Hydrodynamics and heat transfer in single-phase fluid flows in artificially rough pipes

Studies on hydraulic resistance and heat transfer in pipes with artificial roughness of different profiles are reviewed; artificially rough surfaces, flow regimes, boundaries of flow regimes, and equations for calculation of the coefficients of hydraulic resistance and heat transfer during single-phase flow in rough pipes are classified. it has been ascertained that many available equations for calculation of hydraulic resistance and heat transfer for single-phase flows in artificially rough channels, however, do not allow these data to be always used, because of the many types and forms of artificial roughness. the generalized equations presented in this review mainly relate to flows in channels with sand-grain roughness. the absence of studies of the hydraulic resistance and heat transfer in single-phase flows in rough channels with flow swirling is noted, which is an effective way for intensification of heat transfer in practical applications.