesses the influence of interconnected production variables on the aerological safety of mining operations. It provides real-world data on emissions from diverse sources within mines. The analysis includes an examination of current methodologies for estimating the air volume needed to dilute exhaust gases from diesel-powered machinery. Through numerical simulation that accounts for changes over time, the study was able to predict how exhaust gas concentrations would disperse within mines. These theoretical findings were then confirmed through empirical observations made in actual mining setting The field studies conducted, alongside their thorough analysis, underscored the necessity for adopting new, more sophisticated approaches to calculate airflow requirements in mines operating ICE machinery. A particular methodology developed by the MMI of the NUST MISIS (hereinafter referred to as the Methodology) was put forward as the primary tool for this purpose. The Methodology’s precision and benefits were closely scrutinized, revealing its effectiveness in ensuring aerological safety in mines.

The object of research is the environmental parameters of a reciprocating engine when using a synthesis gas additive to the main fuel. The research is aimed at solving the problem of reducing the concentration of harmful components in the exhaust gases of an internal combustion engine by adding synthesis gas to the main fuel. Experimentally, the dependences of the effect of the addition of synthesis gas to ethanol on the change in the environmental performance of a piston engine with spark ignition were obtained. The positive effect of the addition of synthesis gas obtained by thermochemical conversion to ethanol in an amount of up to 5 % by weight on the environmental performance of a spark-ignition piston engine was established. Provided that the engine achieves the same effective power, the use of a synthesis gas additive to the main fuel made it possible to reduce the concentration of CO by 61.5 % and CH by 51.3 % in the exhaust gases. no more than 25–30 words The addition of synthesis gas contributed to the formation of radicals that activate oxidation chain reactions, and also made it possible to increase the normal combustion rate of the fuel-air mixture by 6.25 %. This ensures normal engine operation on a leaner fuel-air mixture (α=1.21) without deterioration of environmental, energy and economic performance. no more than 25-30 words The simultaneous reduction of the concentration of harmful components in the exhaust gases and engine efficiency can be achieved by using fuels with a wide concentration limit of ignition and high combustion rate in a lean mixture. The experimental data obtained can be used in the design or modernization of transport and stationary power plants with internal combustion engines as an approach to meet ever-increasing environmental standards. [ABSTRACT FROM AUTHOR]

The article presents experimental research and calculations of spark ignition engine indicators, using hydrogen-containing H 2 /O 2 gas, when the engine is running at low power. The engine throttle was opened 8°, the amount of H 2 /O 2 gas was increased from 0 to 7.9 % of the mass of gasoline, the stoichiometric (λ = 1) air/fuel ratio was maintained. Research shows that the addition of the H 2 /O 2 gas leads a great influence on the energetic and ecologic indicators of the engine and this depends on the change in the combustion process and the change in the composition of the fuel. The calculation methodology of the combustion process when the engine is fuelled with pure gasoline and with additives of hydrogen-containing gas presented. Presented results how addition of H 2 /O 2 leads to a reduction in the duration of the combustion process and also has a significant effect on a faster rise of combustion pressure and temperature. Shorter combustion duration leads to a rise of the indicated efficiency of the engine, the heat utilisation factor and an increase in the indicated power. As a result of bench tests, an increase in the effective power and a decrease in the brake-specific fuel consumption of the engine were found. When assessing the influence of H 2 /O 2 on the concentration of CO 2 in the exhaust gas, no decreases was not observed, as hydrogen improves the combustion process. Only the concentration of incomplete combustion process products (e.g., HC) decreases, but the concentration of NO x increases at the same time. • Study of indicators of the engine operating at low power by changing the amount of H 2 /O 2 in a wide range. • Described method for calculating the indicated engine parameters, taking into account the addition of H 2 /O 2. • Determined indicators of the combustion process for the gasoline engine operating with the H2/O2 additive. • The addition of an H2/O2 (7.9% of mass) enhances heat usage efficiency and raises the indicated efficiency to 13.9%. • The H 2 /O 2 additive reduces BSFC but does not significantly affect the CO 2 emissions of the SI engine. [ABSTRACT FROM AUTHOR]

