A quasi transient heat conduction model of heat transfer in fuel-coolant interaction in LMFBRs

In this paper, we have studied the effect of fuel temperature profile, that builds up in the fuel particles during the transient heat conduction from fuel to the coolant in the mixing zone of molten fuel-coolant interaction (MFCI) in LMFBRs, on the thermal to mechanical work energy conversion efficiency. The results have been compared with the transient heat conduction model of Cho, Ivins and Wright who assumed a linear fuel temperature profile over the fuel particles during the transient. It has been found that whereas the linear fuel temperature profile model of Cho et al. and the present model give almost similar results for smaller fuel particles with radius less than 10 μ, the results of these two models differ for bigger fuel particles. Hence, the present model of quasi-transient heat conduction which is an improvement over the linear temperature profile approximation of Cho et al. may be used when the fuel particles interacting with the cold sodium are of coarse size. (orig.)