A Numerical Simulation Study Of Diesel Engine In-cylinder Flow And Combustion Using KIVA-3V

The decrease of the energy and the pollution of the environment have been the two serious problems in the world. It has become a highlight to researching the operation process especially combustion process for IC-engine. The method of numerical simulation can effectively forecast the complete performance of IC-engines and partly replace some engine experiment, and carry on various parameter researches in different operational modes without the time and space limit, guide the designs of engines with the new combustion system, optimize the performance of original engines. It can also forecast the power and exhaust emissions of the engine fired with various fuels. Therefore the method of numerical simulation has very powerful vitality and many advantages.KIVA-3V, a multidimensional simulation program developed by U.S. Los Alamos National Laboratory, is introduced in this thesis. By means of digestion, debug and absorption, the micro-computerization of the codes is successfully conducted and the necessary output code is added. With the softwares of Fieldview and Tecplot, the calculated results are visualized to draw animating contour plots and average performance charts.Based on KIVA-3V, the operation process in cylinder of a type 1105 diesel engine modified to a DI engine is simulated, the detail information of the flow field in cylinder and average performance graphic charts are obtained and compared with the experimental data. This paper also discusses the affection of the air motion and combustion process on the different geometric parameters, the loads, the swirl ratios and the injection times.A new offering, liquid DME (dimethyl ether), has expanded the fuel library of KIVA-3V. The thermal properties such as the latent heat value, the surface tension, etc. of DME are written to the KIVA codes. By comparing the results of the numerical simulation of DME and diesel fuel, it can be obtained the conclusions that DME is a kind of green alternative fuel and DME engine has lower emissions and more smooth work.