Fuel Pin Bundle and Hexagonal Duct Mechanical Interaction

摘要

Cause and effect of the fuel pin bundle and the hexagonal duct mechanical interaction are discussed. An analytical method for calculating the bundle compressive stiffness and the pin-to-pin clearance is introduced. Analytical results for bundles of different sizes are compared to the available experimental values. It is concluded that (1) the bundle/duct interactive force and reduction in pin-to-pin clearance can vary over wide ranges due to tolerances on wire tension and wire pitch, (2) the maximum contact force and the maximum reduction in pin-to-pin clearance are more likely to occur near the edge pin than in the interior of a bundle, and (3) FFTF pin bundle will not experience adverse effects of bundle duct mechanical interaction. (ERA citation 04:008217)