(An) analytical model for solid spot thermal conductance of nuclear fuel pellet-cladding interfaces

Abstract

An analytical model to predict solid spot thermal conductance of nuclear fuel pellet-cladding interfaces is developed. In the present model it is assumed that the contact spots are uniformly distributed over the entire apparent contact area by considering the controlling surface. It is assumed also that the contact spots are all circular and of identical radius, and that the deformation mode at the contact spots is plastic. The temperature distribution at the contact spots is analyzed with the equivalent heat channel. The solid spot conductance predictions made by the present model are then compared with the predictions of the existing models developed by the various authors and the available experimental data obtained by Rapier et al., by Dean, by Garnier and Begej. Good agreement is found between the predictions of the present model and these experimental data.