变间距弧型除水器动力学特性研究

根据N-S方程组描述了冷却塔变间距弧型除水器内的气液两相流动,采用SSTk-ω模型及颗粒轨道模型对方程组进行封闭,针对除水效率建立了该类除水器的数学模型.通过调节结构参数（除水器板间距）和工况参数（气体流速、液滴直径）,对弧型除水器内多相流流场进行数值模拟计算,分析了各参数对变间距弧型除水器分离效率和压降的影响,提出了提高脱水率的可行性方案.研究发现：液滴直径越大,双通道的弧型除水器的除水效率越高;在低于临界流速的情况下,气速越大,分离效率越大,但达到临界速度以后,变化就不明显;相邻的两个折板间距越小,除水器除水效率越高.

Study on fluid-dynamics characteristics of variable-pitch sinusoidal drift eliminator

By describing the two phase flow in the cooling tower with the N-S equations set that closed through SST k-ω and particle-track model,a mathematical model was established for simulating the separation efficiency of variable-pitch sinusoidal drift eliminator.Via calculating the separation efficiencies of various demisters with different structural parameters（plate spacing） and varying operational parameters（gas flow rate and droplet size）,and analyzing their effect on efficiency and pressure drops,a general rule for separation efficiency is obtained.It is found that the separation efficiency increases with the droplet size.When the gas flow rate is lower than the threshold,the separation efficiency will increase with the gas velocity.However,when the gas flow rate is higher than the critical speed,the separation efficiency do not change significantly.The separation efficiency of smaller distance of sinusoidal drift eliminator is higher than the larger distance.