Annual meeting of the American Nuclear Society

Abstract

The aim of this paper is to present research results on thermal mixing between subchannels of a simulated nuclear fuel rod bundle. Experiments were carried out with singhe phase freon-12 flowing in-line through a cluster of nine electrically heated steel tubes assembled on a square array. This test section was vertically mounted and the coolant flowed upwards. System thermodynamic parameters were controlled and recorded. Dry wall and fluid local temperatures, in strategic positions at the top end of the heated length, were particularly measured. Fluid flow and heat trabsfer conditions for axial turbulent flow were analytically studied. Calculated velocity and temperature fields were used to compute corner, side and central subchannel coolant mass flow rates and enthalpies.