柴油机涡流室结构参数对涡流室内空气流动特性影响的研究──第Ⅰ部分：涡流室形状的影响

Effects of Swirl Chamber Structural Parameters on Air Motion in the Swirl Chamber of Diesel Engines(Part I Effects of Swirl Chamber Geometry)

本文建立了一个用于计算涡流室内各向异性湍流的ｋ－ε湍流模型，结合双色氩离子激光多普勒测速仪的测量结果，利用经过改进的Ｋｉｖａ－Ⅱ程序计算了吊钟型、ＣｏｍｅｔＶ型及球型等３种典型柴油机涡流室内的空气流动特性，并与部分实验结果进行了比较。研究结果揭示了各涡流室内的空气流动特性，并阐明了涡流室形状的影响规律。

This paper presents a flow model which is composed of an anisotropic k-εturbulence model and a set of governing equations for the transport of mass,momentum and energy.The Kiva-Ⅱcode has been updated by introducing this flow model and widening its applicable scope to swirl chamber diesel engine.By using the experimental data of two-color laser Doppler velocimetry as the boundary conditions,the updated Kiva-Ⅱ code is used to numerically clarify the flow characteristics in the three typical kinds of swirl chamber geometries,that is,the bell type,the Comet V type and the ball type swirl chamber,some numerical results are compared with the LDV measurement.The results obtained clearly show the processes such as the swirl formation and development, the changes of swirl characteristics and swirl number,the changes of turbulent quantity distribution and the gas temperature distribution.The effects of swirl chamber geometry on flow characteristics are then derived.