Keisuke Sawada. Department of Aerospace Engineering Tohoku University

Transcription

1 March 29th, 213 : Next Generation Aircraft Workshop at Washington University Numerical Study of Wing Deformation Effect in Wind-Tunnel Testing Keisuke Sawada Department of Aerospace Engineering Tohoku University

2 Outline 1. Brief description of numerical methods 2. AGARD-B static aeroelasticity analysis 3. ONERA-M5 static aeroelasticity analysis 4. Summary * All results are taken from Ph.D. thesis (21) written by Dr. Kanako Yasue who is now a researcher in Japan Aerospace Exploration Agency (JAXA)

3 CFD Solver Discontinuous Galerkin finite element method with second order of spatial accuracy Cellwise relaxation implicit time integration Hybrid unstructured mesh 1-eq. turbulence model (SA model) Parallel computation using MPI library

4 Static Aeroelasticity Analysis Method Loosely coupling approach Iteratively determine equilibrium shape Surface Mesh [Gridgen or TASmesh] Model Configuration Equilibrium Shape CFD Spatial Mesh [Gridgen or TASmesh] Surface Mesh Nodal Displacement CFD Analysis [DG solver] 3 5 iterations FEM Analysis [NX/NASTRAN ] Surface Pressure Distribution Nodal Loads : pre/post : main

5 AGARD-B Calibration Model Material: SUS34(wing) A224(body) unit=mm FEM model 4, nodes Quadratic element Hybrid grid (356,21 cells)

6 Equilibrium Wing Shape M =1.4, α=8.5º M =1.4, α=14.9º

7 Changes in Aerodynamic Coefficients M =1.4, p =167kPa (p =53kPa), T =273K (T =197K) Lift Coefficients Original geometry Deformed geometry Experiment ΔCL=.19 C L =.6765 C L =.6746 C L = Drag Coefficients Original geometry Deformed geometry Experiment ΔCD=.9 C D =.2315 C D =.236 C D =.244 C L.5 C D.15 C D =.166 C D =.155 ΔCD= C L =.49 C L =.41 C L =.41 ΔCL= α [deg].1.5 C D = α [deg]

8 ONERA-M5 Calibration Model unit=mm Material: SUS63 H175 CFD mesh FEM mesh 3.5M cells.5m nodes

9 Examined Conditions Re effect + Model deformation effect M =.84, α= 1.º Model deformation effect Re effect

10 Wing Deformation 3.5 Case 2 (Re=4M, P =22kPa) Case 3 (Re=1M, P =5kPa) Maximum displacement, mm Convergence histories of maximum displacement.5 Case 2 (Re=4M, Po=22kPa) Case 3 (Re=1M, Po=5kPa) Case 4 (Re=4M, Po=5kPa) Iterations Displacement Contours Case 4 (Re=4M, P =5kPa) Cp contours

11 Chord Line Deflections and Twist Angles Case 2 (Re=4M, P =22kPa) Case 3 (Re=1M, P =5kPa) Case 4 (Re=4M, P =5kPa) Bending (25% chord line) Bending (Max. thickness line) Bending (25% chord line) Bending (Max. thickness line) Bending (25% chord line) Bending (Max. thickness line) Deflection, mm Deflection, mm Deflection, mm Twist angle, deg Bending.2 twist.4 (25%.6chord.8 line) 1 Bending.2 twist.4 (25%.6chord.8 line) 1 Bending.2 twist.4 (25%.6chord.8 line) 1 Bending twist y/s (Max. thickness line) Bending twist y/s (Max. thickness line) Bending twist.2 y/s (Max. thickness line).2.2 Pure twist (25% chord line) Pure twist (25% chord line) Pure twist (25% chord line) Pure twist (Max. thickness line) Pure twist (Max. thickness line) Pure twist (Max. thickness line) Twist angle, deg -.1 Twist angle, deg y/s y/s y/s

12 Decomposition of CL and CD Pseudo Re effect ΔC L =-.39 ΔC D =-.42 Model deformation effect ΔC L =-.77 ΔC D =-.8 Re effect ΔC L = +.38 ΔC D =-.34

13 Summary Numerical methods Loosely coupled static aeroelasticity analysis method is successfully developed AGARD-B Even for moderate Re conditions, model deformation effect cannot be ignored for small aspect ratio delta wing ONERA-M5 Changes in aerodynamic coefficients are successfully decomposed into that caused by model deformation and that by Re effect