ISSN Online: 2377-424X
ISBN Print: 0-89116-909-1
International Heat Transfer Conference 9
HEAT TRANSFER DATA FOR NATURAL CONVECTION CONDITIONS IN REACTOR CALCULATIONS
Résumé
Measurements of heat transfer coefficient have been made in natural circulation of nitrogen through an annulus formed from a rough surface model fuel pin and a smooth channel. The annulus formed part of a closed pressurised loop. Results are correlated by Nu = 0.068 (GrPr)0.37 in the range 106 < GrPr < 109. Equivalent measurements for a cluster of pins simulating a CAGR fuel element gave agreement within 10%. The correlation is compared with some data in the literature. When compared with buoyancy-free forced convection data obtained in the same annulus it gives Nusselt numbers up to × 2 higher. Its use is recommended for calculations in reactor passages, subject to satisfying a buoyancy-domination criterion of Gr/Re13 > 10−4.