The Experts below are selected from a list of 120297 Experts worldwide ranked by ideXlab platform
K H Reddy - One of the best experts on this subject based on the ideXlab platform.
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effect of tangential grooves on piston crown of d i diesel engine with blends of cotton seed oil methyl easter
International Journal of Research, 2012Co-Authors: C V S Reddy, C E Reddy, K H ReddyAbstract:The world’s rapidly dwindling petroleum supplies, their rising cost and the rapid growing of automobile pollutions from fossil petroleum Fuels have led to an intensive search for alternative Fuels to replace diesel Fuel. Direct injection diesel engines are in service for both heavy duty vehicles, light duty vehicles not only in the fields of agriculture and transport sectors, but also stationary engines consume maximum percentage of petroleum based Fuels and have the evident benefit of a higher thermal efficiency than all other engines. However, the direct injection diesel engine emits significant amount of pollutants such as CO, UHC, NOx, smoke etc, which are harmful to the environment. There is a wide variety of alternative Fuels available as renewable Fuels to replace diesel Fuel. Vegetable oils, their properties being close to diesel Fuel, may be a promising alternative for use in diesel engines. The high viscosity and low volatility of these vegetable oils are the major problems for their use in diesel engines. Such problem can be solved by the process of transesterification. In the present work experiments are conducted on D.I. Diesel engine with three different tangential grooved pistons and cotton seed oil methyl esters blended with diesel in various proportions. The effect of three different sizes of tangential grooves on piston crown on the performance and emission characteristics are studied. Brake specific energy consumption decreases and thermal efficiency of engine slightly increases when operating on blended Fuel of 20% Cotton seed oil methyl ester (COME) and 80% diesel (20BD) than that operating on diesel Fuel. From the experimental investigations, it is found that 200 bar is the optimum injection pressure with 20BD blend of COME, which has resulted in better performance and emission characteristics among the biodiesel blends. Based on the results it is concluded that the base line engine with tangential grooved piston configuration(TGP-2) gives maximum performance in all aspects and reduces emissions.
Saccullo Michael - One of the best experts on this subject based on the ideXlab platform.
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Alcohol flexible HD single cylinder diesel engine tests with separate dual high pressure direct Fuel injection
'Elsevier BV', 2021Co-Authors: Saccullo Michael, Nygren Andreas, Benham Timothy, Denbratt IngemarAbstract:Both greenhouse gas (GHG) emissions and local emissions from heavy duty (HD) Diesel engines must be greatly reduced to make transportation sustainable and comply with increasingly stringent emissions regulations. The Fuel flexible engine concept for HD Diesel engines uses a dual Fuel direct injection system in which ignition of the main alcohol Fuel, either methanol or ethanol, is induced by a small Diesel pilot injection delivered via a separate direct injector. The objective of this investigation was to find ways to combine the advantages of conventional Diesel engines with the advantages of low carbon Fuels and to thereby bypass the soot-NOx-trade-off. Experiments were conducted using a modified single-cylinder HD engine and three Fuels (methanol, ethanol, and a reference Diesel Fuel) to determine how the choice of Fuel affected the engine\u27s combustion behaviour, emissions and Fuel efficiency. Injection pressures on the alcohol side were varied up to 1500 bar and the investigation was carried out at low, medium and high speed-load points. The alcohol Fuels significantly outperformed Diesel Fuel under all tested conditions (with and without exhaust gas recirculation (EGR)). Indicated thermal efficiency was increased by up to 3.5%-points and simultaneously soot emissions were lowered by a factor of 40 or more and NOx by 20%. Combustion stability and emissions were in the same range as for Diesel but replacing more than 95 % of the fossil Diesel with an alcohol Fuel
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Alcohol Flexible Dual-Fuel Direct Injection Engine
2020Co-Authors: Saccullo MichaelAbstract:Laws concerning emissions from HD internal combustion engines are becoming increasingly stringent in terms of local emissions and emissions concerning global warming such as lowering tailpipe CO2. New engine technologies are needed to satisfy these new requirements and to reduce fossil Fuel dependency and increase renewable Fuels in the transportation sector. One way to achieve both objectives can be to partially replace fossil Fuels with alternatives that are sustainable with respect to emissions of greenhouse gases and engine out particulates. Also a decrease in NOx can be achieved. Suitable candidates are ethanol or methanol. The thesis presented here summarizes results from publications and additional results presented here with the aim to investigate the possible advantages of combusting low carbon alcohol Fuels in dual-Fuel configuration in a HD Diesel engine - in particular, the potential to greatly reduce particulate emissions and thereby bypass the soot-NOx tradeoff and lowering tailpipe CO2 emissions. It was complimented by additional results presented in the kappa itself.Ethanol sprays were studied in a high pressure/temperature spray chamber at typical engine condition with gas densities of about 27 kg/m^3 at around 550 C and around 60 bar. Spray parameters, such as the liquid cone angle, liquid penetration length and vapor penetration at injection pressures up to 2200 bar, were investigated. The characterization of those sprays was followed by an investigation focusing on the combustion of alcohol Fuels in a single cylinder engine. Methanol, ethanol and E85 were chosen, but because of their poor auto-ignition properties, a pilot Diesel injection was used to initiate the combustion process. One of the alcohol Fuels and Diesel were injected directly but separately, necessitating the use of two separate common rail systems together with a newly designed cylinder head and adapted injection nozzles. The dual Fuel system\u27s combustion properties were compared to those of pure Diesel with the same dual injection strategy. The injection pressure on the alcohol side were varied up to 2000 bar and investigations were carried out at low, medium and high speed-load points, with and without EGR. The investigated low carbon Fuels outperformed Diesel under all tested conditions in terms of thermal efficiency and indicated specific NOx, soot and CO2 emissions. Thermal efficiency was increased by up to 3.5 %-points and simultaneously soot emissions were lowered by a factor of 40 or more and NOx by 20 %. ISCO2 emissions were down by up to 25 %. The Fuel substitution ratio was over 95 % and the combustion stability was not compromised
