空蚀磨损翼型流场特性试验研究

在建立了能够模拟水力机械内部流动特征的翼型空蚀磨损试验装置后,针对翼型表面的流场流动特性进行试验研究.试验采用PIV系统对不同空化数下翼型表面不同断面流场进行大量图像采集,对无空化工况各断面计算其涡量流线及速度分布,对空化工况获取不同时刻翼型表面空穴结构.试验结果揭示了翼型表面涡量流线和速度分布以及其随空化数变化的特征,同时给出了翼型表面空穴结构周期性变化规律及原因,为开展翼型空蚀、磨损及两者联合作用提供了理论支持.

Experimental Study of the Flow Characteristic on the Surface of Hydrofoil for Cavitation and Silt Abrasion

After the establishment of the experimental apparatus for cavitation and silt abrasion of hydrofoil,the experimental study of the flow on the hydrofoil was performed.Large quantities of pictures were collected by PIV at different cavitation number.The distribution of vorticity,streamlines and velocity were calculated for all section without cavitation,and the cavitation structure at different time on the hydrofoil was acquired for the condition of cavitation.The experimental results displayed the characteristics of the variation of the vorticity and velocity on the surface of the hydrofoil at different cavitation number,and the reason which causes the periodic variation of the cavitation structure was analyzed.The result offers support for the study of cavitation,silt abrasion and their synergism.