陡坡后消力池内水跃的数值模拟

Turbulence model of hydraulic jump in a post-steep plunge pool

利用三维RNG k-ε紊流模型和体积率(VOF)跟踪自由水面的方法,对4种不同工况、相同坡角的陡坡后消力池内的水跃特性进行了数值模拟,并与模型试验结果进行了对比.结果表明,不同工况下消力池内水面线特征、流速和水跃长度与模型试验吻合较好,陡坡后消力池内淹没水跃长度大于自由临界水跃长度.同时,数值计算与试验结果均表明,陡坡后消力池内水跃长度不能按照平底矩形水跃长度计算公式进行计算,必须考虑淹没度的影响,从而有效避免陡坡后消力池设计中的不足.

Using a three-dimensional RNG k-ε turbulence model and the method of the volume rate（VOF） to track free water surface,the hydraulic jump characteristics of a plunge pool behind the steep slope with the same slope angle are simulated under 4 different working conditions in this study.By comparing the simulated results with the model test results,we find that the feature of water surface profile,velocity and length of the hydraulic jump agree well with each other,and the length of submerged hydraulic jump is greater than that of free critical hydraulic jump in the plunge pool behind the steep slope.The numerical calculation and the test results indicate that the length of the hydraulic jump in the plunge pool behind the steep slope can not be calculated by a formula used in flat bottom rectangular hydraulic jump,and the influence of submergence degree must be considered to avoid the designing deficiency of the plunge pool behind the steep slope.