High Mileage Research Articles

Comparison of high mileage LPG cars in different technical condition in Czechia: Particle-bound PAHs

Liquefied petroleum gas (LPG) is represented in the literature as a transport fuel with lower regulated and non-regulated emissions compared to petrol. For the purpose of this paper, real-world emissions measurements were performed on a random sample of four commonly operated passenger vehicles with higher mileage (over 200 thousand km) and on a new one. The aim is to compare the emission factors of particle-bound polycyclic aromatic hydrocarbons (PAHs) in dual-fuelled passenger cars running on LPG and petrol, or rather to compare the emission factors of the two fuel types. PAH concentrations are determined by gas chromatography based on the analysis of particles captured on a filter during isokinetic sampling of the exhaust gas during driving in real traffic. In terms of the sum of the 8 most hazardous PAHs analysed, LPG fuelling reduced the total (summary) emission factor of only two of the vehicles analysed, by 22% and 26% respectively compared to petrol. For the remaining vehicles, there was an increase in the total emission factor ranging from 4.4 to 68.8%. The results show that in terms of particle-bound PAHs, the benefit of LPG fuel in terms of vehicle emissions may not be so clear-cut in real-world tests and it depends very much on whether a suitable propulsion system is fitted to the vehicle, how it is set up and how the vehicle is serviced (i.e. the vehicle overall condition).

Reliability Improvement in the Traction System of Tanzania Standard Gauge Railway

In recent years, many African governments have been developing Standard Gauge Railway (SGR) to replace the old after becoming absolute, inefficient Meter Gauge System (MGR) to carry more loads at high mileage and speed while combating the oil and environmental crises. With the increase of SGR, the amount of traction systems has grown sharply, the service life of the traction system has increased gradually, and the components of the vehicle traction system have become worn and aged as a result. While Tanzania is transitioning to SGR with its gradually increasing traction systems, reliability improvement becomes a key for the sustainability of its high-speed train services. This paper, therefore, aims to improve the reliability of traction motors used in Tanzania’s SGR. Firstly, the factors affecting the reliability of the traction system of Tanzania’s SGR and their significance are evaluated. Secondly, the computerized maintenance management system (CMMS) is designed to streamline and automate the maintenance management processes of the traction system of Tanzania’s SGR. Finally, a regression model is established to forecast the uptime based on the established factors. The obtained uptime hours were predicted in order to compute the reliability of the traction motor and its criticality in operation. Critical factors for improving reliability have also been highlighted. These findings play vital roles in establishing the fundamentals of factors that affect reliability as well as strategies and countermeasures to extend the operational life of the traction motors cost-effectively.

Bio-Based Pyrrole Compounds Containing Sulfur Atoms as Coupling Agents of Carbon Black with Unsaturated Elastomers.

In this work, the hysteresis of elastomer composites suitable for tire compounds was reduced by using CB functionalized with pyrrole compounds containing sulfur-based functional groups reactive with the elastomer chains. CB was functionalized with bio-based pyrrole compounds: 2-(2,5-dimethyl-1H-pyrrol-1-yl)ethane-1-thiol (SHP) and 1,2-bis(2-(2,5-dimethyl-1H-pyr-rol-1-yl)ethyl)disulfide (SSP), bearing an -SH and an -SS- functional group, respectively. SHP and SSP were synthesized via a one-pot two-step synthesis, with yields higher than 70%, starting from biosourced chemicals as follows: 2,5-hexanedione from 2,5-dimethylfuran, cysteine and cysteamine. The functionalization of CB was carried out by mixing the CB with PyC and heating, with quantitative yields ranging from 92 to 97%. Thus, the whole functionalization process was characterized by a high carbon efficiency. The formation of the covalent bond between SHP, SSP and CB, in line with the prior art of such a functionalization technology, was proven by means of extraction and TGA analyses. The reactivity of the sulfur-based functional groups with unsaturated polymer chains was demonstrated by using squalene as the model compound. Poly(styrene-co-butadiene) from solution anionic polymerization and poly(1,4-cis-isoprene) from Hevea Brasiliensis were the elastomers employed for the preparation of the composites, which were crosslinked with a sulfur-based system. Pristine CB was partially replaced with CB/SHP (33%) and CB/SSP (33% and 66%). The PyC resulted in better curing efficiency, an increase in the dynamic rigidity of approximately 20% and a reduction in the hysteresis of approximately 10% at 70 °C, as well as similar/better ultimate tensile properties. The best results were achieved with a 66% replacement of CB with CB/SSP. This new family of reactive carbon blacks paves the way for a new generation of 'green tires', reinforced by a CB reactive with the polymer chains, which provides high mechanical properties and low rolling resistance. Such a reactive CB eliminates the use of silica, and thus the ethanol emission resulting from the condensation of silane is used as a coupling agent. In addition, CB-based tires are characterized by a higher mileage, at a moment in which the reduction in tire wear has become a primary concern.

