基于CFD的尾水冷却器布置方案优化

为解决水电站二次循环技术供水冷却器传统布置方案存在的依赖工程经验、检修困难和降低水轮机效率等问题,通过对尾水渠三维流动定常数值模拟,提出了一种基于计算流体力学(CFD)的尾水冷却器布置优化方法。通过对模拟结果中尾水管上方平台拟安装冷却器区域内流场的流线、流速、湍动能等多个物理量的空间分布特性进行分析,选定来流速度较大的位置安装冷却器,建立了考虑实际冷却器几何模型的复杂尾水渠三维流动域模型进行数值模拟校核,以验证该布置方案的合理性。模拟及校核结果表明,此方案不仅满足冷却器的散热要求,同时便于检修和能避免对机组运行产生影响。

CFD-based optimization of layout scheme of tail water cooler

In order to solve the defects of relying on the engineering experience, difficult maintenance and reducing the efficiency of the turbine in the traditional layout scheme of the water supply cooler in the secondary circulation technology of the hydropower station, this paper proposes an optimization method for the layout scheme of tail water coolers based on computational fluid dynamics(CFD) through the steady-state numerical simulation of three-dimensional flow in the tailrace. By analyzing the spatial distribution characteristics of multiple physical quantities such as streamlines, flow velocity, turbulent kinetic energy and other physical quantities of the flow field in the area where the cooler is to be installed on the platform above the draft tube in the simulation results, the location with a higher flow velocity from the cooler is selected as the appropriate installation position. The three-dimensional flow domain of the complex tailrace channel considering the geometric model of the actual cooler is established for the numerical simulation and verification to check the rationality of the layout. The simulation and verification results show that this scheme not only meets the cooling requirements of the cooler, but also facilitates the maintenance and avoids any impact on the operation of the unit.