Study of flow characteristics over wall-mounted trapezoidal structures at multiple inclinations

Abstract

This study numerically examines the flow field around two-dimensional wall-mounted trapezoidal obstacles under symmetric (both-side) and asymmetric (front-side and back-side) inclination at Re = 13,200, using the k–ω SST turbulence model. Validation of the model is conducted using experimental data for the velocity profile, and the results show good agreement. There is an observable impact of inclination on hydrodynamic properties, drag decreases from 1.033 to 0.610, and recirculation length decreases from Xr/h ≈ 15.21 to 9.30 for the case of both-side inclination. Maximum effects are observed in the front-side inclination, where drag is reduced from 1.018 to 0.457, and recirculation length from Xr/ℎ = 14.85 to Xr/h = 9.29, demonstrating that there is strong suppression of separation flow. On the other hand, back-side inclination provides a moderate level of drag reduction where Xr/h remains constant.