Developing a low-carbon hybrid of ammonia fuel cell and internal combustion engine for carbon neutrality

With global warming and an increase in extreme weather, reducing carbon emissions in response to climate change has become a global consensus. Compared with traditional fuel vehicles, hybrid vehicles have the benefits of energy savings, low grid-load, and low emissions. The hybrid vehicles use the internal combustion engine and lithium-ion batteries as the hybrid power source to achieve the best match between the engine and the motor. However, the current commercial hybrid vehicle still has such defects as high dependence on fossil fuels, high carbon emissions, poor safety, etc. As such, it is necessary to explore and develop the next generation low-carbon hybrid vehicles. Herein, we propose a new-type hybrid of ammonia fuel cell and internal combustion engine with high-energy conversion efficiency and low-carbon emissions. Considering the advantages of low-carbon emissions, high mileage, fast refueling, low-cost, high-energy conversion efficiency, and high safety, a green low-carbon concept of the ammonia fuel cell-internal combustion engine hybrid vehicle (AFC-ICE HV) is proposed. This will help improve the scale and efficiency of China's green energy conversion, establish a green, low-carbon and sustainable economic system, provide new impetus for tackling climate change and environmental protection recovery, and help China and the world to achieve the Carbon Peak and Carbon Neutrality goal.

How do young people move around in urban spaces?: Exploring trip patterns of generation-Z in urban areas by examining travel histories on Google Maps Timeline

Generation Zs have become dominant in the urban areas of various metropolitan cities worldwide, including in developing countries such as Indonesia. Their number has been estimated to be more than one-quarter of the population, and it is expected that they will become the largest generation in the coming years. Their contribution to the number of trips in urban areas has been significant, making it important to examine their travel patterns. The aim of this study had been to investigate the travel patterns of Generation Zs in the urban areas of developing countries such as Indonesia, where public transportation systems are not yet adequate and urban mobility is dominated by private vehicles (motorcycles and cars). This study had explored the travel behavior of Generation Zs, specifically their trip chains and mileage. This study had attempted to fill the research gap in travel pattern analysis using a travel diary approach, which is usually conducted over a relatively short period. Typically, a travel diary survey is only conducted over a few days or weeks since the approach requires significant time and is costly, while it is also susceptible to reporting and transcription errors. By utilizing travel history data from Google Maps Timeline, this study had observed the movement history of 434 Generation-Z individuals aged 17–24 years for 153 days (from August to December 2022). This approach is considered an alternative or complement to the travel diary survey, which had been commonly used. In the analysis, we had also considered gender, financial ability, home location, and workplace or campus location to discover how many trips had been made and how far people had traveled for their daily activities, both on weekdays and weekends. There had been a total of 213,094 trips observed, 63% of which had been made by motorcycle, and 35% of which had been made by car. (The remainder had been via walking, cycling, and public transportation, at only 2% overall.) The results had shown that men had made more daily trip chains and had had higher mileage than women, both on weekdays and weekends. Overall, the number of daily trips made on weekdays had been higher than on weekends. However, the research had also found that the higher the financial ability of the Generation-Z individual, the more daily trips they had made, especially on weekends. Even those with financial ability above IDR 2.4 million (>USD 156.37) had made more daily trips on weekends than on weekdays. The regression analysis results had shown that gender and financial ability had significantly influenced daily trips and mileage. Home location and workplace or campus location had also impacted daily trips and mileage. In addition, the results of this study also fill the gap in previous research on the travel behavior of Generation Z. With the characteristics of the built environment that still lack adequate public transportation systems and the dominance of private vehicles in urban mobility, the research findings show significant differences with developed countries that already have adequate public transportation systems.

