Fully developed viscous—flow heat transfer in curved circular tubes with uniform wall temperature

Abstract

Abstract Fully developed forced‐convective heat transfer to viscous flow of a constant‐property Newtonian fluid in curved circular tubes was studied theoretically for a uniform‐wall‐temperature boundary condition. Numerical solutions were obtained over a wide range of Prandtl numbers for Dean numbers as large as 1,200. The curvature ratio (radius of bend/inside radius of tube) was included as an independent parameter and, for values as small as 10, was found to have a negligible effect on the peripherally averaged Nusselt number. The average Nusselt numbers for the important Prandtl number range of 0.7 to 5 were correlated by N Nu = 0.836 N De 0.5 N Pr 0.1 for N De ≥ 80.