AIAA CFD 5^th Drag Prediction Workshop

June 2012, New Orleans, LA

10 December 2011

Note: The Configuration Geometry, Test Cases, and Gridding Guidelines are current as of 10 December 2011, but are subject to changes as developments require. Please check the website periodically for updates http://aaac.larc.nasa.gov/tsab/cfdlarc/aiaa-dpw/, and/or register with aiaadpw@gmail.com to be notified directly.

Test Cases:

Case 1 – NASA Common Research Model (CRM) Wing-Body Common Grid Study:

1. Grid Convergence study at Mach = 0.85, C_L = 0.500 (±0.001)

- Grid refinement series from the Common Grid Sequence consisting of at least four grid levels (Coarse, Medium, Fine, Extra-Fine Grids). Target grids should range from 3 to 50 million unknowns.

- Chord Reynolds Number Rn = 5x10⁶ based on c_REF = 275.80 in

- Reference Temperature = 100°F

- Moment reference center is x_REF = 1325.90 in, z_REF = 177.95 in

2. Optional Grid Convergence study using participant developed grids:

- All participants are encouraged to build their own grids using ‘best practice’ techniques. IGES and CATIA models of the 1-g shape at the design point are available for grid construction. A family of grid sizes should be developed in the range described above suitable for Grid Convergence Study. All grids used for results presented at the workshop must be submitted to the DPW Organizing Committee to be made available to all interested parties. Results and grids will be published electronically on the DPW website.

Case 2 – NASA Common Research Model (CRM) Wing-Body Buffet Study:

- Mach = 0.85

- Drag Polar for alpha = 2.50°, 2.75°, 3.00°, 3.25°, 3.50°, 3.75°, 4.00°

- Medium Grid used in Case 1 from the Common Grid Sequence or participant developed grids

- Chord Reynolds Number Rn = 5x10⁶ based on c_REF = 275.80 in

- Reference Temperature = 100°F

Case 3 (Optional) – Turbulence Model Verification:

Details for the following three cases are listed on the TMBWG website: http://turbmodels.larc.nasa.gov/

For each case use the three finest supplied grids.

1. 2D Zero Pressure Gradient Flat Plate: M = 0.20; Re_L = 5 x10⁶; T_ref = 540 R

2. 2D Bump-in-channel: M = 0.20; Re_L = 3 x 10⁶; T_ref = 540 R

3. 2D NACA 0012 Airfoil: M = 0.15; Re_C = 6 x 10⁶; T_ref = 540 R

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Notes:

· Common Research Model Reference Geometry:

o S_REF= 594,720 in² (4130 ft²)

o c_REF= 275.80 in

o x_REF= 1325.90 in

o z_REF= 177.95

o AR= 9.0

· Geometry Reference:

o JC Vassberg, MA DeHaan, SM Rivers, and RA Wahls, “Development of a Common Research Model for Applied CFD Validation Studies,” AIAA Paper 2008-6919, AIAA Applied Aerodynamics Conference, Honolulu, HI, August, 2008.

· Simulations are to be “free air”; no wind tunnel walls or model support systems are to be included.

· Boundary layer is to be fully turbulent for Case 1 and Case 2.