Ceramic Fillers for Improved Lithium-Sulfur Batteries

With the decarbonization of transportation, the demand for electric vehicles (EVs) and batteries that can power these EVs has been increasing. Lithium-ion-based batteries are already well-established and are considered the main chemistries to power current EVs. However, limited specific energy (< 300 Wh/kg) prevents these batteries from having high mileage vehicles. Lithium-sulfur batteries are considered the most promising next-generation energy storage system as they high theoretical capacity (~1675 mAhg-1), low cathode materials cost, and cell energy densities that can exceed 700 Wh/kg [1,2]. However, some major drawbacks prevent the Li-S battery system from being applicable in energy devices and hinder its commercialization, that include low power density and rapid capacity degradation during their cycling life. In addition, the lithium metal anode in Li-S batteries bring various issues to the forefront such as continuous solid electrolyte interface growth, dendrite formation, and loss of active lithium and electrolyte. These issues are further exacerbated at high C-rates which increases the possibility of an internal short-circuit and sudden cell failure [3]. In order to promote longer life cycles and prevent sudden cell failure, a thorough understanding of the cell’s electrochemical behavior is crucial for the development of a stable and practical Li-S battery system. The introduction of oxide fillers such TiO2, Al2O3, SiO2, etc. has been previously studied in various lithium-ion systems and has been shown to improve the cell’s lithium-ion transport properties, which in turn improve the performance of Li-S cells [4]. When used as interlayers they can also trap soluble polysulfides diffusing out of the cathode and reduce their crossover to the anode which helps reduce the shuttle effect of said polysulfides.In the present study, the use of a polysulfide immobilizing system to reduce sulfur loss and improve capacity retention has been demonstrated. The galvanostatic charge-discharge cycling study shows that cells retain higher capacity during the course of cycling. The initial capacity for Li-S cells with the filler average 1300+ mAh/g (C/10) while the capacity stabilizes around 1000 mAh/g after 3 cycles (C/5). The capacity retention at C/5 after 75 cycles was approximately 875 mAh/g which represents a rate 0.17% drop per cycle. When compared to control cells, the cells containing no fillers had lower initial capacity that averaged 1050 mAh/g and that rapidly declined to stabilize around 650 mAh/g. However, after this major drop, the cells remained stable no with measurable drop after 75 cycles. The behavior indicates that the cells with fillers delayed the effect of sulfur loss experienced in cells without fillers; however, the slow capacity drop that ensued, indicates that while polysulfide trapping was efficient it was unable to fully prevent it. The effect of fillers on the Coulombic efficiency (CE) also supports the polysulfide “trapping” mechanism and shows the ability of the cell to reduce the shuttle effect that contributes to lower CE values. Further electrochemical studies have been performed to understand the mechanisms of the improvement of the cell.

