基于CFD方法的低温氦气调节阀工作特性研究  

Study on flowing characteristics of cryogenic helium control valve based on CFD method

作　　者：张彦昭 孙大明[1,2] 丛立 沈惬 Zhang Yanzhao;Sun Daming;Cong Li;Shen Qie(Institute of Refrigeration and Cryogenic,Zhejiang University,Hangzhou 310027,China;Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering,Taiyuan 030001,China;Jiangsu Cryote Cryogenic Technology Co.,Ltd.,Changzhou 213000,China)

机构地区：[1]浙江大学制冷与低温研究所,杭州310027 [2]山西浙大新材料与化工研究院,太原030001 [3]江苏克劳特低温技术有限公司,常州213022

出　　处：《低温工程》2023年第3期10-16,35,共8页Cryogenics

基　　金：浙江省自然科学基金项目(LY21E060008);山西浙大新材料与化工研究院项目(2022SZ-TD015)资助。

摘　　要：根据20 K温区低温氦气调节阀的运行工况,基于CFD方法对一台DN25低温氦气调节阀内的速度、压力、温度等流动参数进行了仿真研究。得到不同开度和压差下,流线和漩涡的分布情况,确定阀内物理参数大梯度变化位置及规律。针对阀芯与阀座的微小缝隙,研究了氦气从亚音速到超音速变化中压力、速度、马赫数和温度变化特性。计算结果显示,氦气在压力比为0.495时达到临界状态,与基于理想气体节流膨胀理论计算的临界压力比仅相差4.2%。研究结果揭示了调节阀内低温流体性质变化和流动规律,为预测阀门阻塞流发生条件提供了依据。Numerical simulation techniques were used to simulate flow parameters(velocity,pressure,temperature)in the valve under operating conditions in the 20 K temperature region.The flow line and vortex distribution were obtained for different openings and differential pressures,and laws of large gradient changes of physical parameters in the valve were determined.The pressure,velocity,Mach number,and temperature variation characteristics in the transition from subsonic to supersonic speed for the tiny gap between the spool and the valve seat were also studied.The results show that the helium gas reaches a critical state at a pressure ratio of 0.495,which is only 4.2%different from the critical pressure ratio calculated based on the ideal gas throttling expansion theory.This research provides a reference for understanding the change of the nature and flow pattern of the cryogenic fluid in the regulating valve and predicting the conditions of chocked flow occurrence.

关 键 词：低温调节阀 节流膨胀 阻塞流 数值模拟 

分 类 号：TH134[机械工程—机械制造及自动化] TB663[一般工业技术—制冷工程]