本文应用数值模拟方法研究磁场作用下近壁圆柱绕流对金属流体流动传热性能的影响,揭示了磁场强度、加热板振幅、热流密度和间隙比（G/D）对流动结构和增强换热特性的作用机理。结果表明：洛伦兹力驱使圆柱尾涡向加热板迁移,随着磁场强度增强,圆柱后方涡脱落呈现先促进后抑制的变化特征,导致换热效率呈现先升后降的非单调变化。加热板振幅的增大会增强圆柱与加热板之间流体的速度扰动,使加热板温度边界层厚度减薄,从而显著提高换热效率。热流密度与G/D的改变会影响圆柱尾流结构与涡脱落模式,其中G/D增大时,换热效率受加热板与涡的相互作用呈现先增后减趋势。
This work investigates the flow of liquid metals around a near-wall cylinder and the enhancement of heat transfer under a magnetic field through numerical simulations. It analyzes the physical mechanisms of influence of the magnetic field, the amplitude of the vibrating plate, the heat flux and gap ratio(G/D) on flow structure and heat transfer. The results indicate that the Lorentz force drives the vortex toward the heated plate. As the magnetic field increases, the vortex shedding behind the cylinder exhibits a trend of initially promoting and then suppressing, resulting in a non-monotonic variation in heat transfer efficiency, which first increases and then decreases. Increasing the amplitude of the heated plate enhances the velocity disturbance between the cylinder and the plate, which reduces the thickness of the temperature boundary layer, thereby significantly improving the heat transfer. The changes in heat flux and gap ratio significantly impact the flow structures and the vortex shedding modes. When G/D increases, the heat transfer efficiency shows a trend of first increasing and then decreasing due to the interaction between the heated plate and the vortices.
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