Assessing the factors affcting si engine cycle-tocycle variatios at idle

摘要

The extent of the cycle-to-cycle variations of charge composition and their contributions to th variaitons in Gross Indicated Mean Effective Pressrue (GIMEP) in a spa4rk ignition (SI) engine at idle are assessed.The methjodology is to use a set of charge perturbation experiments to determine the sensitivity of the engine output parameters to the charge compostion variaitos.Then therouhg this sensitivity matrix,the observed engine outpout variatios at idle are invested to obtain the charge variations.