The increased concentration of CO2 in the atmosphere has a strong impact on global warming. Therefore, efficient technologies must be used to reduce CO2 emissions. One of the methods is the biofixation of CO2 by microalgae and cyanobacteria. This is now a widely described technology that can improve the economics of biomass production and reduce CO2 emissions. There are no reports on the possibility of using it to clean exhaust gases from biogas combustion. The aim of the research was to determine the possibility of using Arthrospira platensis cultures to remove CO2 from biogas combustion. The efficiency of biomass production and the effectiveness of biological CO2 fixation were evaluated. The use of exhaust gases led to a more efficient increase in cyanobacterial biomass. The growth rate in the exponential phase was 209 ± 17 mgVS/L·day, allowing a biomass concentration of 2040 ± 49 mgVS/L. However, the use of exhaust gases led to a decrease in the pH of the culture medium and a rapid decline in the Arthrospira platensis population. The cyanobacteria effectively fixed CO2, and its concentration was limited from 13 ± 1% to 1.3 ± 0.7%. There was no influence of the exhaust gases on changes in the qualitative composition of the cyanobacterial biomass. In the culture fed with exhaust gas, the A. platensis population quickly entered the death phase, which requires close monitoring. This is an important indication for potential operators of large-scale photobioreactors. [ABSTRACT FROM AUTHOR]

For the past few years, the energy demand has been raised progressively all over the world. Numerous extensive studies have been conducted to reduce the rate of emission in diverse alternative fuels. However, currently numerous investigations have been undertaken to diminish the harmful impact of the exhaustion of gas emissions from the utilization of diesel, Liquefied Petroleum Gas (LPG), and gasoline fuels. Hence, a novel triple fuel system (i.e. petrol, diesel, and LPG) is proposed based on three different analyses, namely energy, exergy, and emission at diverse load (kg) conditions. Nonetheless, the validations of each method are performed by single-cylinder four-stroke diesel engines at optimized conditions. Moreover, the analyses are performed at a constant speed rate of 1500rpm, with six diverse engine loads (kg) of about (2.5, 5, 7.5, 10, 12.5, and 13.50 kg). Various measurable factors such as emission rate, heat transfer rate, and cylinder pressure are determined to estimate the steady state condition. Finally, various parameters such as brake thermal efficiency, specific fuel consumption, and exhaust gas analysis are performed and compared with single fuel, dual fuel, and the proposed triple fuel modes to determine the efficiency of the system.

Satisfying the demand for goods requires the movement of commercial and private vehicles, which are responsible for multiple negative impacts including noise, emissions, and traffic congestion. While efficiency is crucial for sustainable and profitable freight transportation, operations are typically inefficient with respect to emissions and social impacts. The reasons for such inefficiency are diverse, including the need for several attempts to complete a delivery and the under usage of vehicle capacity. The arrival of zero-emission and near-zero-emission medium- and heavy-duty vehicles may reduce (tailpipe) emissions. Multiple government agencies have supported the development and promotion of cleaner vehicles through strategies such as economic incentives to support purchases and disincentives to using internal combustion engine vehicles. However, small- and mediumsized companies face challenges in adopting cleaner vehicles, either because of high purchase costs or because the volume of their operations may not justify the expense. To address this issue, this work evaluates cooperative strategies between noncompeting companies that would exploit economies of scale through the sharing of vehicle capacities in joint routing. The work develops a decision support tool named Cargo Aggregator Beta 1.0, which provides companies willing to cooperate with an efficient joint route to pick-up and deliver cargo from different origins and destinations. The tool, based on an extension of the vehicle routing problem, allows users to consider different vehicle capacities, decide on charging and/or refueling points, consider multiple depots, and guarantee the completion of all deliveries in a general time window. The tool can be used to better understand the impact of sustainability policies that would limit the amount of pollutant emissions generated, or policies that seek to restrict fleet composition. Numerical analyses using study cases in California show the potential benefits of implementing these collaborations in reducing both costs and emissions.

