Print Email Facebook Twitter Rheology-based wall function approach for wall-bounded turbulent flows of Herschel–Bulkley fluids Title Rheology-based wall function approach for wall-bounded turbulent flows of Herschel–Bulkley fluids Author Yusufi, B.K. (TU Delft Sanitary Engineering) Kapelan, Z. (TU Delft Sanitary Engineering) Mehta, D. (TU Delft Sanitary Engineering) Date 2024 Abstract Modeling fully developed turbulent flow for Herschel–Bulkley (HB) fluids in pipes is a long-standing challenge. Existing semi-empirical, theoretical, and numerical methods are either inconsistent with experimental data or are validated for low Reynolds numbers. This study focuses on validating a novel approach using rheology-based wall functions within Reynolds-averaged Navier–Stokes solvers. Simulations of wall shear stress and velocity profiles were conducted across a wide range of Reynolds numbers using a single-phase HB fluid, with measurements taken both upstream and downstream of a 90 pipe bend. Two turbulence closure models, the k–e model and the Reynolds stress model, were employed with the wall function implemented as a specified shear boundary condition. Results demonstrate significant improvements over the Newtonian-based models, such as standard wall function by Launder–Spalding or with available semi-empirical models, achieving strong statistical correlations and minimal deviation (from the experimental findings) at high Reynolds numbers. The study also examines the utility of the wall viscosity Reynolds number and assesses the reliability of semi-empirical models for HB fluids. These findings offer valuable insights for enhancing modeling accuracy in complex fluid flow scenarios, with potential applications spanning industries like mining, chemical processing, petroleum transportation, and sanitation systems, providing practical alternatives to costly experimental procedures in pipe systems. To reference this document use: http://resolver.tudelft.nl/uuid:10f466d7-2b4a-45a5-984f-366f41028a15 DOI https://doi.org/10.1063/5.0180663 ISSN 1070-6631 Source Physics of Fluids, 36 (2) Part of collection Institutional Repository Document type journal article Rights © 2024 B.K. Yusufi, Z. Kapelan, D. Mehta Files PDF 023112_1_5.0180663.pdf 2.95 MB Close viewer /islandora/object/uuid:10f466d7-2b4a-45a5-984f-366f41028a15/datastream/OBJ/view