Experimental test of heat transfer from transport casks with axial fins

n order to achieve higher heat dissipation, the outer surface area of the transport and storage cask for radioactive material is increased by the use of cooling fins. The GNB CASTOR® casks are fitted with cooling fins, machined into the cask body, which run circumferentially around the cask outer surface. The first generation GNB CONSTOR® casks have a smooth outer surface without fins which is made from a steel plate. This is possible because the heat capacity of their contents is relatively low. For higher heat capacities of the CONSTOR® cask, it is necessary to develop a special solution to allow heat to be dissipated from the cask´s outer surface. For the CASTOR® cask series, it is also desirable to achieve higher heat dissipation rates. From an economic point of view, a solution whereby separate cooling fins are attached to a smooth outer surface would be preferable to the currently machined fins. Several concept solutions are available to achieve this. One of the concepts has been investigated in detail. This concept comprises a series of aluminium profiles which are strapped to the smooth outer cask surface. This in effect provides a cask with axial fins. This solution also allows for the inclusion of moderator material within certain areas of the aluminium profiles.