SYSTEMS AND METHODS FOR INCREASED STABILITY NUCLEAR FUEL CASTINGS

摘要

Nuclear fuel assembly support castings direct fluid flow through nuclear fuel assemblies with relatively lower decay ratios and thus improved flow stability. The castings include an internal flow passage that is elongated to increase fluid flow inertia. The passage may be in excess of 0.3 meters and up to several meters in a straight, vertical direction that does not disrupt inertial fluid flow. Castings may omit an entry orifice and replicate any orifice-driven pressure drop with a specifically-sized flow passage that causes a similar pressure drop, or castings may use a side or bottom entry orifice at an entrance to the passage. Castings accommodate any number of fuel assemblies and other core structures including control blades, instrumentation tubes, core plates, and other core structures, such as four fuel assemblies arranged in a grid on the casting with a cruciform control element extending through a center of the casting.

主权项

1. A nuclear fuel support casting comprising:
a fluid outlet shaped to receive an end of a nuclear fuel assembly; a fluid inlet vertically below the fluid outlet; and an internal flow path directly between the fluid inlet and the fluid outlet, wherein the internal flow path is approximately 0.8 or more meters long.