Document
AIAA SciTech 2016, Jan 4-8 2016, San Diego, CA www.nasa.gov Michael J. Schuh and Joseph A. Garcia NASA Ames Research Center Melissa B. Carter and Karen A. Deere NASA Langley Research Center Daniel M. Tompkins Boeing Research & Technology Paul M. Stremel Science and Technology Corporation NASA Environmentally Responsible Aviation Hybrid Wing Body Flow-Through Nacelle Wind Tunnel CFD Motivation Geometry Overview of simulations Four CFD codes Simulation results for five different configurations Summary & Conclusions
Outline • • • • • •
Support pretest configuration changes and wind tunnel model design Quantify installation effects Guide post test data corrections Extrapolate from wind tunnel to free flight Increased confidence in CFD predictions – especially before the availability of wind tunnel data Different people running different CFD codes often results in better and higher confidence results Opportunity for CFD modelers to learn from each other
Motivation Why were we running CFD? • • • • Why multiple codes? • • •
17 in 83 in 158 in
5.75% of Full Scale
HWB Test Model – Cruise Configuration
Wing MLL L23 L13 L33 L22 Gap L32 L12 Overhang (-) as shown L21 Landing Krueger grid L11 L31 positions are a 3x3 matrix Angle
Baseline and Acoustic Krueger
Wing MLL L23 L13 L33 L22 Gap L32 L12 Overhang (-) as shown L21 Landing Krueger grid L11 L31 positions are a 3x3 matrix Angle
Baseline and Acoustic Krueger
Top View of Krueger Brackets
Model has 5 wind tunnel Krueger brackets. Flight vehicle would have smaller and 20+ Krueger brackets.
Center Bracket
Bottom View of Krueger Brackets
All results are for Freestream Mach = 0.2
Free Air Free Air 14’x22’ Wind Tunnel Free Air 40’x80’ Wind Tunnel
Cruise • Baseline Krueger no brackets • • Acoustic Krueger w/brackets • •
CFD Configurations
Used by NASA LaRC, NASA LaRC developed Tetrahedral cell meshes Used by Boeing, COTS code Triangular prisms, tetrahedrals, and pyramids meshes Used by NASA ARC, COTS code Polyhedral volume mesh with prism layer on surface Used by NASA ARC, NASA LaRC developed with ARC origin Overset structured meshes – – – – – – – – USM3D CFD++ STAR-CCM+ OVERFLOW All Codes ran with y+ < 1. All but STAR-CCM+ used SA turbulence model, STAR-CCM+ was run with SST turbulence model.
CFD Codes • • • • •
Free Air Free Air 14’x22’ Wind Tunnel Free Air 40’x80’ Wind Tunnel
Cruise • Baseline Krueger no brackets • • Acoustic Krueger w/brackets • •
CFD Configurations
Angle of Attack
Corrected Tunnels
14x22, Cruise, r84 40x80, Cruise, r60 and q.
40x80, Cruise, R96 Wind tunnel data classically corrected for
Cruise Lift
Lift Coefficient
Cruise with 14x22 Sting
Angle of Attack
Corrected Tunnels
Cruise with 40x80 Sting
14x22, Cruise, r84 40x80, Cruise, r60 and q.
40x80, Cruise, R96 Wind tunnel data classically corrected for
Cruise Lift
Lift Coefficient
Cruise with 14x22 Sting
Angle of Attack
Free Air CFD Corrected Tunnels
Cruise with 40x80 Sting
14x22, Cruise, r84 40x80, Cruise, r60 and q.
