平底水垫塘透水底板下表面脉动压力试验研究

Experimental investigation of fluctuating pressure acting on the undersurface of pervious slabs in flat-bottom plunge pool

基于模型试验结果,研究了平底水垫塘透水底板下表面的脉动压力特性,分析了不透水底板及透水底板不同开孔率情况下的下表面脉动压力的分布规律、概率特性以及互相关特性和频谱特性。分析结果表明:在水舌冲击区,脉动压强系数随着开孔率的增大而增大;互相关系数随着开孔率的增加而略有减小,其旋涡保持性有所降低;透水底板较不透水底板下表面的脉动能量更加集中于低频。

Based on the model test results,the characteristics of fluctuating pressure acting on the undersurface of the pervious slab in plunge pool were investigated and the distribution law,the probability characteristics,the cross correlation characteristics and the spectrum characteristics of fluctuating pressure were analyzed for both the impervious slabs and pervious slabs with different aperture ratios in the flat-bottom plunge pool. The analysis results show that in the impacted area fluctuating pressure intensity coefficient increases with the increase of pervious coefficient,the correlation coefficient slightly reduces as the pervious coefficient increases,which shows that the flow eddies retentivity reduces. Comparing with the impervious slabs,the pressure fluctuation energy of pervious slabs is more concentrated on low frequency section. The relations between the pervious coefficient（k） and fluctuating pressure acting on the undersurface of the pervious slab are established.