This study aims to solve the problem of decarbonization of industrial emissions from metallurgical furnaces using the process of carbothermic reduction of silicon in ore-thermal furnaces (OTFs) as an example. The methods used for cleaning the exhaust gases cannot completely ensure the processing of carbonaceous emissions. We propose a method of using conversion-type gasifiers for carbon reduction when processing combustion products of exothermic reactions in metallurgical units. Computational fluid dynamics and mathematical modeling are applied to confirm the feasibility of the proposed solution. As part of the scientific problem of decarbonization associated with reducing the carbon footprint, the thermodynamic processes in changing the dust–gas medium composition based on the solution of fundamental principles related to the modification of the Bell–Boudouard equation have been analyzed. Consequently, the calculated value of the carbon dioxide flow rate can become the initial parameter for the calculation model of a conversion gasifier for an OTF in the production of metallurgical-grade silicon. [ABSTRACT FROM AUTHOR]

This study explores strategies to enhance the efficiency of marine technical equipment through the adoption of lowsulfur marine fuels. The investigation incorporates a comprehensive analysis, encompassing enthalpy change calculations and thermal efficiency estimates at various temperature differentials. These calculations shed light on the impact of the specific heat capacity of low sulfur marine fuels, a crucial factor in understanding combustion characteristics. Furthermore, provides an assessment of the efficiency of converting heat to mechanical energy, offering valuable insights for optimizing equipment performance. The outcomes of this research contribute to a broader strategy aimed at bolstering the environmental sustainability and efficiency of marine propulsion systems. By scrutinizing the utilization of low sulfur marine fuels, the study seeks to inform decision-making processes by pinpointing temperature ranges that maximize efficiency. The findings also highlight areas with potential for improvement in the performance of marine diesel engines. This holistic approach is integral to fostering advancements in both environmental responsibility and operational effectiveness within the maritime industry. [ABSTRACT FROM AUTHOR]

The paper considers the use of exhaust gas heat in modular power plants. In this regard, fuel consumption at power plants will decrease, efficiency of power plant will increase the emission of harmful gases into the atmosphere and environmental burden will reduce. [ABSTRACT FROM AUTHOR]

Despite the widespread use of renewable and green energy, the demand for fossil fuels is also rising due to increasing global energy demand. Therefore, unconventional solutions, with safe environmental impacts, are being pursued to solve this problem. Instead of getting rid of the exhaust gases in the surroundings, one solution might be to inject them with the oxidizer into the oil reservoir, to initiate an in-situ combustion (ISC) process to enhance oil recovery. A numerical study of a 1-D combustion tube has been conducted and validated to simulate the in-situ combustion process using enriched air as the oxidizer. The effects of injecting exhaust gases with the oxidizer are studied. Different ratios of oxygen to nitrogen are used in the enriched air as well as different ratios of exhaust gases. If enriched air which is mostly oxygen, i.e. 95% O2 +5%N2, is used, it is found that replacing 10% of the enriched air with exhaust gases can increase the oil recovery factor (ORF) from 94.7% to 94.9% and replacing 20% can improve oil recovery to 95.1%. For another enriched air, 60% O2 +30% N2, it is found that replacing portions of the enriched air with exhaust gases will reduce the oil recovery factor. In all previous cases, it was found that replacing the proportions of enriched air with exhaust gases reduces the amount of fuel burned and increases hydrogen production. [ABSTRACT FROM AUTHOR]

