CFD Simulations for Thermal Qualification of a Radioactive Material Transport Cask

Radioactive material transport casks [type B(U)/B(M)] are generally employed for the transportation of radioactive material of significant activity. These casks generally employ lead as a shielding material from gamma radiation. Further, the casks must comply with strict standards to withstand the series of tests. One of the tests requires the cask to withstand the fully engulfing fire for about half an hour. As the material lead has a low melting point, it could be a concern from the shielding perspective. This paper presents the results of a 30-min fire test of a radioactive transportation cask exposed to various thermal qualification conditions. To this end, CFD simulations have been carried out with an environment temperature equivalent to that of a hydrocarbon fuel–air fire and a constant 800 °C. It is observed that during the hydrocarbon fuel–air fire test, the lead melted even before the completion of the test. Further, the aspects of Rayleigh convection and its influence on the melting process are discussed in this paper. Additionally, the molten lead is estimated for all cases by the end of the 30-min fire test. Finally, the current investigation details are discussed in comparison with the literature.