Accepted for Publication December 9, 1994Quantitative correlation factors and functions are derived that relate the inside peak heat fluxes for cases involving single-side sine and uniform external heat flux distributions, which are applied to a circular coolant channel. The results are also presented in terms of a map that gives insight on how to improve high-heat-flux accommodation. The results show that similarities and differences depend on two dimensionless parameters: the Biot number Bi and the channel radius ratio Ro = ro/ri.