矩形圆弧角养殖池系统固液两相流数值模型的构建与进径比影响研究

Numerical Model Construction of Solid-Liquid Two-Phase Flow and Influence of the Relative Inflow Distance in Rectangular Circular Angle Aquaculture Tank

为研究单通道排污的矩形圆弧角养殖池系统集排污性能,采用RNG k-ε湍流模型与DPM模型相结合的方式建立固-液两相流动的数值计算模型。在试验验证的基础上开展单管入流模式下,进径比(参数C/B,C是射流孔位置到养殖池壁的水平距离,B是养殖池短边边长)对单通道排污的养殖池系统内沉降式固体颗粒物的汇集规律和排出效率进行研究。结果表明,养殖池系统的集排污性能与养殖池内尤其是池底的流场条件密切相关。基于进径比参数C/B的调整可优化池内及池底的流场条件,进而提高养殖池系统的集排污性能。研究表明,进径比参数C/B=0.03时,即有利于养殖池系统获得最佳流场条件又可明显提高养殖池系统的集排污性能,对工厂化循环水养殖系统构建具有重要价值。

In order to study the sewage collection performance of rectangular circular arc angle aquaculture tank with single channel sewage,a numerical model of solid-liquid two-phase flow was established by combining RNG k-εturbulence model with DPM model.Through comparative study,the cumulative discharge rate of solid particles is highly consistent with the results of physical model test.Based on the validation of the numerical model,the influence of the relative inflow distance(C/B,C is the horizontal distance from the jet hole to the tank wall,B is the length of the short side of the tank)on the collection rule and discharge efficiency of the settling solid particles in the single channel sewage aquaculture tank was studied.The results show that the collection and discharge performance of aquaculture tank is closely related to the flow field conditions in the tank;the collection and discharge performance of aquaculture tank is not only related to the flow field velocity,but also closely related to the flow field uniformity of the system and the strength of high-speed vortex zone in the center of the tank.Based on the adjustment of inlet diameter ratio parameter C/B,the flow field conditions inside and at the bottom of the tank can be optimized,and the collection and discharge performance of the tank can be improved.The results show that when the inlet diameter ratio parameter C/B=0.03,it is not only conducive to obtain the best flow field conditions,but also can significantly improve the sewage collection performance of the aquaculture system,which has important value for the construction of industrial recirculating aquaculture system.