Design and analysis of a micro-satellite passive thermal control system using determinants and FEM methods

In this paper thermal design and analysis of a micro-satellite with two different methods will be discussed. These are Determinants and Finite Element Method using ANSYS software. Considering orbital position and attitude of spacecraft, different heat fluxes exerted on each surface of spacecraft will be calculated. These heat fluxes are : sun direct heat flux, earth IR heat flux and Albedo heat flux which is the reflected portion of sun heat flux by the earth. Using these heat fluxes as transient boundary condition for heat transfer equation, and solving it in mixed conduction-radiation transient mode with two methods mentioned above, the temperature distribution variations of each internal unit of spacecraft is obtained. The comparison of two methods shows a good agreement within the results. Comparing these results with thermal requirements and constraints of all units and performing some trail and error, the final thermal design has been obtained. (author)