Showing papers on "Spark-ignition engine published in 2012"
TL;DR: In this article, an experimental study was conducted in a port fuel-injection, spark-ignition engine fuelled with blends of gasoline and n-butanol at different spark timings and EGR rates.
310 citations
TL;DR: In this paper, an ANN model based on standard back propagation algorithm was developed to predict the brake specific fuel consumption, effective power and average effective pressure and exhaust gas temperature of the methanol engine.
156 citations
TL;DR: In this paper, a comparison between experiments and Large-Eddy Simulation (LES) of a spark ignition engine on two operating points: a stable one characterized by low cycle-to-cycle variations (CCV) and an unstable one with high CCV is presented.
143 citations
TL;DR: In this paper, a single cylinder diesel engine was modified to operate as a biogas operated spark ignition engine and the performance, emission and combustion characteristics with different compression ratios are compared.
140 citations
TL;DR: In this article, the effect of adding small amounts of hydrogen to gasoline-air mixtures on the performance and exhaust emission characteristics of a spark ignition engine was investigated, including thermal efficiency, specific fuel consumption, cyclic variations of the IMEP, and emissions of CO, NO and unburned hydrocarbons.
119 citations
TL;DR: In this paper, an improved ammonia combustion mechanism was validated for the flame structure prediction of ammonia, hydrogen, oxygen, argon flames investigated at several low pressures and for various conditions of equivalence ratio and of initial hydrogen content.
117 citations
TL;DR: The use of hydrogen derived methanol in spark-ignition engines forms a promising approach to decarbonizing transport and securing domestic energy supply as discussed by the authors, however, there is a clear distinction between engines specifically designed for hydrogen or methanoline operation and flex-fuel engines, which should also run on gasoline.
93 citations
TL;DR: In this article, a method that dynamically calculates the knock threshold necessary to determine the knock event is proposed to resolve cycle by cycle the knock intensity related to an individual engine cycle without setting a predetermined threshold.
92 citations
TL;DR: In this paper, the results of the tests carried out in a naturally aspirated vehicle spark ignition engine fueled with different hydrogen and methane blends were presented, showing that the best balance between thermal efficiency and pollutant emissions was observed with the 30% hydrogen and 70% methane fuel blend.
76 citations
TL;DR: In this paper, a new synthesis method is presented to control air-fuel ratio (AFR) in spark ignition engines to maximize the fuel economy while minimizing exhaust emissions, where the time-varying delay in the control loop is first approximated by Pade approximation to render the system dynamics into non-minimum phase characteristics with time varying parameters.
64 citations
TL;DR: In this paper, high-speed imaging results of spray impingement onto the liner of a direct-injection spark-ignition engine, as well as crank-angle resolved wall heat flux measurements at the observed locations of fuel impingements were analyzed to extract mean and standard deviation statistics of spray images and heat flux signals.
TL;DR: In this article, the effect of compressed natural gas (CNG) and 18% hydrogen blended compressed Natural Gas (HCNG) on a retrofitted gasoline genset engine's performance, emissions, deposits and lubricants under long duration testing was investigated.
TL;DR: In this paper, the effects of neat bioethanol combustion on the performance and emission reduction characteristics of a spark ignition (SI) engine at various air temperature conditions were investigated, and the results were compared to those for conventional gasoline fuel.
TL;DR: In this article, the performance and indicated efficiency of the engine, the combustion processes, and the emissions of nitrogen oxides were investigated in a hydrogen-fueled, spark-ignition engine.
TL;DR: In this article, the combustion characteristics of a naturally aspirated spark ignition engine, intended for installation in vehicles, fueled with different hydrogen and methane blends, were analyzed in a wide range of speeds at equivalence ratios of 1, 0.8 and 0.7 and at full load.
TL;DR: In this article, a mathematical model which was developed to predict steady state performance of a biomass downdraft gasifier/spark ignition engine power system is described, which can be used for more accurate adjustment of design parameters of the gasifier and the engine in order to provide the higher overall efficiency of the system.
TL;DR: In this article, an optical study of combustion in a spark-ignition research engine running with direct injection and port injection of hydrogen is presented, and the results of the experiments are analyzed with respect to laminar and turbulent burning velocities.
TL;DR: In this article, the authors provided an overview of the quantitative levels of exergy destruction during the combustion process as function of engine operating and design parameters, and for eight fuels including isooctane (base), methane, propane, hexane, methanol, ethanol, hydrogen and carbon monoxide.
Abstract: SUMMARY
The second law of thermodynamics provides different perspectives compared with the first law, and provides the property exergy. Exergy is a measure of the work potential of energy from a given thermodynamic state. Unlike energy, exergy may be destroyed, and for reciprocating engines, the major source of this destruction is during the combustion process. This paper provides an overview of the quantitative levels of exergy destruction during the combustion process as function of engine operating and design parameters, and for eight fuels. The results of this study are based on a spark-ignition, automotive engine. The amount of exergy destroyed during the combustion process has been determined as functions of speed, load, equivalence ratio, start of combustion, combustion duration, combustion rate parameters, exhaust gas recirculation (EGR), inlet oxygen concentration, and compression ratio. In addition, design parameters that were examined included expansion ratio and the use of turbocharging. The fuels examined included isooctane (base), methane, propane, hexane, methanol, ethanol, hydrogen and carbon monoxide. For the part load base case (1400 rpm and a bmep of 325 kPa) using isooctane, the destruction of exergy was 20.8% of the fuel exergy. For many of the engine operating and design parameter changes, this destruction was relatively constant (between about 20 and 23%). The parameters that resulted in the greatest change of the exergy destruction were (1) equivalence ratio, (2) EGR, and (3) inlet oxygen concentration.
