{"id":289021,"date":"2023-06-15T23:51:08","date_gmt":"2023-06-15T23:51:08","guid":{"rendered":"\/forum\/forums\/topic\/incorrect-coefficient-of-lift-for-a-cube-at-45-deg-aoa\/"},"modified":"2023-06-15T23:51:08","modified_gmt":"2023-06-15T23:51:08","slug":"incorrect-coefficient-of-lift-for-a-cube-at-45-deg-aoa","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/incorrect-coefficient-of-lift-for-a-cube-at-45-deg-aoa\/","title":{"rendered":"Incorrect Coefficient of Lift for a Cube at 45 Deg AoA"},"content":{"rendered":"

I’m currently performing a grid independence study on a cube at different orientations. The cube gave correct results for 0 Deg AoA as its CL was basically 0 and the CD was 1.046. However, when I rotated the overset mesh 45 degrees and appended the bulk region and calculated, the results are incorrect. The CD is correct at 0.84, but the CL is 0.1222 which is incorrect as it should be zero. I have tried increasing the mesh count by 2x and that gave the same results. I have also lowered y+ to 0.2 from 10, treated the edges of the cube with extra cells, tried a approach without the rotate feature, made one without overset, and I’ve even been stricter on mesh orthogonality, aspect ratio, and skewness. All of these have produced the same steady results. I’ve also tried the laminar solver, SA, and k-omega SST. I have done transient cases as well and they converge to these results after a few timesteps. I even ran the case for 10 seconds out and it stayed converged to this solution. All I know is that this is a symmetric body and should have a CL of 0. Any help would be appreciated.<\/p>\n","protected":false},"template":"","class_list":["post-289021","topic","type-topic","status-closed","hentry","topic-tag-3d","topic-tag-ansys-cfd-1","topic-tag-fluent","topic-tag-lift-coefficient"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t