Simulation of Thermal Sensor for Thermal Control of a Satellite using COMSOL

G. Mangalgiri
BITS Pilani
Zuarinagar, Goa

Spacecrafts have a prime necessity that their temperature be controlled. This paper presents the simulation of a mechanically actuated field effect transistor that is used in a thermal system. It comprises of a composite beam, a piezoelectric substrate and a field effect transistor. The temperature rise causes a deflection in the composite beam thereby causing it to impinge on the piezoelectric crystal, generating voltage.

This mechanism is simulated using COMSOL Multiphysics. The simulation gives stress distribution of beam, peizoelectric crystal and variation of potential across the MOSFET. The actuator is especially useful for small sized satellites which have low thermal capacity. A sensitive mechanism as above enables the detection of the infinitesimal temperature change which is very beneficial for practical use.