Advanced idea on Fuel Droplet Breakup Model for Diesel Combustion Calculation

抄録

Our diesel combustion calculation code using chemical calculation with a reduced elementary reaction model has enough accuracy for the practical use on engine developments. To aim for more calculation accuracy, a new idea was adopted to the fuel droplet breakup model. This idea is to apply a variable model constant to the breakup model. The model constant is varied according to the needle valve lifting of the injector. It works that the breakup right after the injection start is promoted by the variable model constant. And the heat release ratio estimation is remarkably improved. Some calculation results are shown in this paper, and the validity of the idea is discussed here showing some calculation results from an unstable in-injector flow and observations of spray characteristics with an experimental enlarged injector apparatus. In addition, an originally developed injector model is explained.