基于三维CFD方法的排水头部温排水扩散模拟研究

Numerical investigation and optimization on thermal discharge interactions between drainage heads using three-dimensional CFD method

热电厂温排水对环境和水生生物的影响较大,因此温排水扩散研究对于确定热电厂的设计参数至关重要。文章开展了三维CFD数值模拟,研究了排水头部温排水局部流场特征,探讨了不同蘑菇头直径、高度和间距对温排水相互作用的影响。研究发现:蘑菇头直径越大,高度越高,排水速度越低,温排水之间的相互影响越小,流场结构越简单。当排水速度较高时,侧向高速射流引起强烈流向漩涡,导致排水头部下游床面附近产生高温升区,不利于温排水的扩散。4℃温升区域面积随着蘑菇头高度的增加而降低。蘑菇头的参数优化宜遵循大直径、大高度和低排水流速的原则,在此基础上可适当减小蘑菇头的间距。

The impact of power plants′thermal discharge on the environment and aquatic life is significant,making the study of thermal discharge diffusion critical for determining the design parameters of power plants.Three-dimensional CFD simulations were carried out to study the local flow features of the thermal discharge of drainage heads.The effects of different drainage head diameters,heights,and spacings on the interaction of thermal discharge were investigated.It was found that a larger drainage head diameter and height and a lower drainage velocity undermine the interactions of thermal discharge,leading to simpler flow structures.When the drainage velocity is high,the lateral high-speed jet flow causes strong streamwise vortices,resulting in a high-temperature region near the seabed downstream of the drainage heads,which is unfavorable for the fast diffusion of thermal discharge.The area of the 4℃temperature-raise region decreases with the increasing drainage head height.The optimization of drainage head parameters should follow the principles of large head diameter,large head height,and low drainage velocity.On this basis,the spacing between drainage heads can be appropriately reduced.