阀芯结构对节流截止阀流阻特性和内部流动特性的影响

Influence of Valve Core Structure on Flow Resistance Characteristics and Internal Flow Field of Throttling Stop Valve

为探索阀芯结构对节流截止阀性能的影响,基于有限体积法和标准k-ε湍流模型,在不同开度条件下,采用数值模拟的方法,研究平底、梯形和弧形三种不同阀芯结构节流截止阀的流阻特性,分析阀内部的速度和压力分布规律;并对三种阀芯结构的节流截止阀的流阻特性开展水力试验研究,数值模拟得到的阀门流量系数和流阻系数的结果与水力试验结果比较吻合。结果表明,在开度小于40%时,梯形和弧形阀芯结构的阀门较平底阀芯结构的阀门内部低压回流区有所减弱,压力分布趋于均匀,阀门流阻系数减小,更有利于阀门内部流体的流通;当开度大于55%时,三种阀芯结构的阀门流阻系数基本重合,并趋近与零;在整个开度,弧形阀芯结构的阀门流量随阀门开度变化较为均匀,更有利于阀门流量的调节。

To study the influence of valve core structure on throttling stop valve, the numerical simulation of flow field in the valve with flat bottom, Trapezoid and Arc valve core structure under different valve opening are computed based on finite volume method and standard k-ε turbulence model. The speed and pressure distribution in valve are analyzed. And hydraulic experimental test is carried out to obtain flow resistance characteristics. The flow coefficient and flow resistance coefficient of numerical methods basically agree with ones of hydraulic experiment. The results show that the low-pressure backflow area in valve with Trapezoid valve core and arc valve core are decreased, the pressure distribution tends to be uniform, and the flow resistance coefficient decreases when the opening is less than 40%. It is more conducive for the fluid through the valve. When the opening is more than 55%, valve flow resistance coefficient of three throttling stop valve close to zero are basically the same. For all opening, the flow of valve with Arc valve core is more uniformity and it has better control performance.