aerodynamic and static aeroelastic numerical simulations for the 6th - PowerPoint PPT Presentation

aerodynamic and static aeroelastic numerical simulations for the 6th aiaa cfd drag prediction workshop 6th AIAA CFD Drag Prediction Workshop - 2016 Rodrigo Felix de Souza Murilo C. Mestriner Maximiliano A. F. de Souza Marcello Areal Ferrari Carlos Breviglieri Cleber Spode June 16, 2016 Embraer S/A

Outline Introduction Numerical simulations results Case 1 Case 2 Case 3 Case 5 Bonus track 1

introduction

Considered Cases and solver setup SST and SA (case 1 only) Minmod compression 2 : TVD limiter Nodal-based : Polynomial type Finite volume, 2nd order : Spatial discretization Point-implicit (SGS) / Algebraic multigrid : Time integration : Considered four series of computations: Turbulence model Pre-conditioned compressible RANS, perfect gas : Formulation CFD++ (14.1.1) : Solver Solver setup ∙ Case 5: CRM WB Coupled Aero-Structural Simulation; ∙ Case 3: CRM WB Static Aero-Elastic Effect; ∙ Case 2: CRM Nacelle-Pylon Drag Increment; ∙ Case 1: Verification study; 3

Grids Grids @ Tiny level (a) CommonHybrid (b) CustomHexa 4

Grids Grids @ Tiny level (c) CustomHybrid-I (d) CustomHybrid-A 5

Grids 70.3 We matched the gridding guidelines for number of cells! 68.6 25.7 20.3 8.0 CustomHybrid-I 72.6 23.9 19.7 9.4 CustomHybrid-A 69.6 20.0 Grid sizes in million (WB-AE275): 20.3 CustomHexa 271.2 66.2 83.6 20.5 CommonHybrid Cells Nodes Cells Nodes Fine Tiny 6

numerical simulations results

Case 1: Verification Study = SA and SST (CFD++) Turbulence model: TMBWG Family II NACA 0012 Grid: 10 degrees AOA Flow condition: 6 million = Re 0.15 = M 8

Case 1: Verification Study Grid convergence: Lift 9 1.110 CFD++ - SST CFD++ - SA CFL3D - SA FUN3D - SA 1.100 1.090 C L 1.080 1.070 1.060 0.000 0.002 0.004 0.006 0.008 0.010 h=sqrt(1/N)

Case 1: Verification Study Grid convergence: Drag 9 0.018 CFD++ - SST CFD++ - SA CFL3D - SA 0.017 FUN3D - SA 0.016 C D 0.015 0.014 0.013 0.012 0.000 0.002 0.004 0.006 0.008 0.010 h=sqrt(1/N)

Case 1: Verification Study Grid convergence: Drag (pressure component) 9 0.0120 CFD++ - SST CFD++ - SA 0.0110 CFL3D - SA FUN3D - SA 0.0100 0.0090 C D P 0.0080 0.0070 0.0060 0.0050 0.0040 0.000 0.002 0.004 0.006 0.008 0.010 h=sqrt(1/N)

Case 1: Verification Study Grid convergence: Drag (viscous component) 9 0.0062 CFD++ - SST 0.0062 CFD++ - SA CFL3D - SA 0.0061 FUN3D - SA 0.0061 0.0060 0.0060 C D V 0.0059 0.0059 0.0058 0.0058 0.0057 0.0057 0.000 0.002 0.004 0.006 0.008 0.010 h=sqrt(1/N)

Case 1: Verification Study Pressure distribution @ finest grid 10 -7.0 CFD++ - SST CFD++ - SA -6.0 CFL3D - SA FUN3D - SA -5.0 -4.0 -3.0 C P -2.0 -1.0 0.0 1.0 2.0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 x/c

Case 1: Verification Study Pressure distribution @ finest grid 10 -7.0 CFD++ - SST -6.0 CFD++ - SA -6.0 CFL3D - SA -5.5 FUN3D - SA -5.0 -5.0 -4.0 -4.5 Cp @ L.E. -3.0 -4.0 C P 0.00 0.01 -2.0 -1.0 0.0 1.0 2.0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 x/c

