Pressure Control Design of High-Pressure Fuel Pipe

Abstract

In order to ensure the normal operation of the engine, the stability of the fuel supply system must be ensured. The fuel supply system needs to obtain fuel from the outside, and then pressurized into the high-pressure oil pipe, and then input into the engine cylinder. Therefore, the fuel parameters in the components of the fuel supply system affect each other. In this paper, a mathematical model is established to describe the relationship between the fuel parameters of each part of the fuel supply system, and then the stability of the fuel supply system can be controlled by controlling some parameters under given conditions. We intercept a very short time, analyze the mutual transfer of fuel in the fuel supply system through the micro element method, and establish the differential equations. Because some differential equations are more complex, it is difficult to find the formula solution, so we discretize the differential equations and get a group of recurrence relations. After calculating the initial state and related parameters, the fuel pressure parameters and fuel density parameters of each part of the fuel supply system at each time can be obtained recursively. Because the pressure and density of the fuel can express each other, we focus on the density parameter of the fuel, and do the conversion when the pressure is needed. On the basis of this group of recursive relations, we established an optimization model of fuel pressure control in high-pressure oil pipe: Taking the fuel supply time of one-way valve as decision variables, minimizing the difference between fuel pressure and standard value at each time as optimization objective, taking the practical significance of each physical quantity as constraint condition, and gave a discrete algorithm.