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为进一步研究突扩突跌体型的脉动压力和空蚀破坏,用三峡泄洪深孔突扩突跌掺气水工模型对侧墙和底板的水流脉动压力进行了详细量测,建立了压力脉动强度σ与壁面剪切应力的关系式。给出了侧墙和底板脉动压力强度系数K的表达式;侧墙冲击点处脉动压强偏离正态分布,底板脉压幅值是时均压力的35%~50%。通过时间积分比尺TE和空间积分比尺Lf的分析,发现侧墙冲击点处的TE值较大,相应的Lf值也较大,冲击点下游TE和Lf很快变小,其规律与频谱分析一致。水流冲击底板处,主频带窄,脉动压力强度大,时间积分比尺值和纵向积分长度比尺也较大。
In order to further study the pulsating pressure and cavitation damage of sudden protrusion and plunging body, the fluctuating pressure of water flow in the side wall and the bottom plate was measured in detail by using sudden expansion and aeration aeration hydraulic model of the Three Gorges Flood Diversion Project. Pressure pulsation intensity Relationship between σ and wall shear stress. The expression of pulsating pressure intensity coefficient K on the side wall and the floor is given. The pulsating pressure at the impact point of the side wall deviates from the normal distribution, and the amplitude of the floor pulse pressure is 35% ~ 50% of the mean pressure. Through the analysis of the time integral scale TE and the spatial integral scale Lf, it is found that the TE value at the impact point of the side wall is larger and the corresponding Lf value is also larger, and TE and Lf in the downstream of the impact point quickly decrease. The law and frequency spectrum Analysis of the same. Water impact at the bottom plate, the main frequency band narrow, pulsating pressure intensity, time integral ratio scale and longitudinal integral length scale is also larger.