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A numerical study was created and developed to evaluate the engine performance, combustion characteristics and exhaust gas emissions of a spark-ignition engine by using gasoline, liquefied petroleum gas (LPG) and ethanol fuels at different cylinder head temperature (150, 200, 250, 300 and 350 C) at engine speed 2500 rpm (revolution per mint) and constant engine load. Four-cylinder four-stroke, water cooling system spark ignition engine was used in this study. The results were collected and appear that the brake power and effective torque were decreased when the cylinder head temperature increased, whereas there is no noted alteration in brake specific fuel consumption for all tested fuels. The peak fire pressure reductions while the peak fire temperature slightly growths when transfer from low to higher cylinder head temperatures. LPG and ethanol produced lower brake power and effective power

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Alternative fuels are a fun renewable resource that can help minimize particle pollution from internal combustion engines. At a constant engine speed of 2500 rpm, a comparative numerical analysis was undertaken to analyze the impacts of four alternative fuels (ethanol, hydrogen, gasoline, and liquefied petroleum gas (LPG)) on exhaust gas emissions. Carbon monoxide, nitrogen oxide, and unburned hydrocarbons are all monitored as exhaust gases. According to this study, using fuels including ethanol and hydrogen can significantly reduce emissions. With hydrogen, the majority of hazardous contaminants in exhaust gas are significantly decreased. In comparison to gasoline, hydrogen contains relatively clean unburned hydrocarbons. Ethanol and hydrogen are clean fuels that do not contribute to increase in net emissions from engines. The findings showed that ethanol fuel emits less carbon monoxide than regular gasoline, but LPG emits more CO. Furthermore, ethanol fuel burns cleaner and produces less CO than gasoline. In comparison to LPG fuel engines, NOx emissions were greater for gasoline fuel engines. Nonetheless, ethanol-fueled engines created less NOx than gasoline-fueled engines. When working in lean conditions, the NOx emission of the hydrogen-fueled engine was about ten times lower than that of a gasoline-fueled engine. The studies also demonstrated that hydrogen fuel engines emit less HC pollution than gasoline fuel engines, but gasoline fuel engines emit more than ethanol fuel engines.

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The influence of different ignition timings and compression ratios on the combustion characteristics and performance of a gasoline direct injection GDI engine operating on gasoline and liquefied petroleum gas (LPG) fuels at a constant speed of 3000 rpm were numerically investigated. For this reason, a model was created and developed using the AVL Boost program (fully integrated IC engine simulation software). The results of this study showed that the effective power and effective torque were decreased for engines fueled with LPG compared to those of gasoline for all selected ignition timings. Also, brake specific fuel consumption was higher for LPG fuel than for gasoline fuel, but brake mean effective pressure, maximum cylinder pressure, and maximum cylinder temperature were higher for gasoline fuel than for LPG fuel. Increasing the compression ratios resulted in an increase in the effective power, effective torque, brake mean effective pressure, peak cylinder pressure, and peak cylinder temperature, but it also resulted in a decrease in the specific fuel consumption for both fuels.

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In the present work, the direct-injection petrol engine (GDI) combustion, emissions and performance at different engine speeds (1500, 2000, 2500 and 3000 rpm) with a constant throttle position have been studied. The fuel considered in this work is liquid petroleum gas (LPG) and gasoline. The software adopted in all simulations by the AVL BOOST 2016. A Hyundai 2.0 liter, 16 valves and 4 cylinders engine with a compression ratio 17.5: 1 is used. The effect of several inlet air temperatures (0, 10, 20, 30, 40 and 50 oC) on the engine performance, combustion and emissions are also studied. The results show that the increase in the inlet air temperature leading to increase the peak fire temperature, brake specific fuel consumption (BSFC) and nitrogen oxide (NOx). However, this process results in a reduction in the peak fire pressure, combustion period (duration), brake power and brake torque. The maximum fire temperature and maximum specific fuel consumption can be achieved when the engine speed is 3000 rpm and the inlet air temperature is 50 ºC.

