Pressure Drop Model for CANDU Fuel Bundles in Crept Flow Channels

Abstract

Accurate predictions of the pressure drop in CANDU fuel channels are required for Channel Critical Power (CCP) evaluations. This paper describes the development and validation of a model to predict the multi-phase pressure drop across a string of CANDU fuel bundles in crept pressure tubes. It uses a novel approach comprised of two parallel flow paths to account for the effect of creep along with industry standard bundle form and friction loss coefficients. In principle it should predict the fuel string pressure drop for any envisioned fuel string axial heat flux distribution and pressure tube creep profile.