Optimization of Power-System Parameters and Energy-Management Strategy Research on Hybrid Heavy-Duty Trucks

Hybrid heavy-duty trucks have attracted wide attention due to their excellent fuel economy and high mileage. For power-split hybrid heavy-duty trucks, the optimization of powertrain parameters is closely related to the control strategies of hybrid vehicles. In particular, the parameters of the powertrain system will directly affect the control of the vehicles’ power performance and economy. However, currently, research on hybrid heavy-duty trucks employing power-split configurations is lacking. Furthermore, few studies consider both the optimization of powertrain parameters and the control strategy at the same time to carry out comprehensive optimization research. In order to address these issues, this paper focuses on the fuel economy of hybrid heavy-duty trucks with power-split configurations. Improved particle swarm optimization (IPSO) and dynamic programming (DP) algorithms are introduced to optimize powertrain parameters. With these methods being applied, hybrid heavy-duty trucks show a 2.15% improvement in fuel consumption compared to that of the previous optimization. Moreover, based on the optimal powertrain parameters, a DP-based rule-control strategy (DP-RCS) and optimal DP-RCS scheme are presented and used in this paper to conduct our research. Simulation results show that the optimal DP-RCS reduces fuel consumption per hundred kilometers by 11.35% compared to the rule-based control strategy (RCS), demonstrating that the combination of powertrain parameter optimization and DP-RCS effectively improves the fuel economy of hybrid heavy-duty trucks.

A Study on the Optimization of the Louver Fin Heat Exchanger for Fuel Cell Electric Vehicle Using Genetic Algorithm

Fuel cell electric vehicles offer a short fuel charging time and high mileage, but require precise thermal management technology to ensure the durability and efficiency of the stack. Accordingly, the size and weight of the heat exchanger increase to ensure the performance of the heat exchanger. For this reason, a louver fin type heat exchanger requires optimal size and weight, as well as high performance. This paper optimally designs high-performance heat exchangers with reduced size and weight by applying genetic algorithms to solve this problem. The optimal result value was achieved by optimizing the design variables using concentrated variable modeling and a genetic algorithm, and the dynamic characteristics of the heat exchanger were analyzed by applying the driving cycle of the vehicle. In addition, 3D modeling was conducted to present the weight and practically applicable form. As a result, compared to the existing model, the heat transfer rate and effectiveness were improved by 5% and 1.6%, respectively, and the weight was also reduced by 5.8%. These results exceed the expected performance improvements of low size and weight. Moreover, it is expected that an improved heat exchanger optimization, as well as a design reflecting a drive cycle, could be conducted using the proposed genetic algorithm and be applied not only to a heat exchanger, but also to various components.

Research of Car Cooler Thermal Performance Depending on the Mileage of Cooler and Coolant

The effect of car cooler mileage and coolant mileage on cooler thermal performance was experimentally investigated. The water–ethylene-glycol-based coolant with mileages of 0 km, 50,000 km, and 100,000 km was circulated in new and used car coolers with mileages of 0 km and 100,000 km, respectively. The heating and cooling time of coolants, heat transfer rate, and thermal performance were evaluated. The coolant with a mileage of 0 km in the new cooler achieved a heating time of 41 min and 30 s, which is 8 min less time compared to the coolant with mileage of 100,000 km in the used cooler. When the operating temperature was reached earlier, the engine ran more efficiently and consumed less fuel. The coolant with 0 km mileage in the new cooler achieved a cooling time of 4 min and 30 s, which is 3 min and 30 s less time compared to the coolant with 50,000 km mileage in the new cooler. The new coolant in the new cooler achieved the shortest heating time and cooling time and the highest thermal performance (η = 0.79). The used cooler with the new coolant only achieved a one-time decrease compared to the new cooler and new coolant. The coolant with 50,000 km and 100,000 km mileage for the new cooler and used cooler reached a drop of 1.01 to 1.02 times compared to the new cooler. Coolant and coolers with higher mileage have no significant effect on the thermal performance of the cooler and the correct cooling function of the car engine.

