The structure of heat transfer equations for bundles of staggered tubes with external annular fins, operating in cross flow

It is shown on the basis of a study of heat transfer coefficients in thirty-two bundles of staggered tubes with external annular fins, operating in cross flow, that the exponent m in the expression Nu/sub ann/ = CR/sub e//sup m/ depends significantly on the relative tube spacing and the fin geometry. The studies were performed by complete thermal simulation at Re/sub d/ between 2 x 103 and 6 x 104