Case 1: Verification Study Skin friction @ finest grid 11 0.035 CFD++ - SST CFD++ - SA 0.030 CFL3D - SA FUN3D - SA 0.025 0.020 0.015 C F X 0.010 0.005 0.000 -0.005 -0.010 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 x/c

Case 2: CRM Nacelle-Pylon Drag Increment : Aeroelastic deflection at the angle-of-attack 2.75 degrees Geometry: T,C,M,F : CustomHybrid-A T,C,M,F : CustomHybrid-I T,C,M,F,X,U (WB only) : CustomHexa T,C,M,F CommonHybrid Flow condition: Grids: SST (CFD++) Turbulence model: 0.50 = CL 5 million = Re 0.85 = M 12

Case 2: CRM Nacelle-Pylon Drag Increment Total drag convergence @ WB 13 0.0260 CommonHybrid WB ⎯ CustomHexa 0.0259 ↕ CustomHybrid-A CustomHybrid- I 1 Drag Count ⎯ 0.0258 ➪ 0.0257 CustomHybrid-I ➪ CustomHexa ➪ CustomHybrid-A 0.0256 CD TOT 0.0255 ➪ CommonHybrid 0.0254 0.0253 0.0252 100M 26M 20M 8M 0.0251 0.0250 0.0e+00 5.0e-06 1.0e-05 1.5e-05 2.0e-05 2.5e-05 3.0e-05 GRIDFAC = 1/GRIDSIZE (2/3)

Case 2: CRM Nacelle-Pylon Drag Increment Total drag convergence @ WBNP 13 0.0284 CommonHybrid WBNP ⎯ CustomHybrid-A 0.0283 ↕ CustomHybrid- I 1 Drag Count ⎯ 0.0282 ➪ CustomHybrid-I 0.0281 0.0280 CD TOT 0.0279 ➪ CustomHybrid-A 0.0278 0.0277 0.0276 ➪ CommonHybrid 91M 36M 28M 11M 0.0275 0.0274 0.0e+00 5.0e-06 1.0e-05 1.5e-05 2.0e-05 2.5e-05 3.0e-05 GRIDFAC = 1/GRIDSIZE (2/3)

Case 2: CRM Nacelle-Pylon Drag Increment Delta NP drag convergence (WBNP-WB) 13 0.0028 CommonHybrid ∆ NP ⎯ CustomHybrid-A 0.0027 ↕ CustomHybrid- I 1 Drag Count ⎯ 0.0026 TINY 0.0025 FINE ➪ CustomHybrid-I 0.0024 ∆ CD TOT TINY 0.0023 ➪ CustomHybrid-A FINE 0.0022 ➪ CommonHybrid FINE 0.0021 TINY 0.0020 0.0019 0.0018 0.0e+00 5.0e-06 1.0e-05 1.5e-05 2.0e-05 2.5e-05 3.0e-05 GRIDFAC = 1/GRIDSIZE (2/3)

Case 2: CRM Nacelle-Pylon Drag Increment Angle of attack for each grid @ CL 0.50 13 3.00 CommonHybrid ALPHA CustomHexa ⎯ WB 2.90 ↕ CustomHybrid-A CustomHybrid- I 0.1 ° ⎯ 2.80 2.70 ➪ CommonHybrid 2.60 ALPHA [ ° ] ➪ CustomHexa 2.50 ➪ CustomHybrid-A 2.40 ➪ CustomHybrid-I 2.30 2.20 100M 26M 20M 8M 2.10 2.00 0.0e+00 5.0e-06 1.0e-05 1.5e-05 2.0e-05 2.5e-05 3.0e-05 GRIDFAC = 1/GRIDSIZE (2/3)

Case 2: CRM Nacelle-Pylon Drag Increment Pressure distribution @ wing section 11 (Fine grid) 13 -1.40 CommonHybrid -1.20 CustomHexa CustomHybrid-A -1.00 CustomHybrid-I -0.80 -0.60 -0.40 C p -0.20 0.00 0.20 0.40 0.60 0.80 1.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 x/c

