Peng / Haase Advances in Hybrid RANS-LES Modelling

Papers contributed to the 2007 Symposium of Hybrid RANS-LES Methods, Corfu, Greece, 17-18 June 2007
1. Auflage 2008
ISBN: 978-3-540-77815-8
Verlag: Springer Berlin Heidelberg
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 334 Seiten

Reihe: Notes on Numerical Fluid Mechanics and Multidisciplinary Design

Turbulence modelling has long been, and will remain, one of the most important t- ics in turbulence research, challenging scientists and engineers in the academic world and in the industrial society. Over the past decade, Detached Eddy Simulation (DES) and other hybrid RANS-LES methods have received increasing attention from the turbulence-research community, as well as from industrial CFD engineers. Indeed, as an engineering modelling approach, hybrid RANS-LES methods have acquired a remarkable profile in modelling turbulent flows of industrial interest in relation to, for example, transportation, energy production and the environment. The advantage exploited with hybrid RANS-LES modelling approaches, being - tentially more computationally efficient than LES and more accurate than (unsteady) RANS, has motivated numerous research and development activities. These activities, together with industrial applications, have been further facilitated over the recent years by the rapid development of modern computing resources. As a European initiative, the EU project DESider (Detached Eddy Simulation for Industrial Aerodynamics, 2004-2007), has been one of the earliest and most systematic international R&D effort with its focus on development, improvement and applications of a variety of existing and new hybrid RANS-LES modelling approaches, as well as on related numerical issues. In association with the DESider project, two subsequent international symposia on hybrid RANS-LES methods have been arranged in Stockholm (Sweden, 2005) and in Corfu (Greece, 2007), respectively. The present book is a result of the Second Symposium on Hybrid RANS-LES Methods, held in Corfu, Greece, 17-18 June 2007.

Autoren/Hrsg.

