Study On Grid And State Equation In Diesel Engine Working Process Simulation

Grid has been a bottleneck for simulations of internal combustion engine. Taking KIVA former program as a grid generation tool, respectively from two different arrange of valves, some methods to improve the grid that connected between combustion chamber and cylinder are proposed on the base of analyzing and absorbing the KIVA program. Based on the improved methods, the grid of diesel engine has been made and used in the simulation.Diesel always worked in the supercritical environment. This condition did not meet ideal gas state equation. If the ideal gas state equation has still been used in combustion mechanism, the results may be unreliable. However, with KIVA for representative, the reason why so many calculations used ideal gas state equation is saving time and efficiency. With the development of science and technology, computer software and hardware have greatly progress. It is the time to make use of the real gas state equation in the simulation. It is of great importance to study the real gas state equation for the combustion mechanism.In this article, taking KIVA program for platform, a diesel engine is chosen as the research object. Based on the cubic state equation and the ideal gas state equation, the diesel engine operating process simulation is carried out, and this paper focuses on fuel evaporation process. The calculation results based on different state equations are given for comparison. The results show:because of the different fuel evaporation process and the specific heat value, the temperature, the pressure and the kindling point have significant difference.