Case 2: CRM Nacelle-Pylon Drag Increment : : Cells : Nodes CustomHybrid-I-A (F) : Cells Side-of-body separation (SOB): 14 Nodes CustomHexa (T) : Cells : Nodes CommonHybrid (T) ≈ 20 mi ≈ 20 mi ≈ 24 mi ≈ 84 mi ≈ 20 mi ≈ 73 mi

Case 3: CRM WB Static Aero-Elastic Effect Grids: SST (CFD++) Turbulence model: @ Medium level (17M nodes) CustomHybrid-I @ Medium level (17M nodes) CustomHybrid-A @ Medium level (45M nodes) CustomHexa @ Medium level (45M nodes) CommonHybrid 2.50 | 2.75 | 3.00 | 3.25 | 3.50 | 3.75 | 4.00 degrees Flow condition: = AE 2.50 | 2.75 | 3.00 | 3.25 | 3.50 | 3.75 | 4.00 degrees = AOA 5 million = Re 0.85 = M 15

Case 3: CRM WB Static Aero-Elastic Effect Wing deformation effect on lift and drag polar Decreased lift slope Decreased tip incidence Increased AE (b) Drag Polar (a) Lift 16 CustomHexa 0.64 0.0410 0.60 0.0370 C L 0.56 C D AE2.50 0.0330 AE2.50 AE2.75 AE2.75 0.52 AE3.00 AE3.00 AE3.25 AE3.25 AE3.50 AE3.50 AE3.75 AE3.75 AE4.00 AE4.00 0.48 0.0290 2.50 2.75 3.00 3.25 3.50 3.75 4.00 0.56 0.60 0.64 AOA [deg] C L

Case 3: CRM WB Static Aero-Elastic Effect Wing deformation effect on lift and drag polar (b) Drag Polar (a) Lift 16 CustomHexa 0.64 0.0410 0.60 0.0370 C L 0.56 C D 0.0330 0.52 AE2.50 AE2.50 AE4.00 AE4.00 AEswp AEswp 0.48 0.0290 2.50 2.75 3.00 3.25 3.50 3.75 4.00 0.56 0.60 0.64 AOA [deg] C L Increased AE → Decreased tip incidence → Decreased lift slope

Case 3: CRM WB Static Aero-Elastic Effect (a) Lift (b) Drag Mesh effect on lift and drag 17 0.660 0.0440 CommonHybrid CommonHybrid CustomHexa CustomHexa CustomHybrid-A CustomHybrid-A CustomHybrid-I CustomHybrid-I 0.0400 0.600 0.0360 C D C L 0.0320 0.540 0.0280 0.480 0.0240 2.50 2.75 3.00 3.25 3.50 3.75 4.00 2.50 2.75 3.00 3.25 3.50 3.75 4.00 AE [deg] AE [deg]

Case 3: CRM WB Static Aero-Elastic Effect Mesh and wing deformation effect on Cp distribution (b) Wing Section 11 - AE4.00 - AOA=4.0 o (a) Wing Section 11 - AE2.50 - AOA=2.5 o 18 -1.40 -1.40 CommonHybrid CommonHybrid -1.20 CustomHexa -1.20 CustomHexa CustomHybrid-A CustomHybrid-A -1.00 -1.00 CustomHybrid-I CustomHybrid-I -0.80 -0.80 -0.60 -0.60 -0.40 -0.40 C p -0.20 C p -0.20 0.00 0.00 0.20 0.20 0.40 0.40 0.60 0.60 0.80 0.80 1.00 1.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 x/c x/c

Conclusion - Case 1 ∙ Results for CFD++ SA are similar to CFL3D and FUN3D except for a shift in total drag; ∙ The difference comes mainly from the pressure drag component; ∙ The SST turbulence model generates different results in comparison to SA; 19

Conclusion - Case 2 and 3 ∙ Despite the difference in grid cells: ∙ The CustomHybrid-A is only 1 to 2 dc away from CommonHybrib (WB and WBNP); ∙ On the other hand, CustomHybrid-I generates differences in drag up to 5 dc for the same number of elements; ∙ This result highlights the importance of the way the elements are distributed; ∙ The SOB separation seems to be more related to gridding strategy than to the grid size; ∙ The grid has a significant influence on predicting CD, CL and CP for higher AE deflections; 20