Natural convection in a square cavity with a heat generating body: Entropy consideration

Conjugate heat transfer in a cavity is an important consideration with regard to cooling of micro-electronic equipment. In the present study, a heat transfer analysis of conditions taking place in a square cavity with a heat source, located in it, is carried out. The natural convection accompanying conduction heat transfer in the heat generating solid body is examined. Air or water are considered as the fluid in the cavity while steel substrate is considered as the heat generating solid body. The location of the solid is changed in the cavity to examine the cooling conditions. The entropy analysis of the system is carried out to determine the irreversibility ratio for each location of the solid body in the cavity. It is found that the heat transfer from the solid body surfaces increases where the surfaces facing the inlet and the exit of the cavity. The entropy generated attains the maximum value for air when the solid body is located at the center of the cavity; in which case, the irreversibility ratio reduces to a minimum value.