Accession Number : AD0717661
Title : The Influence of Brazing on Very Compact Heat Exchanger Surfaces
Descriptive Note : Technical rept.
Corporate Author : STANFORD UNIV CA DEPT OF MECHANICAL ENGINEERING
Personal Author(s) : Shah, Ramesh K ; London, A L
PDF Url : AD0717661
Report Date : Nov 1970
Pagination or Media Count : 64
Abstract : Three geometrically similar offset rectangular plate-fin surfaces with area densities in the range from 900 to 2000 sq ft/cu ft were tested to establish the heat transfer, j-NR, and flow friction, f-N sub R, characteristics. The Reynolds number range was from 60 to 3000. One surface was unbrazed while the other two, because of a two-to-one difference in plate, fin and offset spacing dimensions, were characterized by different degrees of brazing 'roughness'. The test results reveal a relatively small effect of brazing on j-N sub R, but a significant influence on f-N sub R, with a 35 to 50 percent higher friction for the brazed surface. There is an 'area penalty' of 14 percent due to brazing associated with the complete coverage of the interface area at the brazed joints. The magnitude of this penalty depends on the geometry of the surface.
Descriptors : *HEAT EXCHANGERS, BRAZING, HEAT TRANSFER, SURFACE PROPERTIES
Subject Categories : Air Condition, Heating, Lighting & Ventilating
Distribution Statement : APPROVED FOR PUBLIC RELEASE