柴油机燃油喷射系统的数值模拟及计算结果分析

建立了柴油机燃油喷射系统数学模型，包括喷油泵端、喷油器端和高压油管三个子模型，在计算中对燃油压缩性系数的计算公式作了适当的修正；在分析高压油管内部流动特征的基础上，建立了流动的控制方程，并推导了变密度情况下的特征线计算公式；同时认为高压油管内压力波传播速度非定常，较为详细地考虑和分析了各影响因素及其简化方法，并着重对计算结果进行了深入的分析，为进一步精确地描述燃油喷射系统工作机理提供了依据。

A SIMULATION OF FUEL INJECTION SYSTEM FOR DIESEL ENGINE AND ANALYSES OF ITS COMPUTATION RESULTS

In this paper,Aset of mathematic model for Diesel fuel injection system was developed,inchding suh-model of injector,sub-model of fuek injection pump,and sub-model of highpressure fuel pipe. Appropriate correction was made on the formula of the fuel compress-ibility in this calculation,On the base of analyzing the flow characteristic in high pressure fu-el pipe,control equations of the flow were set up and from it we get the calculation formulaof the characteristic line under the condition of varied density, The sonic velocity in highpressure fuel pipe is considered to be non-steady. We also carefully think of and analyzemany influential factors and its simplified methods. The calculation results were analyzed indetails,which supplies the basis for accurately describing the working mechanism of fuel in-jection system.