An Investigation of a Tunable Magnetomechanical Thermal Switch

Abstract

We propose a new device-level concept for a thermal switch that exploits the temperature dependence of the magnetization of a ferromagnetic material oscillating between a hot and a cold surface. A numerical model is constructed to examine the operation of the thermal switch. The switch turn-on temperature can be readily tuned by adjusting physical parameters of the device, such as the gap between the hot and cold surfaces and the spring constant of the structure supporting the ferromagnet. Experimentally determined oscillation frequencies are consistent with the model predictions. Additionally, it is shown that the thermal contact conductance has a large influence on the device performance. The time-averaged heat flux and effective conductance compare favorably to existing thermal switch technologies over a range of hot surface temperatures.