Based on a prospect of steady increase in the amount of spent fuel, it is expected to establish large capacity dry storage technologies for spent fuel. This report describes the result of the heat removal test of a cask storage system using a 1/5 scale model.
Cooling air induced by the natural convection strongly streamed along the floor from inlet to the center of the storage area, and the velocity gradually reduced as the stream reached to the center. On the other hand, upward flow induced by the buoyant force was observed in the boundary layer close to the surface of the cask models. On the feature of this flow pattern, heat transfer coefficient around cask models was expressed with a high degree of accuracy, in which the effect of horizontal stream was introduced in addition to that of the upward flow. Moreover, the effects of heat generation, geometrical arrangement of cask models, etc. On heat removal performance were made clear as a result of parametric tests. And in conclusion, velocity and temperature distributions in the assumed actual cask storage facility were evaluated in consideration of the similarity law applied to this test.
