 | Hu N. Investigation of wall pressure fluctuations induced by turbulent boundary layer flow with pressure gradients: Diss. … Dr.-Ing.) / Deutsches Zentrum für Luft- und Raumfahrt, Institut für Aerodynamik und Strömungstechnik, Braunschweig. - Köln: DLR, 2018. - xiii,127 p.: ill., tab. - (Forschungsbericht; 2018-18). - Res. also Germ. - Bibliogr.: p.119-127.
- ISSN 1434-8454
Шифр: (Pr 1120/2918-18) 02
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Nomenclature ................................................... xi
1 Introduction ............................................... 1
1.1 Motivation and background .................................. 1
1.2 State of the art ........................................... 3
1.3 Scope and objectives ....................................... 7
1.4 Outline .................................................... 8
2 Fundamentals of wall pressure fluctuations beneath
turbulent boundary layers .................................. 9
2.1 Theoretical approaches ..................................... 9
2.1.1 Poisson's equation for pressure fiuctuatious
within boundary layers .............................. 9
2.1.2 Solutions to Poisson's equation .................... 11
2.2 Empirical uiodel approaches ............................... 14
2.2.1 One-point spectral model ........................... 14
2.2.2 Cross-spectral model ............................... 16
3 Methods ................................................... 19
3.1 Experimental test cases ................................... 19
3.1.1 Test setups ........................................ 19
3.1.2 Measurement techuiciues ............................ 21
3.2 Numerical approach ........................................ 24
3.2.1 Poisson's equation ................................. 24
3.2.2 Fast Random Particle-Mesh Method ................... 26
4 Experimental results ...................................... 33
4.1 Mean flow characteristics ................................. 33
4.2 One-point spectra ......................................... 36
4.3 Cross-spectra and convective velocities ................... 40
5 Formulation of an empirical model for one-point spectra ... 47
5.1 Parametric analysis and modification approach ............. 47
5.2 Comparison with published models .......................... 50
5.3 Validation of the proposed model .......................... 54
6 Numerical analysis ........................................ 69
6.1 Numerical verification and validation ..................... 69
6.1.1 Computational setup and flow parameters ............ 69
6.1.2 Turbulence velocity fluctuations realization ....... 70
6.1.3 One-point spectra .................................. 73
6.1.4 Root mean square pressure .......................... 79
6.1.5 Broadband correlations ............................. 79
6.1.6 Cross-spectra and phase velocities ................. 83
6.1.7 Wavenumber-frequency spectra ....................... 86
6.2 Application for different cases ........................... 88
6.2.1 Test cases and computational setups ................ 88
6.2.2 One-point spectra .................................. 93
6.2.3 Cross-spectra and convective velocities ............ 93
7 Conclusions and outlook .................................. 103
7.1 Conclusions .............................................. 103
7.2 Outlook .................................................. 105
A Temporal turbulence decay .................................. 109
B Wavenumber spectra of velocity fluctuations ................ 111
С Figures .................................................... 112
References .................................................... 119
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