Experimental Evaluation of the Effect of Replacing Diesel Fuel by CNG on the Emission of Harmful Exhaust Gas Components and Emission Changes in a Dual-Fuel Engine

The constant development of civilization increases environmental pollution as a result of industrial activity and transport. Consequently, human activity in this area is restricted by regulations governing the permissible emission of harmful substance components into the environment. These include substances emitted by combustion engines, the use of which remains high in many industries. Consequently, research is being conducted to reduce the emissions of harmful exhaust components from existing and newly manufactured internal combustion engines. This research presents a used semi-truck engine, in which an innovative Compressed Natural Gas (CNG) supply system was applied. Using this fuel supply installation allows a mass exchange of the base diesel fuel to natural gas of up to 90%. The study evaluated the effect of the diesel/CNG exchange ratio for different engine operating conditions (engine load, speed) on the concentration of toxic components, such as CO, NO, NO2, NOX, as a sum of NO, NO2, CH4, C2H4, C2H6, C3H8, NH3, and CH2O. The use of a dual-fuel system had a positive effect on the emissions of some harmful exhaust components, even in an engine from a vehicle that had been running for many years on diesel and at high mileage, but, simultaneously, the emissions of some harmful exhaust gas components increased.

Energy Losses Related to Ring Pack Wear in Gasoline Car Engine

Decreasing production and rising prices of cars, especially those with electric drive, lead to longer use of cars with internal combustion engines. It can be assumed that in the future, more and more cars powered by such engines with high mileage and therefore high wear will be used. Engine wear leads to reduced efficiency and increased emissions. This paper analyzes the impact of wear of the piston–rings–cylinder system components on energy losses associated with gas leakage from the combustion chamber and friction of the rings against the cylinder liner in a car spark-ignition engine. A ring pack model was used for the analyses. The input data for the simulation were gained in measurements made on the engine test stand and measurements of the wear of the engine components used in the car. The energy losses associated with blow-by in an unworn engine ranged from 1.5% of the indicated work at high load to almost 5% at low load. In the engine after 300,000 km, these losses increased to 2.5% and 7.5%, respectively. Ring friction losses in an unworn engine ranged from 1.5% at high load to 9% at low load. The effect of wear on these losses was smaller. They increased by only 0.1% at high load and 1% at low load.

Ultrafine-Grained Ni-Rich Layered Cathode for High-Performance Li-Ion Batteries

Currently, Li-ion batteries (LIBs) are the main power source for electric vehicles (EVs) because of their high energy density, excellent rate performance, and long cycle life. However, even EVs that are powered by state-of-the-art LIBs are unable to meet the driving range offered by internal combustion engine vehicles (ICEVs), which is typically 600–800 km.1 The properties of LIBs are strongly related to the nature of positive electrodes (cathodes), and thus, the selection of appropriate cathodes is of paramount importance. Currently, Ni-rich layered LiMO2 (M = Ni, Co, Mn, and/or Al) compounds are considered ideal cathode materials for EV batteries because their high capacity enables EVs to achieve high mileage per charge. Although Ni-rich layered cathodes are advantageous in terms of energy density and material cost, in general, they have considerably decreased cycling lifetimes with inferior thermal stabilities, which hinder their commercialization. The inherent structural instability of Ni-enriched layered oxide cathodes, particularly in the deeply charged state, leads to a build-up of mechanical strain.2 The strain build-up causes the nucleation and propagation of microcracks, which enable electrolyte infiltration and accelerate structural deterioration, which has plagued attempts to stabilize the cycling performance of Ni-rich layered cathodes.3 In this study, we demonstrate that limiting the primary particle size of the cathode resolves the capacity fading problem as nano-sized primary particles effectively relieve the high internal strain associated with the phase transition near charge end and fracture-toughen the cathode. Particle size refinement, achieved by inhibiting the grain growth during lithiation through the introduction of a high-valence dopant, imparts the necessary mechanical toughness to counter the high internal strain associated with the phase transition near charge end. The Li[Ni0.95Co0.04Mn0.01]O2 cathode, whose microstructure is engineered to mitigate the mechanical instability of Ni-rich layered cathodes, represents a next-generation, high energy-density cathode with a long cycle life and fast charging capability. Reference s : [1] K. B. Naceur, Tracking Clean Energy Progress (International Energy Agency, 2016).[2] H.-H. Ryu, K.-J. Park, C. S. Yoon and Y.-K. Sun, Chem. Mater. 30 (2018) 1155–1163.[3] G. W. Nam, N.-Y. Park, K.-J. Park, J. Yang, J. Liu, C. S. Yoon, Y.-K. Sun, ACS Energy Lett. 4 (2019) 2995–3001.

