诱导轮液氧空化流动特性数值仿真  

Numerical simulation on LOX cavitating flow characteristics of inducer

作　　者：项乐 李春乐[1] 许开富[1] 张凯 XIANG Le;LI Chunle;XU Kaifu;ZHANG Kai(Xi'an Aerospace Propulsion Institute,Xi'an 710100,China)

机构地区：[1]西安航天动力研究所,陕西西安710100

出　　处：《火箭推进》2024年第3期11-18,共8页Journal of Rocket Propulsion

基　　金：国家重大基础研究项目(613321)。

摘　　要：诱导轮是决定涡轮泵抗空化能力的关键部件,为了揭示诱导轮内部液氧空化流动特性,建立了基于能量方程源项修正的低温空化数值计算方法,同时耦合了液氧物性随温度变化关系,利用经典低温空化和诱导轮空化试验数据进行了充分验证,对某三叶片诱导轮内部液氧空化流动进行了仿真分析。结果表明:低温介质空化过程中与周围液体存在剧烈的能量交换,但只有一部分空化溃灭释放的热量被传递至周围流场,通过调节能量方程源项中空化溃灭释热比例可使空化区尾部温度场预测精度提升0.5%。对比等温计算,考虑热效应后,液氧空化区范围和内部汽相体积分数大幅减小,对流道的阻塞程度降低,有效延缓了诱导轮扬程断裂。对3种温度下液氧空化流动进行仿真研究,发现液氧温度越高,空化范围越小,同时空化区温降越大,诱导轮空化性能改善也越显著。Inducer is key component which determinates the anti-cavitation ability of a turbopump.In order to clarify the LOX cavitation flow characteristic inside the inducer,a novel numerical simulation for cryogenic cavitation method has been built based on the correction of energy equation source term,and the relationship between physical properties and temperature variation is coupled.The numerical method has been verified by the classical cryogenic cavitation and the inducer cavitation experimental data.Then,a simulation analysis of cavitation flow inside a three-bladed inducer are conducted,and it is found that:there is strong energy exchange between cavities and the surrounding liquid during the cryogenic cavitation,but only part of the heat released by the cavitation collapse can be transferred to the surrounding liquid.By adjusting the heat release ratio of heat by cavitation collapse in the source term of energy equation,the prediction precision of temperature field near the cavity rear can be improved by 0.5%.Compared with isothermal calculation results,the LOX cavitation area and vapor volume fraction decrease remarkably when the thermal effect is considered,thus the blocking effect to the blade channels decreases either,and the inducer head breakdown is delayed effectively.The simulation study of the LOX cavitation flow at different temperature shows that the higher the liquid oxygen temperature,the smaller the cavitation range,and the larger the temperature drop in the cavitation region,the more significant the improvement of cavitation performance for the induced wheel.

关 键 词：诱导轮 液氧空化 数值仿真 空化模型 热效应 

分 类 号：TV131.32[水利工程—水力学及河流动力学] V431[航空宇航科学与技术—航空宇航推进理论与工程]