绕圆柱体自由表面磁流体流动和传热的研究

SIMULATION OF FREE SURFACE MHD-FLOW AND HEAT TRANSFER AROUND A CYLINDER

本文对在不同雷诺数下,绕圆柱体的磁流体自由表面流动及传热进行了模拟,分析了磁场对绕流圆柱尾迹和涡分离的影响,获得了两种雷诺数下的电磁力密度、流场和温度场分布。结果表明,磁场不仅影响了流动的形态,而且对湍流有抑制作用,降低了自由表面的更新机制,从而减少了传热能力;在相同的Hartmann数下,相比低雷诺数下的流动换热情况,高雷诺数下的湍流不能被完全抑制,自由表面与尾迹的相互作用也较强,因而自由表面换热也较强。

Magnetohydrodynamic （MHD） free-surface-flow of liquid mental around a cylinder under different Reynolds numbers was simulated numerically. The effect of magnetic field on wake and vortex shedding were analyzed. The flow fields and temperature as well as Lorentz force under two different Reynolds numbers were presented. The results show that magnetic field can change the flow pattern, suppress turbulent viscosity and surface renewal, which degrade heat transfer. Under same Hartmann number, turbulent intensity and interaction between free surface and wake are still stronger compared with that case of lower Reynolds number, consequently, the heat transfer is well still.