沉割槽对滑阀阀芯径向卡紧力的影响
Effects of Cutting Groove on Radial Clamping Force of a Slide Valve’s Spoo

针对液压滑阀阀体沉割槽内液体流速不同会产生径向卡紧力的问题,利用CFD软件对某滑阀沉割槽处阀芯台肩所受径向压力分布进行研究,同时,根据滑阀内部流道的结构特点,结合理想流体伯努利方程,建立了沉割槽处阀芯台肩上压力分布的数学模型,并且通过实验验证了模型的准确性,分析了沉割槽尺寸及流量对阀芯径向压力分布的影响。研究表明:阀芯台肩上径向压力分布不均匀,且压力值随入口流量、沉割槽深度和宽度呈二次多项式函数关系上升;随压力点位置从远离出口位置至靠近出口呈平方关系下降;当阀口开度为0？？5 mm、流量为40 L/min时阀芯台肩径向卡紧力为4？？2 N,是流量为10 L/min情况下的16倍,且沉割槽深度减半后,卡紧力增至14？？47 N。最后,提出了一种偏心沉割槽结构,仿真结果表明,入口流量大于40 L/min时,偏心沉割槽结构中径向压力分布的不均匀度比传统同心结构提高了64％以上,有效降低阀芯径向卡紧力。
The radial force distribution of the spool is analyzed using computational fluid dynamics’ software to solve the problem that radial clamping force is generated on the shoulder of the valve spool for the difference in flow velocity around the groove because of the existence of the cutting groove in the house of slide valve. A mathematical model of the pressure distribution is derived based on the inner flow channel structure of the slide valve with combination of the ideal fluid’s Bernoulli equation and the accuracy of the model is verified by experiments. The results show that the radial pressure distribution on the spool shoulder is uneven, and the valve increases in quadratic polynomial form with the groove’s depth, width, and inlet flow rate, while a decrease in square relation with the distance from the position to the exit port. The radial clamping force on the spool shoulder is 4？？2 N when the inlet flow is 40 L/min and valve opening is 0？？5 mm, which is 16 times larger than the value under 10 L/min. The force increases to 14？？47 N when the depth of the groove is halved. Finally, an eccentric groove structure is proposed, and simulation results show that the structure reduces unevenness of the radial pressure on the spool by more than 64％ when the flow is larger than 40 L/min, and effectively reduces the radial clamping force of the spool