Effect of Mesh Shape and Turbulence Model on Aerodynamic Performance at NACA ۴۴۱۵

This study uses three turbulence model variations, i.e., S - A, k - ε, and k – ω turbulence models. In addition, there are two variations of cell shape and three variations of cell number. The number of cells is ۵۰۰, ۵۰۰۰, ۵۰۰۰۰, and ۱۰۰۰۰۰. Verification is carried out in the mesh refinement study and validated by aerodynamic performances. Based on the mesh refinement study, quadrilateral cells with the k - ε are in the asymptotic convergence range. Based on the Cl, it can be concluded that the quadrilateral mesh with ۵۰۰۰۰ and ۱۰۰۰۰۰ cells simulated using the k-ε turbulence model shows very low errors, namely ۴.۱۱۵۱% and ۳.۸۶۴۳%, respectively. It shows consistency based on the quadrilaterals Cd mesh data with the k-ε and k-ω turbulence models. However, k-ε shows the lowest error with the number of cells ۵۰۰۰۰ and ۱۰۰۰۰۰, i.e., ۱۲۷.۷۶۸۲% and ۱۱۰.۴۱۷۵%, respectively. However, choosing mesh ۵۰۰۰۰ cells are advisable because it only takes ۲۳ minutes ۴۸ seconds in computation, while mesh ۱۰۰۰۰۰ cells take ۱ hour ۱۷ minutes ۲۱ seconds. Only Cm from quadrilateral mesh with the turbulence model k-ω shows consistency. An error of mesh ۵۰۰۰۰ cells is ۲۲.۰۷۱۷%, and the error value for ۱۰۰۰۰۰ cells is ۱۸.۱۶۳۰%. By considering computation time, mesh ۵۰۰۰۰ cells are preferable because it only takes ۲۷ minutes ۱۶ seconds, which is faster ۴۳ minutes ۱۴ seconds than ۱۰۰۰۰۰ cells.

Keywords:

Aerodynamic performances , Mesh refinement , Quadrilateral , Triangle , Turbulence models