Numerical investigation of flow around cylinder at Reynolds number=3900 with large eddy simulation technique: Effect of spanwise length and mesh resolution

Flow around a cylinder at a Reynolds number of 3900 was studied using large eddy simulation with ICEM CFD and Fluent tools for meshing and analysis, respectively. Although this issue has been explored by numerous researchers, a discrepancy still exists in the results, particularly in calculating the angle of separation, recirculation length, and statistics in the wake region behind the cylinder. In addition, the effect of spanwise grid and near-field grid resolution on the wake region needs to be addressed. This study reviews previous work and performs analyses according to the literature recommendations. The effect of spanwise length (4D, 8D, and 16D), mesh resolution in the spanwise direction (1, 10, 20, 40, 60, 80, and 160 elements), and near-field grid on calculating recirculation length, angle of separation, and wake characteristics is investigated. Hydrodynamic values and pressure distribution around the cylinder are analyzed. The wake behind the cylinder is investigated within 10 diameters. This study concluded that compared with spanwise length, mesh resolution in the spanwise direction and near-field grid are more important factors for good-quality results.