柴油机高压共轨轨腔的三维数值模拟计算分析

高压共轨是控制柴油机排放的一项新技术，国内还处于发展阶段，因此具有研究的实际意义。通过建立高压轨腔的三维不可压流体力学模型和流体力学边界条件，利用SIMPLE计算方法，并引入SST k-ω湍流模型，模拟计算三种不同截面轨腔的压力场和速度场，分析壁面夹角与轨腔内流场的关系。结果表明：在横截面面积相同的情况下，出口中心线与轨腔壁面的夹角小于90°且大于80°的轨腔改善了轨腔内的流场特性分布。CFD数值模拟的研究方法能缩短研发周期并且便于改变模型参数。是研究高压共轨的有效方法。

Numerical Simulation and Analysis of the 3D Flow in Cavity of High Pressure Common Rail of Diesel

High Pressure Common Rail is a new technology for controlling diesel engine emission and still is in development stage in China, so it has the practical significance of studying. This paper establishes the three-dimensional incompressible fluid mechanics model and fluid dynamics boundary conditions in the high pressure rail cavity. This paper uses SIMPLE calculation method, and introduces the SST k-ω turbulence model to simulate the cross-section of three different rail cavity pressure and velocity fields. The results show that the cavity of which the angle between the export centre line and rail cavity wall is less than 90° and more than 80° can improve distribution of the flow, when the cross-sectional area of the same circumstances. CFD numerical simulation methods can not only shorten the development period and can be easy to change model parameters, but is also the effective way to research High Pressure Common Rail.