A long cylindrical black surface fuel rod of diameter 25 mm is shielded by a surface conce...

A long cylindrical black surface fuel rod of diameter 25 mm is shielded by a surface concentric to the rod. The shield has diameter of 50 mm and a constant surface temperature of 320 K. Both inner and outer surfaces of the shield have an emissivity of 0.05, and the gap between the fuel rod and the shield is a vacuum. If the fuel rod is generating 0.5 MW/m3 of heat per unit length, determine the surface temperature of the fuel rod.