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A numerical approach has been designed and modified with Advanced Simulation Technologies Boost to examine the impact of the piston face temperature on the performance of the spark ignition engine, combustion characteristics and emissions when using liquefied petroleum gas (LPG) and petrol fuels at an engine speed of 2500 rpm with a constant throttle position. In this work, a four-cylinder four-stroke spark ignition engine was used. The results show that when the piston face temperature increased, the brake power and the effective torque were reduced. No alteration in the specific brake fuel consumption for both fuels selected at higher piston face temperature has been observed. The peak fire pressure decreases while the peak fire temperature grows slightly when moving from lower to higher temperatures on the piston face. Liquid petroleum gas produced lower effective power and an effective torque

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The compression characteristic of an (AL-4% CU) alloy reinforced with different particles (boron carbide, silicon carbide, and titanium carbide) was numerically studied. For this purpose, a model was performed using COMSOL Multiphysics 4.1. Hence, three samples were selected and reinforced with carbide particles equal to 20 microns' in diameter and then compared with that one not reinforced. An axial load of 20 Newton was applied for all samples from both sides. The results showed that the alloy (AL-4% CU) reinforced with boron carbide particles has the highest compressive resistance compared to the other reinforced particles. The elongation of boron carbide, silicon carbide and titanium carbide particles were 1x10− 7 mm,(1.3* 10− 7 mm) and (1.5* 10− 7 mm) respectively, while it was (5.5* 10− 8 mm) for not unreinforced particles.

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In this article, the effect of adding a double gasket to cylinder head on combustion characteristics, performance and exhaust gas emissions of gasoline direct injection GDI engine was numerically investigated by utilizing the BOOST program. The study was carried out at different engine speed (1000 rpm to 3500 rpm, with increment 500 rpm) in a constant engine load fueled with gasoline fuel. The Vibe two-zone and Woschni 1990 models were selected as sub-model to calculated the combustion and heat transfer. The numerical results showed that the engine with a double gasket produces lower effective power and lower effective torque while the brake-specific fuel consumption BSFC was higher compared to that of an engine with a single gasket (original). Regarding the exhaust gas emissions, the engine with a double gasket emitted lower NOx emissions, while the soot emission was higher than that of the engine

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In this research, a comparison between Soldering and Brazing welding of pure copper metal using a (Zn-Sn) alloy filler was numerically investigated. The welding operations on the eight pieces with dimension (30mm x 20mm x 2mm) were carried out used (Auto Desk Inventor program) to prepare four samples, while the simulation was conducted on these samples by utilized the (COMSOL Multiphysics 4.1 program) to investigate the heat distribution and tensile stress. The simulation study results showed that the thermal distribution of Soldering welding was less than that of the Brazing welding in the area between (40-60 mm) and the maximum temperature of Soldering welding in that region was (405 C), while the highest temperature for the Brazing welding in the same area reaches to (449 C). The total displacement of the Soldering welding was up to1. 9 x10-7 mm greater than that of the Brazing welding when

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The engine performance, combustion characteristics and exhaust gas emissions of a four-cylinder, four-stroke indirect injection spark ignition engine has been numerically investigated at constant engine speed and different ignition timings when using gasoline, ethanol and LPG fuels. For this purpose, a model has been suggested by using a two-zone burnt and unburnt gas for in-cylinder combustion. The experimental data related to the cylinder pressures have been carried out to validate the engine model. The optimal effective power and effective torque were shown at advanced crank angle degrees before the top dead center. It is observed that the brake specific fuel consumption decreases if the ignition timings increase. The ethanol fuel exhausted a minimum level of carbon monoxide, unburnt hydrocarbon and oxide nitrogen emissions when compared with the gasoline fuel at all operating conditions. LPG fuel produced promising good emission results than that obtains from gasoline fuel.

