水利水电技术2018，Vol.49Issue(4)：70-75,6.DOI:10.13928/j.cnki.wrahe.2018.04.011
水垫塘冲击区掺气浓度对脉动压强作用的试验研究
Experimental study on effect of aeration concentration on fluctuating pressure in impacted region of plunge pool
摘要
Abstract
The effect of the aeration concentration on fluctuating pressure in the impacted region of plunge pool after water flow being discharged into plunge pool is studied herein with hydraulic model experiment;from which the effects of various aeration concentrations on the fluctuating pressure of the bottom slab in the impacted region of plunge pool are studied through making the aeration concentration of the water body in the plunge pool changed by changing the amount of aeration.The result of the data analysis shows that under the condition of keeping the water cushion depth and the discharge-flow rate unchanged,the value of aeration concentration of water body at a same measuring point in the impacted region of plunge pool is to be increased along with the increase of the amount of aeration through increasing amount of aeration.The distribution law of the aeration concentration in the impacted region of plunge pool is that the aeration concentration reaches to its maximum value at the impacted point and then gradually decreases toward the upstream and the downstream of the impacted point,while the peak value of the total dynamic water pressure on the bottom slab of the impacted region is to be decreased along with the increase of amount of aeration and the variance of the fluctuating pressure is reduced along with the increase of amount of aeration,i.e.the fluctuation amplitude is decreased.The distribution of the probability density of the fluctuating pressure is a normal distribution,while its distribution curve is to be steepened and narrowed along with the increase of amount of aeration and the distribution of the fluctuation intensity coefficient is concentrated,i.e.the variance is decreased with the decreased peak value of pressure and the decreased fluctuation intensity.The law of the fluctuating pressure spectrum distribution at the same measuring point is consistent,of which the dominant frequency is concentrated in a low frequency range and the fluctuation amplitude decreases along with the increase of amount of aeration,i.e.the fluctuating pressure is decreased.关键词
水垫塘/掺气浓度/脉动压强/概率密度/频谱特性Key words
plunge pool/aeration concentration/fluctuating pressure/probability density/spectrum characteristic分类
水利科学引用本文复制引用
马文韬,杨红宣,张功育,赵伟,王海军..水垫塘冲击区掺气浓度对脉动压强作用的试验研究[J].水利水电技术,2018,49(4):70-75,6.基金项目
国家自然科学基金项目“高坝泄洪消能不同水流结构下气体迁移扩散运动机理研究”(51669007) （51669007）
