Heat Transfer Characteristics of a Nuclear Foe! Element Cooled in a Surrounding Medium

摘要

This paper deals with the thermal design aspects of a rectangular nuclear fuel element dissipating fission heat in a surrounding medium. Considering average heat transfer coefficient over its surface, at first, the validity of one-dimensional model is examined. Next, various critical parameters, which govern the thermal design of the two-dimensional model are obtained. While the solution of one-dimensional model is obtained analytically, second order finite difference schemes are employed to solve the equation governing the two-dimensional model. The results are presented for a wide range of aspect ratio, A{sub}n Biot number Bi and heat generation parameter Q. It is concluded that for A{sub}r ≥7.0, Bi and Q being kept fixed; one-dimensional model prediction is quite satisfactory. Further, it is concluded that there exist the critical values of the parameters above or below which the temperature of the fuel element crosses its allowable limit.