Computational modeling and analysis of thermal characteristics of a rotating spacecraft subjected to solar radiation

Abstract

Mohamed A. Gadalla and Essam WahbaCollege of Engineering, Mechanical Engineering DepartmentAmerican University of Sharjah, Sharjah 26666, U. A. E.This paper presents a computational modeling for the temperature distributionof a rotating thick-walled cylindrical spacecraft subjected to solar radiation. The innersurface of the spacecraft is thermally insulated while the outer surface is subjected toconcurrent events of solar incidence and radiative heat dissipation to space. Thegoverning equation for the normalized temperature is discretized using a finitedifference scheme and Successive Line Over-Relaxation (SLOR) is used to solve theresulting system of algebraic equations. Numerical simulations of temperature distri-bution on the spacecraft for different spinning speeds, angular positions, and differentradii are discussed and evaluated for both linearized and nonlinear boundary condi-tions. Comparative analysis between the computational modeling and the exactanalytical solution for the linearized boundary condition is presented. The resultsindicate that the outer surface temperature distribution of the spacecraft is nearlyindependent of the angular position; at sub-cylindrical surface, this independence isachieved at low angular velocity. Moreover, numerical simulations show that the useof the linearized boundary condition at the outer surface presents a good approximationfor the case of high-speed spinning spacecrafts, while it results in significant errors inthe temperature field in the case of stationary and low-speed spinning spacecrafts.© 2011 Wiley Periodicals, Inc. Heat Trans Asian Res, 40(7), 655–676, 2011; Publish-ed online 21 July 2011 in Wiley Online Library (wileyonlinelibrary.com/journal/htj).DOI 10.1002/htj.20368