Peng, Shia-Hui

Haase, Werner

Inhaltsverzeichnis

1;Preface;7
2;Table of Contents;9
3;The 2007 Hybrid RANS-LES Symposium: An Outsider’s View;13
3.1;Generalities;13
3.2;The Wider Exercise of DES;14
3.3;Neighbouring Concepts;17
3.4;Scale-Adaptive Simulation;18
3.5;Separate Issues in Complex Flows;18
3.6;Wall Modelling;19
3.7;Pure LES Studies;19
3.8;Outlook;20
3.9;References;21
4;Reliability of LES in Complex Applications;22
4.1;Introduction;22
4.2;Database Approach to Interacting Errors;24
4.3;Iterative Approximation of the Optimal Smagorinsky Constant;28
4.4;Concluding Remarks;30
4.5;References;32
5;Turbulent Eddies in the RANS/LES Transition Region;33
5.1;Introduction;33
5.2;Problem Formulation;35
5.3;WMLES Using Hybrid Methods;35
5.4;Zonal LES;40
5.5;Conclusions;46
5.6;References;46
6;Uncertainty Modeling, Error Charts and Improvement of Subgrid Models;49
6.1;Statement of the Problem;49
6.2;Inertial Range Consistent Subgrid/Turbulence Models;49
6.2.1;The Concept of Robust Modelling;51
6.2.2;Copping with Uncertainties: Response Surface;53
6.3;Concluding Remarks;55
7;Hybrid LES-RANS Method Based on an Explicit Algebraic Reynolds Stress Model;57
7.1;Introduction;57
7.2;Hybrid LES-RANS Method;57
7.3;LES-RANS Interface;59
7.4;Numerical Methodology and Test Cases;59
7.5;Results for Channel Flow at $Re_{tau}$ = 590;60
8;Hybrid LES-RANS: Inlet Boundary Conditions for Flows with Recirculation;67
8.1;Introduction;67
8.2;Synthesized Turbulence;68
8.3;The Numerical Method;69
8.4;The Hybrid LES-RANS Model;69
8.5;Results;69
8.6;Conclusions;76
8.7;References;77
9;On the Use of Stimulated Detached Eddy Simulation (SDES) for Spatially Developing Boundary Layers;79
9.1;Introduction;79
9.2;Turbulence Modeling;80
9.2.1;Natural Use of DES, Grey Area Topic;80
9.2.2;Motivation of Stimulated DES;80
9.3;Computational Geometry and Indicators;81
9.3.1;Test Case;81
9.3.2;Indicators;82
9.4;Results and Discussion;82
9.4.1;Precursor Calculation;82
9.4.2;Recycling Method;84
9.4.3;Synthetic Turbulence;85
9.5;Conclusion;87
9.6;References;88
10;Synthetic Inflow Boundary Conditions for Wall Bounded Flows;89
10.1;Introduction;89
10.2;Governing Equations and Numerical Method;90
10.2.1;Governing Equations;90
10.2.2;Synthetic Eddy Method;91
10.3;Optimal Synthetic Inflow Boundary Conditions for LES;92
10.4;Hybrid RANS-LES Results;94
10.4.1;Synthesized Turbulence;94
10.4.2;Boundary Layer Results;95
10.4.3;Other Types of Wall Bounded Flows Results;97
10.5;Conclusions;97
10.6;References;98
11;X-LES Simulations Using a High-Order Finite-Volume Scheme;99
11.1;Introduction;99
11.2;The X-LES Method;100
11.3;High-Order Finite-Volume Method;101
11.4;Flow over a Rounded Bump in a Square Duct;101
11.5;Supersonic Flow over a Cavity;105
11.6;Conclusions;108
11.7;References;108
12;One-Equation RG Hybrid RANS/LES Modelling;109
12.1;Introduction;109
12.2;The Model;110
12.3;Simulation Set up;111
12.4;Impinging Jet;111
12.4.1;Nozzle-Plate Distance 2D;111
12.4.2;Nozzle-Plate Distance 6D;114
12.4.3;Plane Asymmetric Diffuser;114
12.5;Conclusion;116
12.6;References;117
13;Scrutinizing Velocity and Pressure Coupling Conditions for LES with Downstream RANS Calculations;119
13.1;Introduction;119
13.2;Turbulence Models and Numerical Method;120
13.3;Velocity Coupling;120
13.4;Pressure Coupling;122
13.5;Turbulent Channel Flow;123
13.6;Periodic Hill Flow;126
13.7;Conclusions;128
13.8;References;128
14;Computation of the Helicopter Fuselage Wake with the SST, SAS, DES and XLES Models;129
14.1;Test Case Description;129
14.2;Partners, Numerical Tools, Grids and Computations;130
14.3;Results;132
14.3.1;Global Loads;132
14.3.2;Cp-Distribution;133
14.3.3;Oil Flow;134
14.4;Conclusion;136
14.5;References;136
15;Numerical Simulation of the Flow in the Wake of Ahmed Body Using Detached Eddy Simulation and URANS Modeling;137
