Performance of Perforated Heat Exchanger Surfaces

Abstract

Heat transfer and flow friction behavior have been measured for plain and perforated plate-fin and 10-deg herringbone surfaces. For the range of geometries and Reynolds numbers studied, the perforations produced no significant improvement in heat transfer for the same pressure drop. Heat transfer behavior was determined with the “single blow” transient technique. The “initial rise” evaluation procedure was used for low Ntu test packs. Entrance length effects on both heat transfer and friction behavior were correlated for L/4rh as low as 45.