高压降迷宫套筒组合调节阀涡激振动仿真研究

针对高压降类调节阀涡激振动现象,设计多通道迷宫盘片和多级套筒组合高压降调节阀。基于计算流体动力学(CFD)和流固耦合模态分析法,计算调节阀内部瞬态流场及结构模态,得到其三种典型开度的流体流动情况,升力系数时域和频域特性曲线,以及模态频率和模态振型。分析结果表明:4s时刻,随调节阀开度减小,流体最大流速相应减小,第四级套筒外部流道区域的大涡逐渐形成小涡。调节阀全开时流体升力系数波动比70%和40%开度时更为剧烈,一阶模态频率、二阶模态频率均随开度的增大而增大。调节阀模态频率没有落在漩涡脱落主频率范围内,调节阀不会发生涡激振动锁定现象。

Simulation for VIV of high pressure drop labyrinth-sleeve combined regulating valves

Aiming at vortex-induced vibration (VIV) phenomena of high pressure drop type regulating valves, a high pressure drop regulating valve with combination of multi-channel labyrinth discs and multi-stage sleeves was designed.Based on CFD and the fluid-structure coupled modal analysis, inner transient flow field and structural modes of the valve were calculated to obtain its 3 typical open fluid flow cases, lift coefficient’s time domain and frequency domain characteristic curves as well as modal frequencies and modal shapes.The results showed that at 4 s time instant, with decrease in the valve’s opening, the maximum flow velocity of fluid decreases, and large vortex in outer flow channel of the fourth-stage sleeve gradually forms small one; fluctuation of fluid lift coefficient during the valve being fully open is more violent than those during the valve having 70% and 40% openings, the 1st and 2nd order modal frequencies of the valve increase with increase in valve opening; the valve’s modal frequencies don’t fall in range of vortex shedding main frequency, the valve can’t have VIV locking phenomenon.