TAS Code, FaSTAR, and Cflow Results for the Sixth Drag Prediction Workshop

Three mixed-element unstructured Reynolds-averaged Navier-Stokes solvers, the TAS code, FaSTAR, and Cflow, were applied to the Sixth AIAA Drag Prediction Workshop test cases to investigate the accuracy of the solvers with committee-provided grids and custom participant-generated grids by MEGG3D, BOXFUN, and the Cflow built-in grid generator. Solutions were obtained for the verification study using the two-dimensional NACA 0012 airfoil (test case 1), the NASA common research model nacelle-pylon drag incremental study (test case 2), and the common research model wing/body static aeroelastic effect study (test case 3). In test case 1, the three solvers used the same turbulence model, the Spalart-Allmaras one-equation turbulence model without the trip term for transition and without the ft2 function, and their grid convergence trends for lift, drag, and pitching moment coefficients were similar to that of FUN3D, CFL3D, and TAU. In test case 2, the TAS code with the NASA GeoLab grids and with MEGG3D grids, FaSTAR with the NASA GeoLab grids, and Cflow with its own grids predicted nacelle-pylon drag increment well. In test case 3, the three solvers predicted force and moment fairly comparable with experiment if support system interference effects were considered.