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A numerical study has been carried out to determine the combustion characteristics, engine performance and emissions of a spark ignition engine. In this work, a fourcylinder, four-stroke indirect injection engine fueled with gasoline, LPG and ethanol was used. The results were collected at a constant engine speed of 2500 rpm with variable compression ratios of 8.5: 1, 10.5: 1, 12.5: 1 (original), 14.5: 1 and 16.5: 1. Calculations focused on how the parameter of compression ratio could affect variables such as emissions, peak fire temperature, peak fire pressure, specific fuel consumption, effective torque, and brake power. In the findings, it was established that under various compression ratios, LPG and ethanol exhibit superior or better combustion and performance characteristics. It was established further that on all the selected compression ratios, when ethanol is used as the engine fuel, there tends to be a notable decrease in the emissions of unburned hydrocarbon, nitrogen oxide, and carbon monoxide.

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In recent years, reducing the exhaust gas emissions of internal combustion engines yet maintaining the same engine performance has become one of the most important challenges for automotive companies. Using clean energy, such as alternative fuels, could offer a promising solution for reducing air pollution. In the current work, a comparative study was carried out on the engine performance and exhaust gas emissions of a one cylinder, four stroke spark ignition engine using gasoline, ethanol and LPG fuels. For this reason, a model was proposed. The results were collected at various engine speeds (1500, 2000 and 2500 rpm). It was found that there was a slight variation in engine performance, while there was a marked difference in exhaust gas emissions between gasoline and the other selected fuels.

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Biodiesel could now be considered as an alternative fuel for compression ignition engines and it can be used directly or in blends with diesel without engine modification. Biodiesel is non-toxic, contains no aromatics is sulphur-free, biodegradable and an oxygenated and renewable fuel. In the present work, a numerical study was performed to determine the engine performance and exhaust gas emissions of a direct injection DI, four-cylinder, diesel engine by using pure diesel and biodiesel B15 fuel (15% sunflower oil mixed with 85% diesel, by volume) operating at different fuel injection timings. The results were acquired at engine speed 3000 rpm under full load conditions. A comparison between the numerical results and experimental data regarding the in-cylinder pressure was done in order to check the usefulness of this model. The results have shown that the engine performance of biodiesel B15 was slightly

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Controlled autoignition delay is considered a very promising new technology, having the potential of combining low fuel consumption with low pollutant emissions. In this study, the effect of pure diesel fuel and biodiesel B20 (20% rapeseed oil mixed with 80% diesel fuel, by volume) on ignition delay period, at different engine speeds, under full load operating conditions, has been investigated experimentally and numerically. For this purpose, two models were proposed. The experimental results were compared with the ignition delay predicted by some correlations and by the considered models. The results showed that the ignition delay period of biodiesel B20 is shorter than that of pure diesel fuel at similar operating conditions. Regarding pure diesel fuel, the ignition delay periods are in good accordance with Arrhenius type correlations, whereas for biodiesel B20 the correlation results are significantly different than the experimental data.

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The ignition delay period for a compression ignition engine fueled alternatively with pure diesel and with biodiesel B20 has been experimentally and numerically investigated. The engine was operated under full load conditions for two speeds, 1400 rpm speed for maximum brake torque and 2400 rpm speed for maximum brake power. Different parameters suggested as important to define the start of combustion have been considered before the acceptance of a certain evaluation technique of ignition delay. Correlations between these parameters were analyzed and concluded about the best method to identify the start of combustion. The experimental results were further compared with the ignition delay predicted by some correlations. The results showed that the determined ignition delays are in good agreement with those of the Arrhenius type expressions for pure diesel fuel, while for biodiesel B20 the correlation …

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An experimental and numerical study was performed to investigate the impact of Biodiesel B20 (blends 20% Rapeseed methyl ester with 80 % Diesel volumetric fraction) and different energetic fractions of hydrogen content (between 0 and 5%) on the mixture formation, combustion characteristics, engine performance and pollutant emissions formation. Experiments were carried out on a tractor Diesel engine, four-cylinders, four-stroke, 50 kW/2400 rpm, and direct injection. Simulations were conducted using the AVL codes (HYDSIM and BOOST 2013). Simulation results were validated against experimental data, by comparing the inline pressure, needle lift, in-cylinder pressure curves for Biodiesel B20 and pure Diesel fuels at 1400 rpm and 2400 rpm, respectively, under full load operating conditions. Good agreement with a maximum of 2.5% relative deviation on the peak results revealed that overall operation