15.1;Introduction;137
15.2;DES Modelling;138
15.3;DDES Modelling;138
15.4;Numerical Configuration;139
15.5;Results;139
15.5.1;URANS Computations on Both Configurations;139
15.5.2;DES and DDES Results;141
15.6;Conclusion and Prospects;142
15.7;References;143
16;DES and Hybrid RANS-LES Modelling of Unsteady Pressure Oscillations and Flow Features in a Rectangular Cavity;144
16.1;Introduction;144
16.2;Simulation Approaches;145
16.3;Results and Discussion;147
16.3.1;Predictions of Pressure Oscillations;148
16.3.2;Flow Features in the Cavity;150
16.4;Conclusions;152
16.5;References;153
17;Comparative Assessment of Hybrid LES/RANS Models in Turbulent Flows Separating from Smooth Surfaces;154
17.1;Introduction;154
17.2;Computational Method;155
17.3;Results and Discussion;156
17.3.1;Flow over a Wall-Mounted Hump;156
17.3.2;Periodic Flow over a 2-D Hill;160
17.4;Conclusions;162
17.5;References;162
18;Numerical Investigation of a Laboratory Combustor Applying Hybrid RANS-LES Methods;164
18.1;Introduction;164
18.2;Physical Models;165
18.2.1;Conservation Equations;165
18.2.2;Turbulence Modelling;165
18.3;Results and Discussion;167
18.3.1;Test Case;167
18.3.2;Numerical Setup;168
18.3.3;Averaged Profiles;168
18.3.4;Unsteady Analysis;171
18.4;Conclusions;172
18.5;References;173
19;DES of a Cavity with Spoiler;174
19.1;Introduction;174
19.2;Experimental Test Cases;174
19.2.1;Configurations;174
19.2.2;Experimental Data;175
19.3;Computations;175
19.3.1;Introduction;175
19.3.2;Model;175
19.3.3;Geometry and Computational Domain;175
19.3.4;Mesh;176
19.3.5;Boundary Conditions;177
19.3.6;Numerical Scheme;177
19.4;Post Processing;177
19.5;Results;178
19.5.1;Sound Pressure Levels;178
19.5.2;Pressure Variance;179
19.5.3;Pressure Contours;180
19.5.4;Vorticity Contours;181
19.5.5;Q Criterion;182
19.6;Conclusions;182
19.7;References;183
20;DES Analysis of Confined Turbulent Swirling Flows in the Sub-critical Regime;184
20.1;Introduction;184
20.2;Experimental;185
20.3;Modelling;185
20.4;The Computational Grid;187
20.5;Inlet Boundary Conditions;187
20.6;Results;188
20.7;Conclusions;192
20.8;References;192
21;Zonal-Detached Eddy Simulation of Transonic Buffet on a Civil Aircraft Type Configuration;194
21.1;Introduction;194
21.2;Turbulence Modelling;195
21.3;Test Case;195
21.4;Numerical Methods;196
21.5;Z-DES Grid on the CAT3D Model and Boundary Conditions;197
21.6;Results and Discussion;198
21.7;Conclusion;202
21.8;References;202
22;Detached Eddy Simulation of Separated Flow on a High-Lift Device and Noise Propagation;204
22.1;Introduction - The FREQUENZ Campaign;204
22.2;The FLOWer Code;204
22.3;Turbulence Modelling;205
22.3.1;The Spalart-Allmaras One Equation Model;205
22.3.2;Large Eddy Simulation (LES);205
22.3.3;The DES Approach;206
22.4;Noise Propagation;206
22.5;Simulations;206
22.5.1;Numerical and Experimental Setup;207
22.5.2;Flow Characteristics;209
22.5.3;The Law of the Wall;209
22.5.4;Velocity Correlations;210
22.5.5;Investigation of the Profile Wake;210
22.5.6;Nearfield Noise;212
22.6;Conclusion;213
22.7;References;213
23;Unsteady CFD Analysis of a Delta Wing Fighter Configuration by Delayed Detached Eddy Simulation;214
23.1;Introduction;214
23.2;Numerical Tools;215
23.2.1;Description of the Flow Solver;215
23.2.2;DES97;216
23.2.3;Delayed DES;217
23.3;Flow Conditions and Computational Grid;217
23.4;DES97 and Delayed DES Results;218
23.5;Conclusions;222
23.6;References;223
24;Comparison of DES and LES on the Transitional Flow of Turbine Blades;224
24.1;Introduction;224
24.2;Computational Setup;225
24.2.1;Non-reflecting Boundary Condition;225
24.2.2;SEM for Compressible Flows;226
24.2.3;High-Pass Filtered Smagorinsky Model;226
24.2.4;Hybrid RANS-LES Modelling;227
