针阀头部结构对喷油嘴内部流动影响计算分析

Simulation Analysis on Flow Characteristics in Nozzle Effected by Needle's Head Structure

针阀头部结构影响喷油嘴内部流动特性,而且强烈地影响喷雾特性和混合气的形成及燃烧过程。本文以某SAC喷油嘴为研究对象,使用CFD计算的方法详细地研究了喷油嘴针阀头部结构对喷油嘴内部流动特性的影响规律。计算结果表明:针阀头部结构对发动机标定工况时喷油嘴内部流动特性影响较小,但对怠速工况时影响相对较大。针阀头部密封面直径和密封角对喷油嘴内部流动特性影响相对较大。

Spray properties and mixture formation strongly affected by injector structure. In this paper, a SAC nozzle is used as the research object, and the influence of needle valve head structure on flow characteristics inside the nozzle is studied in detail using the CFD method. The calculation results show that the influence of needle valve head structure to internal flow characteristics in the nozzle is smaller in the rated power condition of engine and there is the relatively large impact in the idle state of the engine. The seal surface diameter and seal angle in the head of needle valve have a relatively large impact on the internal flow characteristics of nozzle.