Predictive analysis method and system for engine performance and control program for use in the same

Abstract

In a computer system for analyzing the flow of an intake/exhaust gas of, for example, a four-cycle multi-cylinder engine through application of CFD, the dimension of a space where the flow of the intake/exhaust gas is analyzed can be selected with respect to each of four processes, that is, intake, compression, expansion and exhaust processes, of each cylinder (in selecting step S), and a physical model for simulating the flow of the intake/exhaust gas from a part of an intake system to a part of an exhaust system of the engine in the dimension selected with respect to each of the four processes is set (in model setting steps S, S, Sand S). The flow of the intake/exhaust gas is subjected to a CFD operation using the physical model, and chemical reactions caused in combustion is simulated (in operating steps S, Sand S), so as to output an output about engine performance on the basis of the results of these simulation operations. Thus, while keeping sufficiently high accuracy in the analysis, time required for the CFD operation can be reduced as much as possible, resulting in improving the utility as a design/development tool.