Selection and justification of riblet geometry for hydraulic loss reduction and heat transfer enhancement in tubular components

This article addresses the critical problem of reducing hydraulic losses and enhancing heat transfer in tubular components. To achieve this, a comparative analysis of triangular, trapezoidal, and rectangular riblet profiles was conducted using numerical simulation of turbulent flow (k–? SST model) in ANSYS Workbench. It was found that, given identical base dimensions, rectangular riblets exhibit the best performance. They provide the minimum pressure drop (1227.38 Pa compared to 1533.25 Pa for triangular profiles) and maximum heat transfer (Nusselt number Nu = 116.7). It is demonstrated that the rectangular geometry more effectively displaces large vortices away from the boundary layer, which not only reduces frictional resistance but also minimizes the likelihood of sediment deposition on the pipe walls.
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