换向滑阀组合节流槽流量系数研究

A Study on Flow Coefficient of Combined Throttling Groove in Spool Valves

针对换向滑阀设计过程中组合节流槽流量系数的复杂性与动态性问题,提出了换向滑阀组合节流槽流量系数的近似表达方法。研究以换向滑阀3种典型节流槽结构(圆型、U型及半圆型)的组合为对象,在确认三维流场解析与台架实验结果基本一致的前提下,引入极限饱和度概念,定量化地描述当前流量远离饱和流量的程度,推导出其流量系数的极限饱和度表达;在节流槽结构组合的有限变量空间内,以正交仿真实验分析变量空间内流量系数的变化规律,构建并标定其有限变量空间流量系数的近似模型。仿真结果表明,近似模型的标定误差最大值为5.27%,样本检验误差不超过5%,该方法有效地实现了对换向滑阀组合节流槽流量系数的近似表达,对此类结构设计具有工程应用价值。

A method to approximately express flow coefficient for combined throttle of spool is proposed to deal with the complexity and dynamic problem of flow coefficient of combined throttle in spool valve design.Combinations of three typical throttle structures(round, U and semicircular)are studied.A concept of limit saturation is introduced on the premise that the three-dimensional flow field analysis and bench test results are basically consistent.The limit saturation expression of the flow coefficient is deduced and the difference of the current flow from the saturated flow is quantitatively described.The variation law of the flow coefficient is analyzed in the finite variables space of combinations of the throttle structure using orthogonal simulation test,and an approximate model of the finite variable spatial flow coefficient is constructed and calibrated.Simulation results show that the maximum error of the approximation model is 5.27%while the sample error is not more than 5%.This result indicates that the proposed method effectively realizes the approximate expression of the flow coefficient of the combined throttle spool valve,and the method has engineering application value for such structural designs.