GB958684A - Improvements in or relating to fuel elements for nuclear reactors - Google Patents

Abstract

958,684. Nuclear fuel elements. UNITED KINGDOM ATOMIC ENERGY AUTHORITY. Oct. 5, 1961 [Oct. 10, 1960], No. 34657/60. Heading G6C. The sheath 2 enclosing the fuel member 1 of a nuclear fuel element is provided with helical heat transfer fins 3 and longitudinal splitter fins 4, the latter possessing axial and radial asymmetry so that, when coolant gas flows lengthwise of the element, lateral stabilising forces are applied to the element. In the example illustrated, there are four equi-spaced longitudinal splitter fins 4, one being of simple fin form, one having an L-section outer region 8 for one-third of its length from the top with the remainder of simple fin form, one having an L-section outer region 9 for one-sixth of its length from the top with the remainder of simple fin form, and one having an L-section outer region 10 for one-ninth of its length from the bottom with the remainder of simple fin form. With such an arrangement, the horizontal force R at the top of the element was found to be approximately seven times greater than the horizontal force r at the bottom. Instead of L-sections on the splitter fins 4, T-sections could be used and the simple fin form parts could have a castellated profile (as shown by the broken lines 13). The fuel element is shown vertically orientated in a nuclear reactor core channel 11 defined by the wall 12.