 | Fehrs M. Boundary layer transition in external aeurodynamics and dynamic aeroelastic stability: Diss. … Dr.-Ing. /
Deutsches Zentrum für Luft- und Raumfahrt, Institut fur Aeroelastik, Göttingen. – Köln: DLR, 2018. - xvi, 143 p.: ill., tab. - (Forschungsbericht; 2018-11). - Res. also Germ. - Bibliogr.: p.131-142.
- ISSN 1434-8454
Шифр: (Pr 1120/2018-11) 02
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1 Introduction ............................................... 1
1.1 Motivation and Scope ....................................... 1
1.2 Scientific Background ...................................... 2
1.2.1 Transition and Aerodynamics ......................... 2
1.2.2 Transition and Aeroelasticity ....................... 4
2 Boundary Layer Transition .................................. 7
2.1 Transition Process ......................................... 7
2.2 Receptivity ................................................ 7
2.3 Transition Mechanisms ...................................... 9
2.3.1 Tollmien-Schlichting Transition ..................... 9
2.3.2 Bypass Transition .................................. 10
2.3.3 Separated-Flow Transition .......................... 11
2.3.4 Crossflow Transition ............................... 12
2.3.5 Attachment Line Transition ......................... 13
2.3.6 Relaminarization ................................... 14
2.4 Transition Zone Length and Intermittency .................. 15
2.5 Influence Parameters on Transition ........................ 16
2.5.1 Overview of Parameters ............................. 16
2.5.2 Freestream Turbulence Level ........................ 17
2.5.3 Pressure Gradient .................................. 19
2.5.4 Compressibility .................................... 21
2.6 Unsteady Boundary Layer Transition ........................ 22
3 Aeroelasticity ............................................ 25
3.1 Dynamic Aeroelastic Stability: Flutter .................... 25
3.2 Unsteady Aerodynamics ..................................... 26
3.3 Flutter Solution for a Binary System ...................... 28
4 Transition Model .......................................... 31
4.1 7-Re9 Transition Model .................................... 31
4.1.1 Local Correlation-Based Transition Model ........... 31
4.1.2 Transition Model Description ....................... 32
4.1.3 Transition Model Deficiencies ...................... 36
4.2 7 Transition Model ........................................ 40
4.2.1 Transition Model Description ....................... 40
4.2.2 Transition Criterion ............................... 43
4.2.3 Compressibility Correction ......................... 4b
4.2.4 Transition Model Calibration ....................... 48
5 Results ................................................... 53
5.1 Flat Plate Test Cases ..................................... 53
5.1.1 Bennett (1953) ..................................... 53
5.1.2 Schubauer and Klebanoff (1955) ..................... 55
5.1.3 ERCOFTAC T3 Series ................................. 57
5.1.4 Grid Dependency: Flat Plate ........................ 64
5.2 Steady Airfoil Test Cases ................................. 66
5.2.1 NLR 7301 ........................................... 66
5.2.2 NACA 65(215)-114 ................................... 79
5.2.3 NLF(1)-0414F ....................................... 83
5.2.4 NLF(2)-0415M ....................................... 86
5.2.5 Grid Dependency: Airfoil ........................... 89
5.3 Steady Wing Test Case ..................................... 91
5.4 Unsteady Airfoil Test Cases ............................... 93
5.4.1 CAST10-2: Unsteady Validation ...................... 93
5.4.2 NLF(2)-0415M: γ Model and eN Method ............... 102
5.4.3 NLF(2)-0415M: Laminar Airfoil ..................... 106
5.4.4 RAE 2822: Supercritical Airfoil ................... 116
6 Conclusion ............................................... 129
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