The single-cylinder, four-stroke, overhead valve Biggs Stratton engine was studied for the possible toxinity with the view of solving the environmental pollution problem related to the internal combustion engine emissions. As an assessment of toxicity, the data recorded (INFRACAR 5M3T) in the exhaust gases of the power unit NOx, CO and CH was used. Evaluation of the toxicity of the engine running under load was carried out by testing (CARTEC LPS 2510 dynamometer) an engine-equipped vehicle of simplified design (buggy). It was shown that the presence of CO, CH and NOx in the exhaust gases is affected not only by the presence of alcohol in gasoline, but also by the crankshaft speed. It was found that the proportion of CH in the exhaust gases of the power unit running on gasoline is lower than the maximum allowable content of hydrocarbons in the exhaust gases of gasoline engines not equipped with a neutralization system. According to the data obtained from bench tests, it follows that the proportion of CH in the exhaust gases of a gasoline-fueled engine is on average 48% higher than in the exhaust gases of an engine fed with a gasoline-alcohol mixture. It was shown that a significant increase in power at the wheel does not lead to a sharp increase in the CH content in the exhaust gases. The proportion of CH in the exhaust gases in the obtained speed range is a constant value.

There is much uncertainty over whether on-demand ridehailing services, namely Uber and Lyft, will worsen or alleviate existing transportation problems such as congestion, emissions, and inequities in access and mobility. For policymakers, transportation planners, and others in the transportation arena, these unknowns have created uncertainty over which policies would best steer ridehailing toward equitable and sustainable outcomes. To address these uncertainties, researchers at UC Davis assessed how stakeholders from different groups view the possible impacts of ridehailing and the policies that might best address those impacts. The researchers evaluated these questions through in-depth interviews with stakeholders from 38 agencies and organizations throughout California. Interviewees included transportation planners, members of state agencies, and representatives from non-profit organizations and the ridehailing industry. This policy brief summarizes those interviews, as well as findings from the research.View the NCST Project Webpage

The selection of optimal measures for reducing the environmental impact of diesel engines is considered. The relative variation in the fuel consumption and nitrogen oxide emissions is studied for the 4400‑kW 12FT26.5/31 engine (produced by Kolomensky Zavod). The proposed selection strategy may be used in development tests of new engine designs. [ABSTRACT FROM AUTHOR]

Fire whirls are frequently spotted during forest fires in which unburnt or half burnt fuel around the fire can be seen rotating along with the whirl. The fuel rotation inside the whirl affects the fire characteristics compared to the stationary burning condition. In this work such variation in Mass Burning Rate (MBR), centerline field temperature, radiative heat flux, flame length, flame width, flame wandering and emission of laboratory-scale fire whirl are studied. For a constant pool diameter (d), the MBR ( m ˙ ″ ) of fire whirls depends on the imposed rotations/circulation (Γ). A correlation m ˙ ″ = 0.05Γ0.94 is proposed to relate the mass loss flux with imposed circulation. Whereas, with fuel rotation, mass loss flux decreased up to 20% due to the change in bottom boundary conditions. As fire whirl height (Hf) is a function of MBR and imposed circulation, the correlation H f ∗ = K. ( Q ∗ ∙. Γ ∗ 2) m has been modified with the help of experimental data, where constants K and m closely resemble the literature data. To quantify flame wandering a parameter Appearance Probability (AP) was introduced and calculated. The AP—time plot indicate that the imposed rotation caused the flame to wander, eventually increasing the centerline field temperature by 20%. Finally, the measurement of fire effluents suggests that CO and CO2 concentration increases with imposed circulation in the fire whirls and instantly reaches the Threshold Level Values for a short time exposure limit (TLV-STEL). [ABSTRACT FROM AUTHOR]

The processes of concentration of dilute solutions of sulfuric acid (H2SO4), in particular hydrolytic sulfuric acid for the production of pigment titanium (IV) oxide, were analyzed. It is proposed to concentrate solutions of Н2SO4 by evaporation in direct contact of acid droplets with hot industrial exhaust gases. The mathematical model of the evaporation of Н2SO4 drops in a hot gas stream, which used for the calculations, makes it possible to calculate the mass, temperature, velocity, and coordinates of the drop at any time with sufficient accuracy. However, the calculations are difficult, cumbersome and require multiple processing of large data sets. Therefore, the aim of the article was to approximate the calculated technological parameters of sulfuric acid droplet evaporation by obtaining simple mathematical dependencies. The mathematical dependences of the mass transfer coefficient and the distance traveled by a drop of Н2SO4 during evaporation on air temperature and drop diameter were obtained. It has been established that technologically expedient evaporation of Н2SO4 drops with a diameter of ≤ 0.5·10-3 m in traditional devices leads to significant droplet loss, increased corrosion of equipment, etc. So, in order to practically implement the technology of evaporation of HSA solutions with industrial exhaust gases, it is necessary to change the technological mode of operation of the evaporator and the design of the main device. It is proposed to use the obtained results to study the methods of intensification of the evaporation process, selecting a modern mass transfer apparatus, developing a technology for utilizing hydrolytic sulfuric acid and producing pigment titanium (IV) oxide. [ABSTRACT FROM AUTHOR]

