两同轴旋转圆台之间不可压缩流体的数值模拟

Numerical simulation of an incompressible fluid between two rotating coaxial frustum cones

本文主要研究了两同轴旋转圆台(外圆台固定)间流体的流动性质。结果表明:出口附近的流体在旋转开始后要向圆台上部回流,形成了一个压力和速度极大的涡流区域。该区域约位于z/h=0.05～0.30,并随着转速的增加而向圆台顶部移动。当转速较小时,流体速度沿径向呈线性关系;当转速较大时,线性关系变为近似二次函数的关系。随着圆台倾角变小,流动越来越容易失稳。最后通过与Taylor-Couette流进行的比较,发现圆台绕流更容易失稳。

The flow properties in the region between two coaxial frustum cones, with the inner one rotating and the outer one stationary, have been studied. It is shown that the fluid at the outlet does not flow out directly when the rotor is started, but rises upwards. This reflux generates a vortex area with a significant velocity magnitude and pressure. The area, between z/h = 0.05 and 0.30 rises upwards with increasing rotation speed. The velocity magnitude is linear in the radial direction if the rotation speed is small, but has a quasi-quadratic form at higher speeds. If the frustum cone inclination is small, the flow will tend to be unstable with significant velocity magnitude and pressure. It was found that this flow is much more unstable than Taylor-Couette flow.