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A single comprehensive equation is developed for the rate of heat and mass transfer from a circular cylinder in crossflow, covering a complete range of Pr (or Sc) and the entire range of Re for which data are available. This expression is a lower bound (except possibly for RePr < 0.2); free-stream turbulence, end effects, channel blockage, free convection, etc., may increase the rate. In the complete absence of free convection, the theoretical expression of Nakai and Okazaki may be more accurate for RePr < 0.2. The correlating equation is based on theoretical results for the effect of Pr in the laminar boundary layer, and on both theoretical and experimental results for the effect of Re. The process of correlation reveals the need for theoretical results for the effect of Pr in the region of the wake. Additional experimental data for the effect of Pr at small Pe and for the effect of Re during the transition in the point of separation are also needed.

A single correlating equation is constructed for the mean Nusselt (or Sherwood) number for all Reynolds and Prandtl (or Schmidt) numbers, and for either uniform wall temperature or a uniform heat flux density. The applicability of this equation is limited to fully developed flow in smooth tubes. However, developing as well as fully developed convection is considered. A corresponding equation is constructed for the friction factor for all Reynolds numbers. These expressions are based on interpolation between the various limiting cases, using the model of Churchill and Usagi. The correlating equations appear to represent available experimental and theoretical values within their uncertainty and to be at least as accurate as prior expressions for restricted ranges of Re and Pr or Sc. The equations are suitable for hand-held computers as well as for incorporation in algorithms for design and optimization.

Asymptotic solutions for Pr → 0 and Pr → ∞ and numerical solutions for intermediate Pr were obtained for a uniformly heated flat plate. The method of Churchill and Usagi was utilized to construct a simple correlation for these values. The same method was used to develop simple correlations for plug flow and fully developed flow in a uniformly heated tube. These correlations were in turn combined to develop correlations for the available experimental data and computed values for developing flow in a uniformly heated tube. Derivations and test calculations in which convection normal to the wall was neglected reveal that this error is significant but insufficient to explain all of the discrepancies in the computed values.