40x80, Cruise, R96 40x80 Sting, CFD++, Cruise 14x22 Sting, USM3D, Cruise 14x22 Sting, OVERFLOW, Cruise 40x80 Sting, STAR-CCM+, Cruise Wind tunnel data classically corrected for Good comparison up to stall
Cruise Lift
Lift Coefficient
Free Air CFD Corrected Tunnels
Angle of Attack
Cruise with 14x22 Sting
Cruise with 40x80 Sting
14x22, Cruise, r84 40x80, Cruise, r60 40x80, Cruise, R96 40x80 Sting, CFD++, Cruise 14x22 Sting, USM3D, Cruise 14x22 Sting, OVERFLOW, Cruise 40x80 Sting, STAR-CCM+, Cruise Good comparison up to stall
Cruise Drag
Drag Coefficient Angle of Attack
Cruise with 14x22 Sting
Cruise with 40x80 Sting
14x22, Cruise, r84 40x80, Cruise, r60 40x80, Cruise, R96 40x80 Sting, CFD++, Cruise 14x22 Sting, USM3D, Cruise
Free Air CFD Corrected Tunnels
14x22 Sting, OVERFLOW, Cruise 40x80 Sting, STAR-CCM+, Cruise Scatter due to expanded scale Good comparison up to stall
Cruise Pitching Moment
Pitching Moment Coefficient
Free Air Free Air 14’x22’ Wind Tunnel Free Air 40’x80’ Wind Tunnel
Cruise • Baseline Krueger no brackets • • Acoustic Krueger w/brackets • •
CFD Configurations
Baseline Krueger with 14x22 Sting
Angle of Attack No Krueger brackets modeled in CFD 14x22, Baseline 45-2x2, r96 14x22 Sting, USM3D, Baseline 45-2x2
Free Air CFD Corrected Tunnels
14x22 Sting, OVERFLOW, Baseline 45-2x2 14x22 Sting, STAR-CCM+, Baseline 45-2x2
Baseline Krueger Lift
Lift Coefficient No Krueger brackets modeled in CFD
Baseline Krueger with 14x22 Sting
Angle of Attack 14x22, Baseline 45-2x2, r96
Free Air CFD Corrected Tunnels
14x22 Sting, USM3D, Baseline 45-2x2 14x22 Sting, OVERFLOW, Baseline 45-2x2 14x22 Sting, STAR-CCM+, Baseline 45-2x2
Baseline Krueger Drag
Drag Coefficient
Free Air CFD Corrected Tunnels
Angle of Attack 14x22, Baseline 45-2x2, r96 14x22 Sting, USM3D, Baseline 45-2x2 14x22 Sting, OVERFLOW, Baseline 45-2x2 14x22 Sting, STAR-CCM+, Baseline 45-2x2 No Krueger brackets modeled in CFD
Baseline Krueger with 14x22 Sting
Baseline Krueger Pitching Moment
Pitching Moment Coefficient
Free Air Free Air 14’x22’ Wind Tunnel Free Air 40’x80’ Wind Tunnel
Cruise • Baseline Krueger no brackets • • Acoustic Krueger w/brackets • •
CFD Configurations
HWB in LaRC 14’x22’
1000” to simulation outlet Side View View Cross Section HWB is ~83” long CFD Configuration used for 14’x22’ in STAR-CCM+ 1000” to simulation inlet
Wind Tunnel Walls
=25° Tunnel, Wake Box, and Sting Box, 82 Grids
OVERFLOW meshing layout used for LaRC 14’x22’
OVERFLOW Meshing
No Krueger brackets modeled in CFD
CFD with 14x22 Walls Uncorrected 14x22 Data
Angle of Attack 14x22, Corrected, Baseline 45-2x2, r96 In 14x22, OVERFLOW, Baseline 45-2x2 In 14x22, STAR-CCM+, Baseline 45-2x2 14x22, Uncorrected, Baseline 45-2x2, r96
Baseline Kreuger in 14'x22' Lift
Lift Coefficient No Krueger brackets modeled in CFD Angle of Attack 14x22, Corrected, Baseline 45-2x2, r96 In 14x22, OVERFLOW, Baseline 45-2x2 In 14x22, STAR-CCM+, Baseline 45-2x2 14x22, Uncorrected, Baseline 45-2x2, r96
CFD with 14x22 Walls Uncorrected 14x22 Data
Baseline Kreuger in 14'x22' Drag
Drag Coefficient Angle of Attack
CFD with 14x22 Walls Uncorrected 14x22 Data
14x22, Corrected, Baseline 45-2x2, r96 In 14x22, OVERFLOW, Baseline 45-2x2 In 14x22, STAR-CCM+, Baseline 45-2x2 14x22, Uncorrected, Baseline 45-2x2, r96 No Krueger brackets modeled in CFD
Baseline Kreuger in 14'x22' Pitching Moment
Pitching Moment Coefficient
Free Air Free Air 14’x22’ Wind Tunnel Free Air 40’x80’ Wind Tunnel
Cruise • Baseline Krueger no brackets • • Acoustic Krueger w/brackets • •
CFD Configurations
Krueger brackets modeled in CFD Angle of Attack
Free Air CFD Corrected Tunnels
14x22, Acoustic 45-3x2, r33 40x80, Acoustic 45-3x2, r23 40x80, Acoustic 45-3x2, R02 40x80 Sting, CFD++, Acoustic 45-3x2 40x80 Sting, OVERFLOW, Acoustic 45-3x2 40x80 Sting, STAR-CCM+, Acoustic 45-3x2
