挖掘机虚拟载荷下换向阀开启过程的液动力分析

为了提高换向阀开启过程的换向性能,以降低该过程的液动力为目标,提出液压挖掘机虚拟载荷下开启过程的阀芯结构形态设计方法:以液压挖掘机整机动态性能试验数据为基础,将其作业的周期性、随机性载荷特征抽象为具有统计特性的虚拟载荷;再以虚拟载荷为边界条件,以降低开启过程阀芯所受液动力为评价标准,分析不同阀芯结构形态的流固耦合动力学响应,探讨换向阀阀芯结构优化设计方法.结果表明,合理等效阀口面积的U型槽结构可有效降低不同虚拟载荷下的阀芯液动力.

Analysis of Flow Forces During Muti-valve ' s Opening Under Excavator Virtual Load

To improve the muti-valve’s commutation ability and to reduce the valve’s flow forces during its opening， the valve structure of a hydraulic excavator under virtual loads was designed. First， the excavator virtual load model was established based on the excavator dynamic test data， and the statistics were used to express the load’s periodic and random characteristics. Then， a 3D valve model with the boundary conditions of virtual load was proposed to solve the flow forces during the valve’s opening using the fluid structure interaction method. Finally， the flow force response characteristics of different valve spool structures were presented by the model. The results show that the spool with U-groove of moderate equivalent valve orifice area can effectively reduce the flow force under a series of virtual loads.