Combustion in a spark-ignition engine

This paper describes a simple analysis for the prediction of pressure withi n a spark ignition engine. This is done by modelling the combustion process using the Wieb function approach, which is an exponential function in the form y = 1 - e(-axm), to calculate the rate of fuel burned. By careful sele ction of a and m, any spark ignition engine with any combustion chamber sha pe and any specified dimensions can be assessed by this model. The validity of the model has been tested by comparing the model results with those obt ained from running the engine under the same operating conditions. The resu lts obtained from the theoretical model when compared with those from the e xperimental ones show a good agreement. Also, the effects of the many opera ting conditions, such as compression ratio, engine speed, and spark timing have been studied. (C) 2000 Elsevier Science Ltd. All rights reserved.