冷却塔折流板除雾器叶片折角优化数值模拟

Impact of Bend Angle on Removal Efficiency of Cooling Tower Wave-plate Mist Eliminator by Numerical Simulation

为探究冷却塔折流板除雾器不同物理参数(叶片转折角度、气流流速、液滴粒径等)与除雾效率的关系,本文采用SST k-ω模型和Euler/Lagrange方法对梯形折流板除雾器内气液两相流动进行二维数值模拟。结果表明,折流板除雾器对粒径小于10μm的液滴除雾效率较低;随着叶片转折角度的减小,折流板除雾器的除雾效率和压降均有所上升;对于本文研究的不同结构的折流板,当除雾器的效率相同时,叶片折角为α=45°的除雾器所需的功耗最低,是最佳选择。在实际工程应用中,折流板的选取应对除雾效率与气流压降进行综合考虑。

This paper numerically investigates the relationship between removal efficiency and various parameters of cooling tower wave-plate mist eliminator,i.e.,bend angle(α),gas velocity and droplet diameter,2D numerical simulation was carried out on the gas-liquid two-phase flow in the trapezoidal wave-plate mist eliminator by using SST k-ωmodel and Euler/Lagrange method.The results show that,for droplets with diameter less than 10μm,the removal efficiency of the wave-plate mist eliminator was relatively low.Moreover,both the removal efficiency and pressure drop of the mist eliminator increased somewhat with decrease of the bend angle.For the wave-plates of different constructions in present study,when the removal efficiencies of mist eliminators are the same,the power consumption required by the mist eliminator with the bend angle ofα=45°is lowest and is the best choice.In the practical engineering applications,comprehensive consideration should be given to both the removal efficiency and pressure drop in the selection of wave-plates.