自吸式搅拌槽内流动特性的数值研究

Numerical Simulation of Fluidity in Self-priming Tank

采用计算流体动力学方法对自吸式搅拌槽内流体流动进行数值研究,分析气体分散通道的叶片角度、下层桨的形式和桨叶的间距对槽内流动场的影响。研究结果表明:当气体分散通道叶片角度较小时,上层桨产生的径向射流能够沿着切线方向流经气体分散通道,在气体分散通道出口处形成的漩涡范围较小;当下层桨为PDTU时,旋转桨叶在排出流体的同时,对流体有上扬作用,两层桨之间的轴向作用较强,有利于整个搅拌槽的混合;桨叶间距较大时,两层桨之间的轴向作用较弱,下层桨的泵送能力降低,功率消耗增加。

The fluid of the self-priming tank is simulated by using the computational fluid dynamics method,and the influence of the blade angles of the gas dispersion channel,the types of the lower impeller and the impeller spacing on the flow field in the tank are analyzed.The results show that when the impeller angles of the gas dispersion channel is smaller,the radial jet caused by the upper impeller can flow through the gas dispersion channel along the tangential direction,and the vortex that forms at the outlet of the gas dispersion channel is smaller.When the lower impeller is PDTU,the rotating impeller has an upward effect on the fluid while discharging the fluid,and the axial force between the two layers of impellers is stronger,which is beneficial to the mixture of the whole tank.When the impeller spacing is larger,the axial force between the two layers of impellers is weaker,the pump power of the lower impeller reduces and the power consumption increases.