Experimental Study of the Temperature Distribution Below Spacers in Smooth and Rough Rod Clusters.

摘要

An experimental investigation was performed of the heat transfer in smooth and rough rod bundles near spacer grids. Detailed wall temperature distributions were measured which clearly demonstrated that even in rod bundles roughened by artificial roughness there are no hot spots near spacer grids. On the basis of the few experimental results from the literature and the new data,heat transfer correlations are proposed for smooth and rough surfaces near spacer grids. These correlations allow a prediction to be made in a good approximation of the heat transfer near spacer grids as a function of the flow contraction due to the spacer.