Parking has long been an urban planning challenge. Providing parking in city centers is land-intensive and expensive. Moreover, drivers searching for scarce parking can increase congestion, vehicle miles traveled (VMT), and greenhouse gas (GHG) emissions. Use of automated vehicles to drop off and pick up travelers could reduce the demand for parking, which could reduce VMT and associated emissions and allow urban spaces currently used for parking to be converted to more beneficial uses. However, automated vehicles could also have negative consequences. They could generate empty vehicle travel and more cross-traffic movements due to drop-offs and pick-ups which could increase congestion, VMT, and GHG emissions.Researchers at the University of California, Davis modeled the travel effects of changes in drop-off and pick-up activity and parking supply that might be triggered by widespread automated vehicle use in San Francisco’s city center. A primary goal of this research was to determine an optimal level of automated vehicle adoption that minimizes negative consequences. The researchers also modeled methods to control these negative consequences, including expanding drop-off and pick-up zones and imposing auto pricing policies to curb demand. This policy brief summarizes the findings from that research and provides policy implications.View the NCST Project Webpage

The potential for automated vehicles (AVs) to reduce parking in city centers has generated much excitement among urban planners. AVs could drop-off (DO) and pick-up (PU) passengers in areas where parking costs are high: personal AVs could return home or park in less expensive locations, and shared AVs could serve other passengers. Reduced on-street and off-street parking present numerous opportunities for redevelopment that could improve the livability of cities, for example, more street and sidewalk space for pedestrian and bicycle travel. However, reduced demand for parking would be accompanied by increased demand for curbside DO/PU space with related movements to enter and exit the flow of traffic. This change could be particularly challenging for traffic flows in downtown urban areas during peak hours, where high volumes of DOs and PUs are likely to occur. Only limited research examines the travel effects of a shift from parking to DO/PU travel and the impact of changes in parking supply. This study uses a microscopic road traffic model with local travel activity data to simulate personal AV parking scenarios in San Francisco's downtown central business district. These scenarios vary (1) the demand for DO and PU travel versus parking, (2) the supply of on-street and off-street parking, and (3) the total demand for parking and DO/PU travel due to an increase in the cost of travel to the central business district.View the NCST Project Webpage

This study investigates how stakeholders throughout California view the potential impacts of ridehailing services, such as Uber or Lyft, on transportation systems, and how to address such impacts. The stakeholders surveyed included city planning agencies, regional transportation planning agencies, metropolitan planning organizations, state agencies, ridehailing service providers, interest groups, and non-profits. Ridehailing is one of several emerging shared use mobility alternatives, poised to impact transportation systems, for better or worse. For better, if these new services catalyze the development and maturation of well-integrated multi-model transportation systems that serve all travelers and reduce vehicle miles traveled (VMT) and transportation emissions. For worse, if these new services serve merely as a less expensive taxi, allowing more people to forego alternative modes of transportation like public transit and biking, thereby leading to increases in VMT, emissions, and congestion. The high degree of uncertainty surrounding the impacts of these services presents challenges to stakeholders involved in transportation planning and policy making. Through interviews, the researchers investigated the viewpoints of 42 transportation stakeholders throughout the state of California. They find that the diversity of interviewees is reflected in the sentiments they have about ridehailing, what issues are important and potential obstacles to achieving positive outcomes. Nonetheless, interviewees agree that regulations should balance local control with state level guidance.View the NCST Project Webpage

