Effects of intake temperature on performance and operation range of an HCCI engine fueled with n-butanol

Abstract

To investigate the effects of intake temperature on the performance and operation range of HCCI engine fueled with n-butanol, the 2 nd cylinder of a water-cooled, naturally aspirated diesel engine with 2-cylinder was modified to operate on HCCI combustion mode. The indicated mean effective pressure (IMEP), indicated thermal efficiency () and operation range were compared and analyzed under the conditions with different intake temperature at engine speed of 1000r/min. The experimental results show that the IMEP and ITE are maximized at 140℃ and reduced with the increase or reduction in intake temperature at lower excess air ratio (λ). However, at higher λ, the IMEP and ITE are increases as the intake temperature rises. The operation range of the HCCI engine is obviously expanded when the intake temperature varies from 110℃ to 140℃ while is almost constant after the intake temperature is over 140℃. All of the results indicated that a lean mixture accomplish with a reasonable higher intake temperature may improve the combustion of HCCI engines.