过热水喷流发动机喷管中的流动数值模拟与基本特性分析

文章基于蒸发冷凝模型建立了闪蒸相变模型,对过热水喷流发动机喷管中的两相流动过程进行了数值模拟,发现高温高压流体在流动的过程中伴随着相变和膨胀的发生,两相流体在喷管收缩段、喉部和扩张段中流动特性各不相同,与实验数据进行对比验证了模型的准确性。研究了喷管形状对流动基本特性的影响,发现扩张比和扩张角对两相流在喷管中的相变和膨胀过程影响不同。该文所做研究对揭示两相流闪蒸相变机理、寻求各参数之间的匹配关系有着重要意义,可以为设计过热水喷流发动机提供理论基础。

Numerical simulation and analysis of the basic characteristics of the flow in the nozzle of a hot water jet engine

A flash evaporation model is established based on the evaporation-condensation model. The pro-cess of two phase flow in the nozzle of a hot water jet engine is simulated. It is found that the fluid at a high temperature and pressure flows through the nozzle with the process of phase change and expansion. The flow characteristics of the fluid in the nozzle contracted section, throat and expanded section are different. The accuracy of the model is verified by comparing with the experimental data. The effect of nozzle shapes on the flow characteristics is studied. It is found that the effects of the expansion ratio and expansion angle on the process of the phase change and expansion of the two phase flow are different. This paper helps to re-veal the mechanism of the flash evaporation and the matching relationship between each parameter. It can afford a theoretical basis to design a hot water jet engine.