To save the environment and utilize the waste heat associated with exhaust gases of internal combustion engines, it is crucial to design an efficient system that can recover this heat loss and convert it into useful energy. This study is devoted to developing, through an experimental approach, a practical technical solution to minimize the waste heat of the exhaust gases and convert it into a source of power for further applications in the vehicle. Six thermoelectric generators (TEG1-1263-4.3) were attached to the exhaust pipe in an arrangement of three connected in parallel and three connected in series. The thermoelectric generators were in a square shape of size 30 mm x 30 mm, and operated at a maximum temperature of 320. The experiments were conducted for a vehicle speed limit between (10 km/h - 60 km/h). It has been found that at a vehicle speed of 55 km/h, the exhaust pipe surface temperature reached approximately 116oC. For six models of TEGs, the output voltage was 4.13 volts. And the system efficiency was found to vary between 3.6% -15.9%, depending on the surface temperature of the exhaust pipe, i.e., the surface temperature that is in contact with the hot side of the thermoelectric generators. Such outputs refer to the efficiency of TEGs to be used as a heat recovery system. Furthermore, the produced power can be used for feeding other applications within the vehicle, such as using a small fridge for a cooling process.

Studies of the physicochemical properties of traditional gasoline (G), innovative gasoline (IG) and high-quality gasoline (HQG) have been carried out. The purpose of this work was to analyze the physicochemical properties of innovative, high-quality grades of gasoline, to compare the performance of these fuels with those of conventional fuel that does not contain substances that improve the operational and environmental qualities. The research of the properties of gasolines was carried out using an automatic apparatus for distillation of petroleum products ARNS-1E, indicator (octanometer) OKTAN-IM, gas analyzer INFRACAR 5M3T, single-cylinder, 4-stroke, overhead valve engine (Biggs Stratton). It has been established that the density of gasolines, the final boiling point, the residue in the flask and the acidity correspond to the GOST standards. A six-month storage period for fuel samples does not affect the parameters of the fuel, its physical and chemical stability. It is shown that substances that improve the properties of innovative and high-quality fuels do not affect the result of measuring the octane number of gasoline. It has been established that the chemical stability of improved grades of gasoline is higher than that of traditional fuel. It is shown that innovative and high-quality gasoline is superior to gasolines that do not contain combustion-improving substances in terms of combustion efficiency. A similar conclusion was made for nitrogen oxides, the content of which is associated with the presence in gasoline of components that increase the temperature of gases that occur in the combustion chamber of the power unit.

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In the United States, vehicle emissions are responsible for 29% of total greenhouse gas (GHG) emissions with the majority of these coming from light-duty vehicles. To reduce GHG emissions, the U.S. has adopted policies to support the development and deployment of low-carbon fuels and zero emission vehicles (ZEVs—e.g., plug-in hybrid electric vehicles [PHEVs] and battery electric vehicles [EVs]).Most current policies focus on emissions from vehicle operation only, omitting significant contributions from vehicle production and other parts of the vehicle and energy life cycle.GHG emissions from vehicle operation and even from operation plus production are almost always lower for EVs than for conventional internal combustion engine vehicles (see Figure). However, as EVs become more efficient, low-carbon electricity becomes more common, and the size of the global EV fleet increases, emissions from production and other non-operation parts of the life cycle become increasingly important.Researchers at UC Davis studied: (i) the effect of different factors on life cycle emissions; (ii) the impact of excluding life cycle emissions from policies; and (iii) potential strategies that might be used to effectively incorporate life cycle emissions in light-duty vehicle GHG policy. This policy brief summarizes the findings from that project.View the NCST Project Webpage

