Open AccessEffect of specific heat ratio on heat release analysis in a spark ignition engine
Author(s) -
Rahim Ebrahimi
Publication year - 2011
Publication title -
scientia iranica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.299
H-Index - 51
eISSN - 2345-3605
pISSN - 1026-3098
DOI - 10.1016/j.scient.2011.11.002
Subject(s) - combustion , compression ratio , spark ignition engine , equivalence ratio , thermodynamics , heat capacity ratio , spark (programming language) , mean effective pressure , ignition system , materials science , gasoline , heat capacity rate , mechanics , chemistry , heat transfer , physics , computer science , organic chemistry , programming language , combustor , heat spreader
The specific heat ratio used in heat release calculations plays a crucial role in the determination of combustion parameters. In this study, the effects of assumed specific heat ratio on the heat release analysis of engine pressure data are studied in a spark ignition engine, using natural gas and gasoline fuels. The experiments were carried out with the spark timing adjusted to the maximum brake torque timing, at an equivalence ratio of ϕ=1 and a speed engine of N=3300rpm. The combustion parameters are obtained from the heat release rate, which obtained from the first law of thermodynamics during a cycle. The results show that the combustion parameters have high sensitivity to the variation and first derivative of the specific heat ratio. The results also show that the influence of the first derivative of the specific heat ratio on the combustion parameters for natural gas operation is higher than that for gasoline operation. Moreover, the first derivative of the specific heat ratio for determination of combustion parameters should not be ignored