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Methanol Diesel Dual Fuel Direct Injection in a HD-CI Engine
2018Co-Authors: Saccullo MichaelAbstract:Laws concerning emissions from heavy duty (HD) internal combustion engines are becoming increasingly stringent. New engine technologies are needed to satisfy these new requirements and to reduce fossil Fuel dependency. One way to achieve both objectives can be to partially replace fossil Fuels with alternatives that are sustainable with respect to emissions of greenhouse gases, particulates and nitrogen oxides (NOx). Suitable candidates are ethanol or methanol. The aim of the studies presented here was to investigate the possible advantages of combusting methanol in a heavy duty Diesel engine - in particular, the potential to greatly reduce particulate emissions and thereby bypass the soot-NOx tradeoff. To better understand the Fuel-air mixing process in alcohol Fuel sprays, ethanol sprays were studied in a high pressure/temperature spray chamber with optical access. The experiments were performed at a gas density of 27kg/m3 at 550 C and 60 bar, representing typical operating conditions for a HD engine at low loads. High speed video images of the developing sprays were recorded, enabling measurement of spray parameters such as the liquid cone angle, liquid penetration length and vapor penetration at injection pressures between 500 and 2200 bar. The results obtained provide insight into the Fuel-air mixing process. Having characterized the behavior of alcohol sprays, a second study was conducted to investigate the combustion of alcohol Fuels in a Diesel engine. Because of methanol’s poor auto-ignition properties, a pilot Diesel injection was used to initiate the combustion process. The two Fuels were injected directly but separately, necessitating the use of two separate standard common rail Diesel injection systems together with a newly designed cylinder head and adapted injection nozzles. The studies serve as a proof-of-concept showing that methanol and ethanol can successfully be used in a high pressure Diesel injection system. The dual Fuel system\u27s combustion properties were compared to those of pure Diesel with the same dual injection strategy. Methanol offered comparable combustion efficiencies to conventional Diesel with lower emissions of NOx and significantly lower soot emissions. A design of experiments study was performed to characterize the methanol-diesel system’s behavior in detail at a single speed-load point, and a sweet spot analysis revealed that it may be possible to optimize the tested setup to improve its gross efficiency while maintaining very low soot emissions and low emissions of NOx
Abdul Rahim Ismail - One of the best experts on this subject based on the ideXlab platform.
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Fuel injection pressure effect on performance of direct injection diesel engines based on experiment
American Journal of Applied Sciences, 2008Co-Authors: Rosli Abu Bakar, Abdul Rahim IsmailAbstract:Fuel injection pressures in diesel engine plays an important role for engine performance obtaining treatment of combustion. The present diesel engines such as Fuel direct injection, the pressures can be increased about 100 â 200 Mpa bar in Fuel pump injection system. The experimental investigated effects of Fuel injection pressure on engine performance. Experiments have been performed on a diesel engine with four-cylinder, two-stroke, direct injection. Engine performance values such as indicated pressure, indicated horse power, shaft horse power, brake horse power, break mean effective pressure and Fuel consumption have been investigated both of variation engine speeds - fixed load and fixed engine speed â variation loads by changing the Fuel injection pressure from 180 to 220 bar. According to the results, the best performance of the pressure injection has been obtained at 220 bar, specific Fuel consumption has been obtained at 200 bar for fixed load â variation speeds and at 180 bar for variation loads â fixed speed. The results of the experiment have given as graphics in this paper.
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Fuel injection pressure effect on performance of direct injection diesel engines based on experiment
American Journal of Applied Sciences, 2008Co-Authors: Rosli Abu Aka, Abdul Rahim IsmailAbstract:Fuel injection pressures in diesel engine plays an important role for engine performance obtaining treatment of combustion. The present diesel engines such as Fuel direct injection, the pressures can be increased about 100 â 200 Mpa bar in Fuel pump injection system. The experimental investigated effects of Fuel injection pressure on engine performance. Experiments have been performed on a diesel engine with four-cylinder, two-stroke, direct injection. Engine performance values such as indicated pressure, indicated horse power, shaft horse power, brake horse power, break mean effective pressure and Fuel consumption have been investigated both of variation engine speeds - fixed load and fixed engine speed â variation loads by changing the Fuel injection pressure from 180 to 220 bar. According to the results, the best performance of the pressure injection has been obtained at 220 bar, specific Fuel consumption has been obtained at 200 bar for fixed load â variation speeds and at 180 bar for variation loads â fixed speed. The results of the experiment have given as graphics in this paper.