In this study, a second-by-second (SbS) data set obtained from monitoring vehicle emissions over a series of 75 test runs from 2 test vehicles (a conventional vehicle (CV) and a hybrid-electric vehicle (HEV)) over an 18-month period in 2010-2011 during real-world on-road operations on a specified 32-mile route in Chittenden County, Vermont was used in an innovative new method of analysis to assess emissions differences between the two propulsion systems and attribute these differences to physical roadway/infrastructure characteristics. The K-S test was used to assess the difference between the cumulative distributions of the CV and HEV emissions samples on each link, and the K-S test statistic was regressed against the full set of roadway link characteristics. The regression results allowed the team to identify specific roadway characteristics that contribute to emissions differences between the vehicle types. Overall, the models that included maximum grade and intersection control type performed best, however speed limit and horizontal curvature were also shown to be important. The performance differences identified in this project confirm that engine controls that are responsive to roadway characteristics are necessary.View the NCST Project Webpage

California has a range of existing and proposed targets toward a low carbon future. This paper summarizes an analytical review, focused on modeling approaches and what is known about their feasibility and cost. The findings in this paper are based on the Climate Change Policy Modeling (CCPM) forum, which included modelers, policy makers and stakeholders evaluating targets and pathways to low-carbon futures and identifying required policies to achieve goals. The third forum, CCPM-3, was on May 14th, 2018, at the University of California, Davis and provided critical discussion and a gathering of the key experts in this topic area This report builds on the findings of CCPM and integrates with other literature where possible. It includes a review of the CO2-relevant targets, discussion of studies and modeling efforts to assess meeting such targets, including feasibility and cost. This includes analysis in the transportation and energy sectors, as well as land use and carbon sequestration.

Driver behavior has a significant impact on vehicle fuel economy and emissions. Eco-driving refers to anything a driver can do to improve on-road fuel economy. The most common strategy used to promote eco-driving is an in-vehicle display that provides the driver with feedback about their fuel efficiency, typically in real-time.This policy brief summarizes findings from an extensive review and analysis of many studies of eco-driving feedback conducted to determine the average impact of feedback on fuel economy and improve understanding of what types of feedback are most effective. The study provides the most accurate estimate to-date of the average impact of in-vehicle feedback on fuel economy and summarizes the current state of knowledge regarding characteristics of eco-driving feedback interventions that determine effectiveness.View the NCST Project Webpage

Introduction. Alternative fuels in IC-engines make it possible to reduce the harmful effects of exhaust gases on the environment without the use of expensive cleaning systems, diversify the fuel market, and reduce the consumption of non-renewable energy recourses, while research aimed at studying the use of alternative fuels makes it possible to find optimal options for replacing non-renewable raw materials. The purpose of the work is to study the effect of using ethanol in a standard tractor diesel engine with volumetric mixing and combustion from flare resulting from the autoignition of a rapeseed oil pilot portion and to optimize separate cyclic fuel deliveries to obtain maximum energy and environmental effect. Materials and Methods. The article deals with the description of the results of the use of rapeseed oil and ethanol in a serial tractor diesel engine of dimension 2F 10.5/12.0 with separate fuel injection directly into the combustion chamber. In the course of experimental studies, the working process was indicated by a piezo quartz pressure sensor installed in the cylinder head, fuel and air consumption were measured, and samples of exhaust gases to study the gas composition and determine the content of toxic components and smokiness were taken. Results. The exact ethanol and rapeseed oil delivery was determined; the values of the average effective pressure, the average temperature of gases in the cylinder, and active and full heat generation were obtained. It is shown that with an increase in the cyclic ethanol delivery, the proportion of heat from kinetic combustion increases, while the diesel process is characterized by an increase in the proportion of diffusion combustion when the load increases. The analysis of the processes inside the cylinder when the engine runs on ethanol and rapeseed oil in comparison with the traditional diesel process is carried out. Discussion and Conclusion. The use of rapeseed oil and ethanol can completely replace the traditional fuel of petroleum origin for an operating diesel engine by installing additional fuel equipment and modifying the head of cylinder block through mounting an additional nozzle. In this case, the environmental performance of the diesel engine improves significantly.

