Fuel element for a boiling water reactor

摘要

Fuel element of a boiling water nuclear reactor, which fuel element, together with three further fuel elements, forms a quad group arranged around a central control rod, the quad group together with the control rod being designated a super cell. Each fuel element (16) contains a multiplicity of vertical fuel rods (12) with enriched nuclear fuel (24). The rods are arranged between a lower joining plate (13) and an upper joining plate (14) in a vertical fuel element box (1) which surrounds them together, the box being connected to a transition part (2) which is provided with holes (20) for an auxiliary flow outside the fuel element. The fuel element is characterised in that the auxiliary flow holes are arranged in such a manner that when the fuel element (16) together with the transition part (2) is rotated about the longitudinal axis of the fuel element through 90, 180 or 270 degrees, the auxiliary flow emerging from the said holes is directed away from the control rod. This can be achieved with the aid of a rotatable ring provided with holes.