基于对冲能耗与多级流阻的调节阀减压控速机理研究

Study on pressure reduction and speed control mechanism of regulating valve based on energy consumption and multistage flow resistance

针对目前迷宫式、多级套筒式等调节阀在高温高压差工况下存在减压控速不平稳、空化严重等问题,提出了一种基于流体对冲能耗与多级流阻复合降压的空间转角蚁穴式多级调节阀,其关键节流元件内部流道由空间转角式多级流阻及对冲式流道两种结构组成,可实现对冲能耗及多级流阻的复合降压.对冲和转角处出现旋涡可进行能量耗散,流体经过一个减压级压力降低一个等级,实现了流体压力逐级降低.通过计算流体力学(CFD)流场仿真,分析了节流元件级间压力和速度随降压级数、不同压力等级的变化规律,仿真结果表明:采用该复合降压结构的对冲流道降压效率为单个转角降压(传统迷宫降压结构)效率的3倍,复合降压效率得到显著提高,采用多级流阻和流体对冲复合降压原理的节流元件在不同级数下均具有较好的线性平稳减压控速调节性能.最后搭建了实验测试平台,对不同降压级数的节流元件的级间压力进行了测试,实验结果与仿真结果具有较好的一致性,验证了理论分析的正确性.

At present,labyrinth and multi-stage sleeve control vales have problems such as unstable pressure reduction and speed control and serious cavitation under high temperature and high pressure differential conditions.An ant-hole multi-stage control valve was proposed based on the compound pressure reduction of fluid hedging energy consumption and multi-stage flow resistance.The throttling element inside the valve core was composed of space angle and opposed flow channel,which can realize the compound pressure reduction of opposed energy consumption and multi-stage angle flow resistance.The energy dissipation can be realized by the vortex at the hedge and corner,and the fluid pressure was reduced,realizing the gradual reduction of fluid pressure.Through computational fluid dynamics(CFD)simulation,the variation of inter-stage pressure and velocity of throttling element with step-down stages and different pressure levels were analyzed.The simulation results show that the depressurization efficiency of the counter flow passage with the composite depressurization structure is three times than that of the single corner depressurization(traditional labyrinth depressurization structure),and the composite depressurization efficiency is significantly improved.The throttle element,which adopts the multi-stage flow resistance and fluid hedge composite depressurization principle,has better linear and stable pressure reduction and speed control performance under different stages.Finally,a test platform is built to test the pressure of the throttling elements under different depressurization stages.The test results are in good agreement with the simulation results,which verifies the correctness of the theoretical analysis.