For the base case conditions, the exergy destruction during the combustion process was different for the different fuels. The lowest destruction (8.1%) was for carbon monoxide and the highest destruction (20.8%) was for isooctane. The differences between the various fuels appear to relate to the complexity of the fuel molecule and the presence (or absence) of an oxygen atom. Copyright © 2011 John Wiley & Sons, Ltd.
TL;DR: In this article, the potential of exhaust gas recycle in a downsized, turbocharged spark-ignition engine has been extensively analyzed, at different speed and load, and the most severe conditions for knock onset have been investigated.
TL;DR: In this article, the performance and emissions of a gasoline engine using different research octane number (RON) gasolines (91, 93, 95 97, and 98 RON) at varying spark timing (ST) has been presented.
TL;DR: In this article, a steady-state thermal analysis was performed to evaluate the temperature gradients in the standard and two different partially stabilized ceramic coated pistons by using Abaqus© finite element (FE) software.
TL;DR: In this article, the performance and emission characteristics of an 11 L spark ignition engine using natural gas-hydrogen blends with various CO 2 contents were examined, and an optimization strategy for controlling the excess air ratio and the spark advance timing was assessed.
TL;DR: In this paper, the effects of exhaust gas recirculation on the behavior of a spark ignition engine fueled by hydrogen-blended low-calorific biogas were investigated, and its performance and emission characteristics were compared with those of the lean burn engine investigated in previous work.
TL;DR: In this paper, a single-stage pressure reducer was selected as an LPG evaporator, to take advantage of an additional pre-heating of the liquid LPG that allows higher power output than a two-stage device of the same size.
TL;DR: In this article, an experimental study on the performance and exhaust emissions of a commercial hydrogen fueled spark ignition engine (HFSIE) was performed at partially and full wide open throttle (50% and 100% WOT) positions.
TL;DR: In this paper, the performance of several reaction mechanisms for the oxidation kinetics of ethanol-air mixtures is compared, and the best performing mechanisms are used to calculate the laminar burning velocity and flame thickness of these mixtures in a wide range of temperatures, pressures and compositions.
01 Jan 2012
TL;DR: The Ultraboost project aims to develop a highly pressure-charged, downsized, spark ignition engine that is capable of a 35% reduction in tailpipe CO 2 emissions over a naturally aspirated 5.0 L V8 while still maintaining performance, emissions and transient response.
Abstract: The Ultraboost project outlined in this paper seeks to develop a highly pressure-charged, downsized, spark ignition engine that is capable of a 35% reduction in tailpipe CO 2 emissions over a naturally aspirated 5.0 L V8 while still maintaining performance, emissions and transient response. This project is especially ambitious since, in order to achieve this level of fuel economy improvement, a 60% reduction in engine displacement is targeted with a BMEP of greater than 30 bar. What is more, achieving these targets in a gasoline engine with stoichiometric fuelling requires careful design and component selection in order to address the many challenges surrounding gasoline combustion under such high boost pressures. This paper describes a critical examination of the competing requirements of a heavily downsized, gasoline engine with a specific focus on the role of the boosting system in delivering these requirements. From this analysis, the optimal base boosting system configuration is investigated. In addition, a number of boosting technologies, ranging from the novel to the more traditional, are discussed in view of their ability to fulfil a role on the Ultraboost engine. A set of assessment criteria is presented in order to facilitate the selection process. Finally, a 1-D GT-Power model of the Ultraboost engine equipped with the different boosting systems was used to generate an informed rating of all boosting options and permit a reliable comparison with respect to the targets of the project.
TL;DR: In this paper, the performance and emission characteristics of a conventional twin-cylinder, four stroke, spark-ignited (SI) engine that is running with methane-hydrogen blends have been investigated experimentally.
Journal Article•
TL;DR: In this article, an experimental and theoretical investigation of the influence of the compression ratio on the brake power, brake thermal efficiency, brake mean effective pressure and specific fuel consumption of the Ricardo variable compression ratio spark ignition engine was conducted.
Abstract: The need to improve the performance characteristics of the gasoline engine has necessitated the present research. Increasing the compression ratio below detonating values to improve on the performance is an option. The compression ratio is a factor that influences the performance characteristics of internal combustion engines. This work is an experimental and theoretical investigation of the influence of the compression ratio on the brake power, brake thermal efficiency, brake mean effective pressure and specific fuel consumption of the Ricardo variable compression ratio spark ignition engine. Compression ratios of 5, 6, 7, 8 and 9, and engine speeds of 1100 to 1600 rpm, in increments of 100 rpm, were utilised. The results show that as the compression ratio increases, the actual fuel consumption decreases averagely by 7.75%, brake thermal efficiency improves by 8.49 % and brake power also improves by 1.34%. The maximum compression ratio corresponding to maximum brake power, brake thermal efficiency, brake mean effective pressure and lowest specific fuel consumption is 9.The theoretical values were compared with experimental values. The grand averages of the percentage errors between the theoretical and experimental values for all the parameters were evaluated. The small values of the percentage errors between the theoretical and experimental values show that there is agreement between the theoretical and experimental performance characteristics of the engine.