Pressure drop of turbulent flow across 90 round bends with 10mm inside diameter investigated by employing the shear stress transport turbulent model for numerous curvature ratios and flow conditions. A total of 10 flow velocities varied from 1 to 10 m/s and 17 curvature radii between 5 and 300 mm were examined. Velocity profiles were evaluated at eight locations to examine the entrance effect. The simulation results were verified by comparing the evaluated Darcy friction factor with a well-known published correlation. The obtained results of bend pressure drop demonstrate the domination of the curvature ratio effect on the pressure drop over the influence of other factors. The computed pressure loss across the bend in terms of pressure loss coefficient and equivalent length to diameter ratio shows a good agreement with various published data in the literature with maximum average error. The coincidence between the results and the published data verifies the accuracy of the employed model to evaluate the pressure drop of turbulent flow throughout 90 bends for the applied boundary conditions.
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