非全周开口滑阀压力分布测量研究

MEARSUREMENT ON PRESSURE DISTRIBUTION OF NON-CIRCULAR OPENING SPOOL VALVE

研制出阀套移动式液压阀压力分布及噪声测量试验装置,通过阀套的平移和转动依次测量一定阀口开度下节流槽及阀腔壁面的压力分布。阀套采用测压小孔大间距布置、液压力压紧、小间隙精密配合等保证可靠密封,由量块对阀心及阀套进行定位保证重复精度,同时结构上保证阀套的移动不影响阀内部流场。首次对节流槽中的压力分布进行了测量,并与流场仿真进行比较,两者吻合良好,分析了压力分布变化规律。装置的研制为揭示节流槽结构与噪声的关系提供了基础,对于建立具有节流槽的液压元件噪声评价准则具有重要的意义。

A novel test apparatus used to measure the pressure distribution of the non-circular opening spool is proposed. Thus the mechanism of the noise differences related to the different spools can be investigated. A method using this test apparatus is also developed to measure the pressure distributions on the grooves and the walls of return chamber. This method being developed is named as 'the method of the sleeve shift'. The key point of this method is to stop the leakage among these small holes. Several ways are introduced, which include the hydraulic force used to close the gaps between the sleeve and valve body, the expansion effect of the sleeve wall in the return chamber on the gaps between holes to minimize the internal leakage and a high requirement of small clearances between the body, the spool and the sleeve. The effect of this test apparatus on the flow field inside the valve is limited to the minimum to improve the accuracy of the method proposed. The experimental results are agreed well with the CFD results. The test apparatus and correspondence methods to measure the pressure distribution are easy to be standardized and used for other hydraulic components with the grooves.