Introduction. The tasks of increasing energy saving in heating systems for passenger cars of diesel trains are currently relevant. As an alternative source of energy for these systems, the possibility of using the waste heat of the diesel locomotive engine is analysed.Materials and methods. The article provides an analysis of the engine waste heat sources, cooling water and exhaust gases. A schematic diagram of exhaust gas heat exchanger for its use in the heating system of passenger cars has been deve loped. As a possible heat-exchange surface of the waste heat exchanger, plate-ribbed, coiled and tube surfaces with longitudinal boundary layer turbulators are proposed. The required area of this surface for the maximum power of the heating system for a passenger train is determined.Results. The article shows the possibility of using engine exhaust heat in the heating system of a 15-car passenger train without involving third-party energy sources.Discussion and conclusion. The obtained results demonstrate a sufficient potential for increasing the efficiency of using the diesel engine fuel energy when utilising its waste heat for the heating system of passenger cars. The selection of a waste heat exchanger is justified based on a performance of 50 % of the peak load on the heating system at the middle position of the controller.

It was noted that increased soil moisture worsens the quality of harvesting root crops due to a decrease in the completeness of separation. To increase the separating capacity of a slotted cleaner for root crops, it was proposed to improve the heating of the separating surface with hot exhaust gas. (Research purpose) To optimize the design and technological parameters of an exhaust gas heat separation system of the sugar beet harvester power plant. (Materials and methods) Federal Scientific Agroengineering Center VIM developed an exhaust gas heat separation system for harvesting root crops and potatoes in high moisture conditions using the heat of the harvester power plant exhaust gases. The cleaning quality of the separating system of a self-propelled sugar beet harvester was determined under the gradual engine load from 0 to 100 percent of the nominal rated power. The temperature of the exhaust gases was measured with the assumption of changes in the engine load and its effective power. (Results and discussion) The experiment revealed an increase in the completeness of the separation of a root crops heap from 96.0 to 98.8 percent at 26-32 percent soil moisture due to the separation system in the form of a cleaning star, which uses the heat of the engine exhaust gases. The established optimal values of the factors under consideration are as follows: the separating star rotation rate is 21.8 revolutions per minute, the distance between the separating star and the deflector is 128.4 millimeters. (Conclusions) It was determined that the high quality of the technological process of root crops harvesting in high soil moisture conditions ensuring a 97-percent separation efficiency is possible if optimize the separating device design and technological parameters and maintain the separating star rotation rate at 20-22 revolutions per minute and the distance between the separating star and the deflector within 120-140 millimeters. The authors noted the prospects of developing this system and the need for theoretical and experimental studies to improve the design and technological process of the harvester separating system.

The motivations for this study stem from an uncertainty about whether on-demand ridehailing services such as Uber, Lyft and others, will exacerbate existing transportation issues, or help alleviate them. To that end, the goals of the project were to learn about the perspectives of stakeholders from a variety of sectors, on their reactions to policies and other actions that might enable on-demand services to help alleviate existing transportation issues including congestion, emissions and inequality of access and mobility.This study aims to address the following three questions: How well do stakeholders in different sectors and regions, agree about the potential outcomes related to on-demand ridehailing and sustainable transportation goals? What are stakeholder perspectives on the policies and strategies that might facilitate emerging on-demand transportation services to most effectively enhance sustainability and mobility outcomes? What decision making venues and approaches are supported by different stakeholders in the process, and how can these approaches be pursued in order to realize policy goals related to sustainability of on-demand ridehailing? I.e., what venues, and at what level can most effective policies be introduced to facilitate sustainability improvements in transportation by embracing on-demand ridehailing services.To answer these questions, a series of interviews were completed with stakeholders from California Metropolitan Planning Organizations (MPOs) and Regional Transportation Planning Agencies (RTPAs), from state agencies, the ridehailing industry, and local planning agencies or transportation divisions of cities. The results of this study indicate that policy makers must consider the varied systems and contexts throughout the state; and likely throughout the US. Further, there is an existing dialogue on these topics among transportation professionals, public interest groups, academics and policy makers. In this study, the researchers took a systematic approach to documenting this dialogue and identifying meaningful messages and policy guidance that is not possible without a rigorous scientific approach.View the NCST Project Webpage