核级升降式止回阀通流特性及改进措施仿真研究

Study on the Flow Characteristics and Improvement Measures of Nuclear Lift Check Valves

为解决核级升降式止回阀无法正常开启的问题,通过CFD仿真分析首先研究了不同阀芯开度和上下游压差对升降式止回阀的通流特性的影响。研究发现,流体流量随阀门入口总压和阀芯开度的增大而提高;当阀芯开度为3.0mm与6.0mm时,流体流量相近。当阀芯开度为6.0 mm时,流体对阀芯产生向下的总作用力,说明在实际应用中阀芯难以达到该开度。据此,提出改进策略:针对止回阀前后压差低于特定值时,应适当减轻阀芯质量,其减轻程度需根据实际压差情况确定。

To address the issue of nuclear-grade lift check valves not opening properly,this study first investigates the impact of varying disc openings and upstream-downstream pressure differences on the flow characteristics of lift check valves through CFD simulation analysis.The study finds that the flow increases with both the inlet total pressure and the disc opening;particularly,when the disc opening is at 3.Omm and 6.0mm,the flow shows similar values.Notably,at a disc opening of 6.Omm,the fluid ex-erts a downward total force on the disc,suggesting that it is challenging to achieve this opening in prac-tical applications.Based on these findings,we propose an improvement strategy:the disc weight should be appropriately reduced when the pressure difference before and after the check valve is below a cer-tain value,with the degree of reduction determined according to the actual pressure difference situation.