Characteristics of HCCI engine operation for additives, EGR, and intake charge temperature while using iso-octane as a fuel
Qian Zuo-Qin, Lü Xing-Cai
School of Energy and Power Engineering, Wuhan University of Technology, Wuhan 430063, China; Institute of Internal Combustion Engine, Shanghai Jiao Tong University, Shanghai 200030, China
Abstract This work investigates the effects of exhaust gas recirculation (EGR) and operation parameters including engine speed, equivalence ratio, coolant-out temperature, and intake charge temperature on the basic characteristics of a single-cylinder homogeneous charge compression ignition (HCCI) engine powered with reformulated iso-octane fuels. The running range of iso-octane HCCI engine can be expanded to lower temperature and more load by adding di-tertiary butyl peroxide (DTBP) in the fuel. The combustion timing advances with the increase of DTBP concentrations, coolant temperature and equivalence ratio. The effects of EGR on the combustion and emissions are remarkable when the EGR rate is higher than 25%, and the combustion phase is sharply postponed and the UHC and CO emissions deteriorate. The intake charge temperature has a moderate effect on combustion and emissions when it is lower than 35 °C; but the combustion timing advances, the combustion duration shortens, and sometimes it leads to knock combustion when the intake charge temperature increases to above 35 °C.
Qian Zuo-Qin, Lü Xing-Cai. Characteristics of HCCI engine operation for additives, EGR, and intake charge temperature while using iso-octane as a fuel. Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 2006, 7(Supplement 2): 252-258.