The impacts from cold start and road grade on real-world emissions and fuel consumption of gasoline, diesel and hybrid-electric light-duty passenger vehicles

Progressively stringent regulations regarding vehicle emissions and fuel economy have spurred technology diversification in light-duty passenger vehicles (LDPVs). To assess the real-world emissions and fuel economy performances of hybrid electric vehicles (HEVs) compared to conventional internal combustion engine (ICE) vehicles, on-road measurements of ten gasoline, four diesel and six full hybrid LDPVs were performed using portable emissions measurement systems (PEMS) in Macao, China. The hot-running emission results indicate that the high emission risks of gasoline vehicles are associated with high mileage and old model years. Diesel vehicles are found to be the highest pollutant emitters in this study due to the intentional removal of aftertreatment systems. Under hot-running conditions, HEVs, as expected, could achieve carbon-reduction benefits of approximately 30 % (i.e., lower CO2 emissions and fuel consumption) compared to their conventional gasoline counterparts, while no measurable reduction in pollutant emissions was observed except in NOX (~70 % reduction). In contrast, the cold-start extra emissions (CSEEs) of CO2 reached 120–364 g/start for these HEVs, even exceeding the maximum values of conventional gasoline vehicles. However, the higher CO2 CSEEs of HEVs can be far offset by their hot-running emission reduction benefits. For tailpipe pollutants, the CSEEs of the HEVs were reduced by 21 %–68 % on average in comparison to those of conventional gasoline vehicles. Furthermore, strong correlations (R2 values of 0.69–0.89) between the road grades and relative emissions were observed. These results can provide necessary information regarding the improvement of future LDPV emission models and inventories.

A transferable energy management strategy for hybrid electric vehicles via dueling deep deterministic policy gradient

Due to the high mileage and heavy load capabilities of hybrid electric vehicles (HEVs), energy management becomes crucial in improving energy efficiency. To avoid the over-dependence on the hard-crafted models, deep reinforcement learning (DRL) is utilized to learn more precise energy management strategies (EMSs), but cannot generalize well to different driving situations in most cases. When driving cycles are changed, the neural network needs to be retrained, which is a time-consuming and laborious task. A more efficient transferable way is to combine DRL algorithms with transfer learning, which can utilize the knowledge of the driving cycles in other new driving situations, leading to better initial performance and a faster training process to convergence. In this paper, we propose a novel transferable EMS by incorporating the DRL method and dueling network architecture for HEVs. Simulation results indicate that the proposed method can generalize well to new driving cycles, with comparably initial performance and faster convergence in the training process.

Monitoring of oil lubrication limits, fuel consumption, and excess CO2 production on civilian vehicles in Mexico

The vehicle fleet in some regions of the world continues to age, so it is difficult to reduce the consumption of fuels, meet environmental objectives and mitigate the cost it represents. Studies exist regarding low mileage vehicles, yet it is important to know the effect generated by high mileage vehicles, which represents a higher percentage in the word. This work was based on the oil degradation. A maximum value of decrease in viscosity of 31% was found, from which the lubrication efficiency of the oil decreases. This also leads to a significant increase in gCO2/km and fuel consumption. In a deeper analysis of the Nissan Tsuru, we found an annual excess of 69.25 Lt of fuel consumption that produces 129.024 Kg additional of CO2 (12.18gCO2/km) with a cost of $1,414.08 Mexican pesos. Due to the average vehicle age in Mexico (15.3 years), these results can be taken as an average for the 45 million plus cars that are currently in circulation. Also, 5.806 million tons of CO2 are generated that represent 3.6% of all current emissions. This leads to a consumption of 3.11 billion liters of fuel at a cost of $63.63 billion Mexican pesos. This methodology can be generalized for different brands of cars and oils in countries with a vehicle fleet similar, in search of improving the monitoring and proper use of automotive oil. In addition, this provides information on the negative effects, so that the countries can establish procedures and strategies for compliance with low pollution policies.

