Fission gas venting from liquid cooled reactor element - by simple expansion chamber and stand pipe common to all rods

摘要

A fuel element, breeder element or absorber element intended to be mounted vertically when in use in a reactor comprises a individual rods of these materials parallel to the axis and an expansion chamber for fission gas operating on the immersed bell (or immersed cone) principle. This expansion chamber is common to all the rods and has a single standpipe, open to the interior of the expansion chamber and communicating with the surrounding liquid coolant. Liquid coolant initially contained in the expansion chamber can thus be progressively driven out through the standpipe into the reactor cavity. The expansion chamber may be either below the rods or partly above and partly amongst them. Used in a liquid-cooled nuclear reactor. By having a single standpipe, the gas is transported to the liquid coolant without causing bubbles and consequent hot spots on the heat transfer surfaces.