A Metho of Comparing Performance of Extended-Surface Heat Exchangers

摘要

The expression for the performance of a gas-cooled heat exchanger per unit of power expended to the flowing gas provides a useful figure of merit for extended-surface heat exchangers. As developed here, the expression accounts for the effects of both increased heat transfer coefficient and increased effective temperature difference with higher power expended. Previous expressions accounted for only the increase in heat transfer coefficient. The convenience of comparing different heat exchanger configurations, as well as different tube spacing in the same configuration, is shown.