Acoustic Krueger Lift
Lift Coefficient Krueger brackets modeled in CFD
Free Air CFD Corrected Tunnels
Angle of Attack 14x22, Acoustic 45-3x2, r33 40x80, Acoustic 45-3x2, r23 40x80, Acoustic 45-3x2, R02 40x80 Sting, CFD++, Acoustic 45-3x2 40x80 Sting, OVERFLOW, Acoustic 45-3x2 40x80 Sting, STAR-CCM+, Acoustic 45-3x2
Acoustic Krueger Drag
Drag Coefficient Angle of Attack 14x22, Acoustic 45-3x2, r33 40x80, Acoustic 45-3x2, r23 40x80, Acoustic 45-3x2, R02 40x80 Sting, CFD++, Acoustic 45-3x2 Krueger brackets modeled in CFD 40x80 Sting, OVERFLOW, Acoustic 45-3x2 40x80 Sting, STAR-CCM+, Acoustic 45-3x2
Free Air CFD Corrected Tunnels
Acoustic Krueger Pitching Moment
Pitching Moment Coefficient
Free Air Free Air 14’x22’ Wind Tunnel Free Air 40’x80’ Wind Tunnel
Cruise • Baseline Krueger no brackets • • Acoustic Krueger w/brackets • •
CFD Configurations
HWB in NASA Ames 40’x80’
CFD HWB in ARC 40’x80’
STAR-CCM+
Krueger brackets modeled in CFD
CFD with 40x80 Walls Uncorrected 40x80 Data
Angle of Attack In 40x80, OVERFLOW, Acoustic 45-3x2 In 40x80, STAR-CCM+, Acoustic 45-3x2 40x80, Uncorrected values, Acoustic 45-3x2, r23 40x80, Uncorrected values, Acoustic 45-3x2, R02
Acoustic Krueger in 40'x80' Lift
Lift Coefficient Krueger brackets modeled in CFD
CFD with 40x80 Walls Uncorrected 40x80 Data
Angle of Attack In 40x80, OVERFLOW, Acoustic 45-3x2 In 40x80, STAR-CCM+, Acoustic 45-3x2 40x80, Uncorrected values, Acoustic 45-3x2, r23 40x80, Uncorrected values, Acoustic 45-3x2, R02
Acoustic Krueger in 40'x80' Drag
Drag Coefficient
CFD with 40x80 Walls Uncorrected 40x80 Data
Angle of Attack In 40x80, OVERFLOW, Acoustic 45-3x2 In 40x80, STAR-CCM+, Acoustic 45-3x2 40x80, Uncorrected values, Acoustic 45-3x2, r23 40x80, Uncorrected values, Acoustic 45-3x2, R02 Krueger brackets modeled in CFD
Acoustic Krueger in 40'x80' Pitching Moment
Pitching Moment Coefficient
CFD with Walls Uncorrected 40x80
CFD with Walls Uncorrected 40x80 Angle of Attack Arbitrary shift offset in Lift Free Air CFD Corrected 40x80
Free Air CFD Corrected 40x80
40x80, Acoustic 45-3x2, r23 40x80, Acoustic 45-3x2, R02 OVERFLOW, Acoustic 45-3x2 STAR-CCM+, Acoustic 45-3x2
Acoustic Krueger in 40'x80' Lift w/Free Air CFD
Lift Coefficient CFD with Walls Uncorrected 40x80 CFD with Walls Uncorrected 40x80 Angle of Attack Free Air CFD Corrected 40x80 Arbitrary shift offset in Drag 40x80, Acoustic 45-3x2, r23 40x80, Acoustic 45-3x2, R02 OVERFLOW, Acoustic 45-3x2 STAR-CCM+, Acoustic 45-3x2
Acoustic Krueger in 40'x80' Drag w/Free Air CFD
Drag Coefficient CFD with Walls Uncorrected 40x80 CFD with Walls Uncorrected 40x80 Free Air CFD Corrected 40x80 Angle of Attack 40x80, Acoustic 45-3x2, r23 40x80, Acoustic 45-3x2, R02 OVERFLOW, Acoustic 45-3x2 STAR-CCM+, Acoustic 45-3x2 Arbitrary shift offset in Pitching Moment
Acoustic Krueger in 40'x80' Pitching Moment w/Free Air CFD
Pitching Moment Coefficient ARC Sting Sting Sting 14’x22’ 14’x22’ 14’x22’ Tunnel 40’x80’ 40’x80’ Tunnel OVERFLOW ARC Sting Sting Sting Tunnel Tunnel 40’x80’ 14’x22’ 14’x22’ 40’x80’ 40’x80’ STAR-CCM+ Sting Sting CFD++ 40’x80’ 40’x80’ Boeing Sting Sting LaRC 14’x22’ 14’x22’ USM3D x x ARC 40’x80’ x x x LaRC 14’x22’ Cruise in Free Air Cruise in Tunnel Baseline Krueger 45°-2x2 in Free Air Baseline Krueger 45°-2x2 in Tunnel Acoustic Krueger 45-3x2 in Free Air Acoustic Krueger 45-3x2 in Tunnel
All data is for Freestream Mach = 0.2
Matrix of CFD and Tunnel Data
CFD simulations were performed before and after testing Used 4 different CFD codes 5.75% HWB scale model tested in the NASA LaRC 14’x22’ and NASA ARC 40’x80’ wind tunnels Good agreement with the measured results up to the stall Less agreement after the onset of stall Accurately modeled the vehicle in free air and with the wind tunnel walls