Interaction Effects Between Laminar Natural Convection and Surface Thermal Radiation in PHWR Reactor Channels

Abstract

Pressurized Heavy Water Reactor (PHWR) reactor channel consists of a pressure tube (PT), which is concentrically placed inside the calendria tube (CT). After a hypothetical loss of coolant accident, sagging or ballooning of the PT may occur and physical contact between PT and CT takes place. Under this condition, knowledge of temperature distributions in PT and CT are essential to assess their structural integrity. Towards this, a 2-D CFD study has been carried out to understand the natural convection of CO₂ and surface thermal radiation. Detailed parametric study has been carried for various values of temperature difference, emissivity and eccentricity.