Compact integrated electromagnetic driving of liquid metal for high heat-flux dissipation

Abstract

Liquid metal (LM) has been widely utilized in scenarios involving overloaded thermal energy delivery and high heat flux thermal management due to its excellent thermal properties. However, the high-performance driving method limits LM-based thermal management. In this paper, a compact integrated rotating permanent magnet induction electromagnetic pump (PM-EMP) is developed for LM. In addition, a three-dimensional multi-physical field numerical method and accurate analytical prediction correlation are built to optimize PM-EMP performance. We systematically investigate the magnetohydrodynamic generation process and factors influencing performance. The results demonstrate that optimizing electromagnetic parameters significantly weakens non-sinusoidal distribution, thereby promoting high output characteristics and flow stability in PM-EMP. By binding the tangential component within the short-circuit strip, we enhance and uniformly distribute the vertical component of current density along channel width, improving current density by 110 %. This optimization facilitates near-wall current distribution to suppress lateral end effects. Notably, strengthening magnetic flux and current density distribution/intensity reduces local pressure pulsation, thus enhancing driving characteristics and flow stability. Considering the influence of lateral end effect and geometric parameters, the performance prediction accuracy obtained by modified analytical correlation can achieve more than 90 % improvement by 28.9 %. Furthermore, we validate the effectiveness of theoretical methods by prototype performance testing.