Enhancing circularity in the car sharing industry: Reverse supply chain network design optimisation for reusable car frames

The transportation sector is a great contributor of global carbon emissions, thus technical, regulatory, and behavioural efforts are being made to move towards more sustainable mobility, reducing the sector's environmental impact. Among the proposed solutions, car sharing is an appealing alternative for both environmental and societal reasons. However, society is facing another challenge with the rapid increase of vehicles that have reached the end of their life. As a result, regulatory initiatives drive car manufacturers towards a circular economy paradigm that incorporates reuse, remanufacturing and recycling processes in their supply chains. This work proposes and optimises the design of a reverse supply chain that enables circular economy pathways for the automotive sector with particular focus on car sharing vehicles' components that are reusable. Car sharing vehicles are selected due to their high mileage, short service life and rapidly increasing demand. This is the first work that identifies optimal reverse supply chains for reusable car sharing vehicle parts. The particular investigated case study involves a reusable and remanufacturable carbon fiber reinforced polymer car frame, which is selected due to its long-life span and light weight properties. The results indicate that the per unit and overall system cost is minimised when the percentage of frames remanufactured increases, thus efforts are required regarding the design of frames with remanufacturability in mind. The impact of economies of scale in cost reduction is demonstrated. Finally, the reusable frame appears to be advantageous compared to the single use one both environmentally and economically. • Car sharing: promising solution both for environmental and societal benefits • Economic optimisation of the reusable car frame reverse supply chain design • Carbon fiber car body parts due to long life span and lightweight properties • Location optimisation of new entities of repair/remanufacturing facilities • Shift to frames designed robustly and with remanufacturability in mind

Experimental Assessment of the Impact of Replacing Diesel Fuel with CNG on the Concentration of Harmful Substances in Exhaust Gases in a Dual Fuel Diesel Engine

The problem of global warming and related climate change, as well as rising oil prices, is driving the implementation of ideas that not only reduce the consumption of liquid fuels, but also reduce greenhouse gas emissions. One of them is the use of natural gas as an energy source. It is a hydrocarbon fuel with properties allowing the reduction of CO2 emissions during its combustion. Therefore, solutions are being implemented that allow natural gas to be supplied to means of transport, which are trucks of various categories and purposes. This article presents the results of tests of an engine from a used semi-truck, to which an innovative compressed natural gas (CNG) supply system was installed. This installation (both hardware and software), depending on the engine operating conditions, enables mass replacement by natural gas (up to 90%) of the basic fuel—diesel oil. During the tests, on the basis of the obtained results, the influence of the diesel fuel/CNG exchange ratio under various engine operating conditions on the concentration of toxic CO2, CO, NO, NO2, CH4, C2H6, NMHC, NH3 and exhaust smoke was assessed. The test results confirm that, compared to conventional fueling, the diesel/CNG-fueled engine allows for a significant reduction in CO2 concentration even in a car operated for several years with diesel fuel and with high mileage. The use of a non-factory installation significantly increased the concentration of methane CH4, nitrogen dioxide NO2 and carbon monoxide CO in the exhaust gas. It was found that the smoke content and the temperature of exhaust gases did not decrease with increasing ratio of fuel replacement. The concentration of CO, NOX, CH4 and NMHC was increased, while the concentration of CO2, C2H6, NH3 and the consumption of diesel fuel by the engine, decreased significantly. The innovation of the research is based on the use of a modern and unique engine gas fuel system control system where the original fuel supply system with unit pumps is able to reduce diesel oil consumption by up to 90%.

Dietary-Lifestyle Patterns Associated with Bone Turnover Markers, and Bone Mineral Density in Adult Male Distance Amateur Runners-A Cross-Sectional Study.