Vassalos Dracos - One of the best experts on this subject based on the ideXlab platform.
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CFD modelling and numerical investigation of a large marine two-stroke dual Fuel direct injection engine
2021Co-Authors: Yang Renyou, Theotokatos Gerasimos, Vassalos DracosAbstract:This study aims at the development of a CFD modelling approach for the simulation of a large marine two-stroke dual Fuel engine with gaseous Fuel direct injection at high pressure. The developed model employs various sub-models to represent the injection, mixing and combustion processes of the pilot liquid and main gaseous Fuels, which following their customisation are integrated with the ANSYS Fluent software. The shock tube theory and the pseudo-diameter concept are employed to sufficiently represent the gaseous Fuel injection, jet penetration and air entrainment processes. The steady diffusion flamelet model is employed to represent the gaseous Fuel non-premixed combustion process, whereas the pilot Fuel combustion is employed to estimate an ignition kernel. The conserved-equation sources approach is employed appropriately estimating the sources representing the pilot and gaseous Fuels injection and combustion processes. The developed CFD model is first validated based on the previous published results obtained in a rapid compression and expansion machine. Subsequently, the closed cycle of the large marine two-stroke dual Fuel engine is simulated for both the gas and diesel operating modes considering the engine operation at 75% load. The derived in-cylinder pressure variations were validated against respective experimental data, whilst a number of performance and emission parameters for both operating modes are comparatively assessed to delineate the involved phenomena. The derived results demonstrate that the model exhibits adequate accuracy. At the gas mode, the combustion takes place in lower maximum temperature and leaner conditions compared to the diesel mode, resulting in lower NOx emissions. This study contributes to the better understanding of the phenomena and physical processes taking place in large marine two stroke engines with gaseous Fuel direct injection and is expected to benefit the development of future engine designs and the engine settings optimisation targeting to reduce emissions and increase efficiency
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CFD modelling and numerical investigation of a large marine two-stroke dual Fuel direct injection engine
'Informa UK Limited', 2021Co-Authors: Yang Renyou, Theotokatos Gerasimos, Vassalos DracosAbstract:This study aims at developing a CFD model for large marine two-stroke dual Fuel engine with gaseous Fuel direct injection at high pressure. For the gaseous Fuel, the shock tube theory and the pseudo-diameter concept are employed to model the injection, jet penetration and air entrainment processes, whereas its non-premixed combustion is represented by a steady diffusion flamelet model along with a pilot Fuel ignition kernel. Following this model validation, a large marine two-stroke dual Fuel engine closed cycle is simulated for both the gas and diesel modes at 75% load, and the involved phenomena are comparatively assessed. The derived results demonstrate that the gas mode combustion takes place in lower maximum temperature and leaner conditions compared to the diesel mode, resulting in lower NOx emissions. This study is expected to benefit the development of future engine designs and the engine settings optimisation for reducing emissions and increasing efficiency
C V S Reddy - One of the best experts on this subject based on the ideXlab platform.
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effect of tangential grooves on piston crown of d i diesel engine with blends of cotton seed oil methyl easter
International Journal of Research, 2012Co-Authors: C V S Reddy, C E Reddy, K H ReddyAbstract:The world’s rapidly dwindling petroleum supplies, their rising cost and the rapid growing of automobile pollutions from fossil petroleum Fuels have led to an intensive search for alternative Fuels to replace diesel Fuel. Direct injection diesel engines are in service for both heavy duty vehicles, light duty vehicles not only in the fields of agriculture and transport sectors, but also stationary engines consume maximum percentage of petroleum based Fuels and have the evident benefit of a higher thermal efficiency than all other engines. However, the direct injection diesel engine emits significant amount of pollutants such as CO, UHC, NOx, smoke etc, which are harmful to the environment. There is a wide variety of alternative Fuels available as renewable Fuels to replace diesel Fuel. Vegetable oils, their properties being close to diesel Fuel, may be a promising alternative for use in diesel engines. The high viscosity and low volatility of these vegetable oils are the major problems for their use in diesel engines. Such problem can be solved by the process of transesterification. In the present work experiments are conducted on D.I. Diesel engine with three different tangential grooved pistons and cotton seed oil methyl esters blended with diesel in various proportions. The effect of three different sizes of tangential grooves on piston crown on the performance and emission characteristics are studied. Brake specific energy consumption decreases and thermal efficiency of engine slightly increases when operating on blended Fuel of 20% Cotton seed oil methyl ester (COME) and 80% diesel (20BD) than that operating on diesel Fuel. From the experimental investigations, it is found that 200 bar is the optimum injection pressure with 20BD blend of COME, which has resulted in better performance and emission characteristics among the biodiesel blends. Based on the results it is concluded that the base line engine with tangential grooved piston configuration(TGP-2) gives maximum performance in all aspects and reduces emissions.
