A Diagnostic Two-Zone Combustion Model for Spark-Ignition Engines Based on Pressure-Time Data

1988 ◽  
Author(s):  
T. J. AI-Himyary ◽  
G. A. Karim
Keyword(s):  
Spark Ignition ◽  
Combustion Model ◽  
Spark Ignition Engines ◽  
Time Data ◽  
Pressure Time

scholarly journals Modelling combustion in spark ignition engines with special emphasis on near wall flame quenching

2020 ◽  
pp. 146808742097290
Author(s):  
CP Ranasinghe ◽  
W Malalasekera
Keyword(s):  
Combustion Rate ◽  
Fractal Theory ◽  
Pressure Rise ◽  
Spark Ignition ◽  
Spatial Inhomogeneity ◽  
Combustion Model ◽  
Spark Ignition Engines ◽  
Flame Acceleration ◽  
Flame Quenching ◽  
Near Wall

A flame front is quenched when approaching a cold wall due to excessive heat loss. Accurate computation of combustion rate in such situations requires accounting for near wall flame quenching. Combustion models, developed without considering wall effects, cannot be used for wall bounded combustion modelling, as it leads to wall flame acceleration problem. In this work, a new model was developed to estimate the near wall combustion rate, accommodating quenching effects. The developed correlation was then applied to predict the combustion in two spark ignition engines in combination with the famous Bray–Moss–Libby (BML) combustion model. BML model normally fails when applied to wall bounded combustion due to flame wall acceleration. Results show that the proposed quenching correlation has significantly improved the performance of BML model in wall bounded combustion. As a second step, in order to further enhance the performance, the BML model was modified with the use of Kolmogorov–Petrovski–Piskunov analysis and fractal theory. In which, a new dynamic formulation is proposed to evaluate the mean flame wrinkling scale, there by accounting for spatial inhomogeneity of turbulence. Results indicate that the combination of the quenching correlation and the modified BML model has been successful in eliminating wall flame acceleration problem, while accurately predicting in-cylinder pressure rise, mass burn rates and heat release rates.

scholarly journals Numerical Study of Engine Performance and Emissions for Port Injection of Ammonia into a Gasoline\Ethanol Dual-Fuel Spark Ignition Engine

2021 ◽  
Vol 11 (4) ◽  
pp. 1441
Author(s):  
Farhad Salek ◽  
Meisam Babaie ◽  
Amin Shakeri ◽  
Seyed Vahid Hosseini ◽  
Timothy Bodisco ◽  
...  
Keyword(s):  
Numerical Study ◽  
Combustion Process ◽  
Engine Performance ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Combustion Model ◽  
Dual Fuel ◽  
Spark Ignition Engines ◽  
Performance And Emissions ◽  
Hc Emissions

This study aims to investigate the effect of the port injection of ammonia on performance, knock and NOx emission across a range of engine speeds in a gasoline/ethanol dual-fuel engine. An experimentally validated numerical model of a naturally aspirated spark-ignition (SI) engine was developed in AVL BOOST for the purpose of this investigation. The vibe two zone combustion model, which is widely used for the mathematical modeling of spark-ignition engines is employed for the numerical analysis of the combustion process. A significant reduction of ~50% in NOx emissions was observed across the engine speed range. However, the port injection of ammonia imposed some negative impacts on engine equivalent BSFC, CO and HC emissions, increasing these parameters by 3%, 30% and 21%, respectively, at the 10% ammonia injection ratio. Additionally, the minimum octane number of primary fuel required to prevent knock was reduced by up to 3.6% by adding ammonia between 5 and 10%. All in all, the injection of ammonia inside a bio-fueled engine could make it robust and produce less NOx, while having some undesirable effects on BSFC, CO and HC emissions.

scholarly journals Fuel requirements of spark ignition engines

2017 ◽  
Vol 232 (1) ◽  
pp. 22-35 ◽  
Author(s):  
Gautam Kalghatgi ◽  
Richard Stone
Keyword(s):  
Octane Number ◽  
Historical Context ◽  
Hydrocarbon Fuel ◽  
Liquid Hydrocarbon ◽  
Spark Ignition ◽  
Spark Ignition Engines ◽  
Pressure Time ◽  
Octane Rating ◽  
Time Histories ◽  
The Difference

This paper reviews the fundamental requirements of liquid hydrocarbon fuels for spark ignition engines, namely that the fuel should vaporise satisfactorily and burn in a controlled manner. The phenomenon of knock and the development of the octane scale are discussed. The variation in the pressure–time histories for different engines is discussed, together with the reason why this leads to different fuel requirements. The difference in the octane rating tests and the way in which engine downsizing exacerbates these differences in the pressure–time histories are discussed. The applicability of the research octane number and the motor octane number to modern engines is reviewed, together with the phenomena of low-speed pre-ignition and superknock. The effects of the hydrocarbon fuel distillation characteristics on the driveability and the emissions are reviewed and discussed with respect to the historical context and the current legislative requirements. Brief mention is made of other fuel requirements such as the density, the gum content and the aromatic content.

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