| Summary: | 碩士 === 國立成功大學 === 系統及船舶機電工程學系碩博士班 === 94 === The homogeneous charge compression ignition (HCCI) engine can enhance the thermal efficiency of DI engine and reduce the formulation of pollutant. Because the homogeneous charge compression ignition needs to adopt the formation of homogeneous mixture gas in the intake process, it is very important to analyzing the combustion performance of a homogeneous charge compression ignition engine with different intake premixed gas and its contents.
This article is aimed at the KUBOTA RK-125 which is a single cylinder direct injection diesel engine, and carries out the numerical simulation. KIVA3V-RELEASE2 is used as the subject of the program, according to modifying the different intake gas contents in program adopting different proportion of the gasoline, ethanol and methanol under different engine speeds. Also the intake port and in-cylinder distribution of equivalence ratio, heatrelease rate of engine, flow and temperature field are investigated for different intake premixed gas and its contents, and the results between the simulation and the experiment will be compared .
The research has already entered the gasoline, ethanol and methanol successfully in the intake process, and succeed in initialing the chemical reaction mechanism of KIVA3V-RELEASE2 using the RNG model of turbulence mixing combustion. The simulation result show that following proportion being the higher, heat of vaporization supreme methanol occur burn in lower temperature and its pressure peak value will rise because of increasing in-cylinder absorption of heat . The simulation combustion process in this research are expected to be a reference value when the close cycle diesel engine system installs with HCCI engine in the future.
|
|---|
