دانلود مقاله USING A STAND ALONE MODEL TO INVESTIGATE KNOCK CRITERION IN AN SI GAS ENGINE FUELED WITH METHANE
سال انتشار: ۱۳۸۶
محل انتشار: پانزدهمین کنفرانس سالانه مهندسی مکانیک
تعداد صفحات: ۸
omid Jahanian – phD candidate Student K.N.Toosi University of Technology Department of Mechanial Engineering Tehran, Iran
Seyed Ali Jazayeri – Assistant Professor K.N.Toosi University of Technology Department of Mechanial Engineering Tehran, Iran
Reza Ebrahimi – Assistant Professor K.N.Toosi University of Technology Department of Mechanial Engineering Tehran, Iran
Knock limits compression ratio and spark timing in SI engines; that would directly affects the thermal efficiency and output power and may be the cause of mechanical damage in engine.
In this paper, a two zone thermodynamic model is developed using a chemical kinetics mechanism with 20 reactions and 15 chemical species for methane combustion. It is assumed that the flame, with adiabatic temperature is in equilibrium stage. The unburned zone is considered extensively to analyze the conditions that lead to knock. The “Knock Criterion” has been used to forecast the knock intensity. The influence of engine parameters such as spark advance, compression ratio and relative humidity of air intake is studied on knock phenomenon. The experimental engine results from reference works are used to validate the accuracy of our model.