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Biodiesel is one of the biodegradable and renewable fuels, which is originated from vegetable oil or animal fats. Rapeseed biodiesel is a kind of biofuel which is gaining acceptance in the market due to many ‎environmental and economic benefits. It can be used alone or in a blend with Diesel fuel, directly in compression ‎ignition engines, without any modifications. This review collects and analyzes published papers concerning the usage of rapeseed biodiesel as an alternative fuel in Diesel ‎engines. It covers engine combustion, ‎performance and emissions characteristics. Research results reveal that ‎rapeseed‎ biodiesel, ‏either pure or blended with Diesel, ‎‏has ‎lower ‎heat ‎release rate, reduced ignition delay, lower thermal efficiency and ‎higher brake ‎specific ‎fuel ‎consumption. Carbon monoxide (CO) and particulate matter (PM) exhaust emissions are up to 60% lower, while carbon dioxide (CO2) ‎and nitrogen oxides

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Biodiesel produced from rapeseed oil considered one of promising option in Romania for compression ignition engines due to the higher level of productions and environmental friendliness. In this work, biodiesel B20 is prepared from rapeseed oil (blends 20% Rapeseed methyl ester with 80 % Diesel volumetric fraction). The fuel is tested on a direct injection, four cylinders, four stroke Diesel engine at different engine speeds under full load operating condition. Parameters such as effective power, effective torque, brake specific fuel consumption, carbon monoxide, smoke and nitrogen oxides emissions (NOx) are evaluated. Results show that the engine effective power and torque does not change significantly with biodiesel B20. The brake specific fuel consumption increased with biodiesel B20 for all operating conditions. Carbon monoxide and smoke emissions are up to 60% lower, while the NOx emissions

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In the current study, the ignition delay period for a compression ignition engine fueled with Diesel and biodiesel B20 at engine speeds 1400 rpm and 2400 rpm under full load operating conditions has been experimentally identified. The experimental results of Diesel fuel are compared with the ignition delay predict by four known correlations, while the results of biodiesel B20 are compared with only one correlation. The results showed that the ignition delay period of biodiesel B20 is shorter than that produced from Diesel fuel at all operating conditions. The Assanis correlation is approximately reaching the experimental results for both speeds when using Diesel fuel. Regarding the biodiesel B20, the correlation results are significantly different than the experimental results at all operating conditions.

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Using diesel-biodiesel blends in Diesel engine has been highlighted to offer a good opportunity in reducing the exhaust emissions for particular engine operating conditions. The blended diesel-biodiesel with up to 20 % biodiesel in petroleum diesel fuel (B20) is in production and available for use in USA being considered as viable path to be followed in the effort to reduce the effect of the greenhouse gas emissions issued by the operation of heat engines. Although previous studies investigating the effect of B20 on engines emissions led to some contradictory results, the life cycle analysis performed on the well-to-wheel base shown that 35 % reductions of CO2 emission, in respect to fossil fuels operation are possible. The association of this alternative fuel use with some new combustion concepts as homogeneous charge compression ignition (HCCI) premixed charge compression ignition (PCCI) or partially

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This study proposes engine model to predicate the performance and exhaust gas emissions of a single cylinder four stroke direct injection engine which was fuelled with diesel and palm oil methyl ester of B7 (blends 7% palm oil methyl ester with 93% diesel by volume) and B10. The experiment was conducted at constant engine speed of 3000 rpm and different engine loads operations with compression ratios of 18: 1, 20: 1 and 22: 1. The influence of the compression ratio and fuel typeson specific fuel consumption and brake thermal efficiency has been investigated and presented. The optimum compression ratio which yields better performance has been identified. The result from the present work confirms that biodiesel resulting from palm oil methyl ester could represent a superior alternative to diesel fuel when the engine operates with variable compression ratios. The blends, when used as fuel