Background: Excessive mileage can be detrimental to bone mineral density among long-distance runners. The negative effects of mileage could be alleviated by appropriate nutrition. The purpose of this study was to analyse the dietary-lifestyle patterns in relation to bone mineral density and bone turnover markers among amateur marathoners. Methods: A total of 53 amateur male distance runners were divided into two clusters by k-means cluster analysis. Bone mineral density was measured by dual X-ray absorptiometry (DXA). Blood was drawn to analyse bone resorption marker C-terminal telopeptide (cTX) and bone formation marker amino-terminal propeptide of type I collagen (PINP). Food frequency intake and lifestyle information were measured by multicomponent questionnaire KomPAN®. Yearly average mileage per month was taken from each participant. Results: There were two distinguished clusters: Less-healthy-more-active-low-Z-score (LessHA) (n = 33) and More-healthy-less-active-high-Z-score (MoreHLA) (n = 20). LessHA had a lower frequency intake of pro-healthy food groups, a lower number of meals during a typical day, and a higher mileage training than the group of athletes who followed the MoreHLA. Athletes following the LessHA pattern also had a lower Z-score in the lumbar spine and femoral bone and a lower PINP. Conclusion: The current study suggests that pro-healthy dietary patterns and lower mileage may favour higher bone mineral density in male amateur marathoners.

Energy and greenhouse gas implications of shared automated electric vehicles

Automated vehicles can facilitate vehicle sharing within and between households, thus decreasing ownership rates, albeit increasing miles travelled. While electrification can achieve deep reductions in transportation-related greenhouse gas emissions, shared automated electric vehicles will have different charging needs considering their higher mileage. In this study, travel survey data collected in Toronto is used to optimize the charging needs of shared automated electric vehicles, with the objective of reducing greenhouse gas emissions from electricity generation by choosing charging times that are associated with lower marginal emission factors. Optimized charging schedules reduce greenhouse gas emissions by at least 50% relative to vehicles charging once they return home. Life cycle assessment of multiple sharing scenarios indicates that higher levels of sharing increase emissions. Indeed, empty mileage associated with vehicle relocation and higher deterioration lead to a higher fleet turnover. With vehicle sharing, there is a risk of increasing mileage and vehicle production emissions.

Gasoline Direct Injector Deposits: Impacts of Fouling Mechanism on Composition and Performance

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;Injector performance in gasoline Direct-Injection Spark-Ignition (DISI) engines is a key focus in the automotive industry as the vehicle parc transitions from Port Fuel Injected (PFI) to DISI engine technology. DISI injector deposits, which may impact the fuel delivery process in the engine, sometimes accumulate over longer time periods and greater vehicle mileages than traditional combustion chamber deposits (CCD). These higher mileages and longer timeframes make the evaluation of these deposits in a laboratory setting more challenging due to the extended test durations necessary to achieve representative in-use levels of fouling. The need to generate injector tip deposits for research purposes begs the questions, can an artificial fouling agent to speed deposit accumulation be used, and does this result in deposits similar to those formed naturally by market fuels?&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;In this study, a collection of DISI injectors with different types of conditioning, ranging from controlled engine-stand tests with market or profould fuels, to vehicle tests run over drive cycles, to uncontrolled field use, were analyzed to understand the characteristics of their injector tip deposits and their functional impacts. The DISI injectors, both naturally and profouled, were holistically evaluated for their spray performance, deposit composition, and deposit morphology relative to one another. The testing and accompanying analysis reveals both similarities and differences among naturally fouled, fouled through long time periods with market fuel, and profouled injectors, fouled artificially through the use of a sulfur dopant. Profouled injectors were chemically distinct from naturally fouled injectors, and found to contain higher levels of sulfur dioxide. Also, profouled injectors exhibited greater volumes of deposits on the face of the injector tip. However, functionally, both naturally-fouled and profouled injectors featured similar impacts on their spray performance relative to clean injectors, with the fouled injector spray plumes remaining narrower, limiting plume-to-plume interactions, and altering the liquid-spray penetration dynamics, insights from which can guide future research into injector tip deposits.&lt;/div&gt;&lt;/div&gt;