RESEARCH OF RESIDUAL LIFETIME OF DIESEL ENGINES FUEL INJECTION EQUIPMENT BY MEANS OF FUEL INJECTION MATHEMATIC SIMULATION

Abstract

On the basis of the engineering practices of the last 3-4 decades, it is known, tested and proven that, while mathematical models provide reliable descriptions of processes, cycles or physical phenomena, in theoretical research the theory of small deviations is comprehensively preferable to any experiment on regulating characteristics. Considering the fact that all parameters and characteristics are sometimes interconnected by nonlinear dependences, it is impossible to distinguish the influence of a specific parameter on the sought-for value, and can be even hazardous if the determinant argument or its derivative has extreme values. The role of mathematic simulation to determine the residual lifetime of the fuel injection equipment of diesel engines was established. It was also noted that for a reliable description of the processes going on in the fuel injection equipment it is advisable to use the method of small deviations. The mathematical model is based on the known physical laws that describe the interdependence of the two groups of parameters: engine variables and performance parameters - both within the groups and between them. The transition of classical differential equations describing the processes of fuel supply and injection taking into account fuel leaks in precision pairs to the equations with small deviations of parameters is shown. An analysis of correlations between the parameters of injection, fuel supply and fuel leakage was carried out and the most influential parameters were found. The influence coefficients are found and correlations between the influence coefficients and the corresponding parameters are constructed. We used the correlations found to describe the influence of the technical condition of precision pairs on the engine performance indicators. The correlations between the change in injection patterns and small deviations of the parameters describing technical condition of precision pairs are also established.