基于FLUENT的球型止回阀流场CFD模拟分析

为了研究球型止回阀内部流场流动状态和水力特性,以及阀门自行关闭所产生的水击现象,采用计算流体力学方法,建立止回阀内部流场计算模型和球体运动数学模型,并应用动网格技术求解止回阀关闭过程中阀体内速度场、压力场分布,以及球体表面静压曲线变化。模拟计算得出:止回阀内球体表面存在负压区域,造成汽蚀现象;阀体壁面附近存在漩涡流,这将加强壳体震动,削弱其工作效率。为消除止回阀内负压区域和漩涡流等不稳定流态,对其入口部件进行结构改进,减少扰流作用,模拟结果表明:球体表面负压区域减小,汽蚀现象改善,阀体中漩涡流消失,止回阀工况较改进前稳定。

CFD simulation analysis of the ball type check valve flow field based on FLUENT

In order to study the ball type check valve interior flow field flow and hydraulic characteristics, as well as the water hammer phenomenon caused by valve self-closing, using computational fluid dynamics method to establish check valve interior flow field calculation model and sphere motion mathematical model, and use dynamic mesh technique to study the velocity field distribution, the pressure field distribution and the variation of spheroid surface static pressure in the process of valve closing. The simulation results show that there is a negative pressure area on the surface of the ball in the check valve, which causes the cavitation phenomenon. There is a vortex flow near the valve body, which will strengthen the vibration of the shell and weaken the work efficiency. To eliminate the areas of negative pressure and unsteady flow state of vortex in the check valve, the structure of the inlet part is improved to reduce the turbulence effect. Simulation results show that the negative pressure area of the sphere surface is reduced and the cavitation is improved, the vortex flow in the valve body is disappeared, and the check valve operating conditions are more stable than before.