24.3;Results;227
24.4;Conclusions;232
24.5;References;232
25;Demonstration of Improved DES Methods for Generic and Industrial Applications;234
25.1;Introduction;234
25.2;Numerical Method;234
25.3;DES Investigation and Validation;235
25.3.1;Validation of DES for Bluff Body Flows with Massive Separation;235
25.3.2;Model Sensitivity of DES;236
25.3.3;The “Grey Area” and Alternative Length-Scale Substitutions;237
25.3.4;Behaviour of RANS Model Damping Terms;237
25.3.5;Modelled Stress Depletion and Grid-Induced Separation;238
25.3.6;DES as Wall Model for LES of Attached Boundary Layers;239
25.4;Demonstration on the Basis of Industrially-Relevant Applications;240
25.4.1;Effectiveness of GIS-Shield and $Psi$ Functions for Slat Cove Noise Prediction;240
25.4.2;Reduction of Grey Area for Coaxial Jet Noise Prediction;240
25.4.3;Boundary Layer and Trailing Edge Airfoil Noise Using Wall-Modelled LES;241
25.5;Conclusion;242
25.6;References;243
26;Towards a Successful Implementation of DES Strategies in Industrial RANS Solvers;244
26.1;Introduction;244
26.2;Code Description;244
26.3;DES Modeling;245
26.4;Adaptation to LES;245
26.5;Results on Complex Geometries;247
26.5.1;Aerofoil with a High Angle of Attack;247
26.5.2;The DESider Bump;249
26.5.3;The Ahmed Body with a 25^{o} Slant Angle;250
26.6;Concluding Remarks;252
26.7;References;252
27;Delayed Detached-Eddy Simulation of Supersonic Inlet Buzz;254
27.1;Introduction;254
27.2;Experimental Data;255
27.3;Numerical Method;257
27.3.1;Grid;257
27.3.2;The DDES Method;257
27.4;Simulation of Buzz;260
27.5;Conclusion;262
27.6;References;262
28;DES Applied to an Isolated Synthetic Jet Flow;264
28.1;Introduction;264
28.2;\~d vs d;265
28.3;Computational Techniques;265
28.4;Test Case and Results;267
28.4.1;The SJ Configuration and the Grid;267
28.4.2;Vortical Features of the Periodic Flow Field;268
28.4.3;Time Averaged Jet Velocities;268
28.4.4;Phase Averaged Analysis;269
28.5;Discussions and Summary;271
28.6;References;272
29;Development and Application of SST-SAS Turbulence Model in the DESIDER Project;273
29.1;Introduction of the Scale-Adaptive Simulation Concept;273
29.2;SST-SAS Turbulence Model;274
29.3;Validation of the SST-SAS Model for the Aerodynamic Applications;277
29.3.1;NACA0021 Airfoil Beyond Stall;277
29.3.2;Delta Wing;279
29.3.3;Full Aircraft FA-5 Configuration;279
29.3.4;3-D Acoustic Cavity;281
29.4;References;282
30;Numerical Simulation of the Dynamic Stall of a NACA 0012 Airfoil Using DES and Advanced OES/URANS Modelling;283
30.1;Introduction;283
30.2;Turbulence Modelling;283
30.2.1;Macrosimulation Approaches for Unsteady Flows;283
30.2.2;DES Modelling;286
30.3;Physical Analysis of the Dynamic Stall Around a Pitching Airfoil at 10^6 Reynolds Number;287
30.3.1;Two-Dimensional Computations;287
30.3.2;Three Dimensional Computations;289
30.4;Conclusion and Prospects;289
30.5;References;290
31;Turbulence Modelling of Strongly Detached Unsteady Flows: The Circular Cylinder;291
31.1;Introduction;291
31.2;The Stress-Strain Lag Model;292
31.2.1;The SST-C_{as} Model;293
31.3;Case Details;294
31.4;Results;294
31.5;Conclusions;299
31.6;References;300
32;A New Variant of Subgrid Dissipation for LES Method and Simulation of Laminar-Turbulent Transition in Subsonic Gas Flows;301
32.1;Quasi-Gasdynamic Equations;301
32.2;Numerical Algorithm;303
32.3;Backward-Facing Step Flow Calculations;303
32.4;Conclusions;310
32.5;References;310
33;Formulation of Subgrid Stochastic Acceleration Model (SSAM) for LES of a High Reynolds Number Flow;311
33.1;Motivation;311
33.2;Model-Equation in LES-SSAM;313
33.3;Stochastic Model of the Non-resolved Acceleration;313
33.4;Computation of 3D Stationary Box Turbulence;314
33.5;Conclusions;316
33.6;References;316
34;Flow Around a Surface-Mounted Finite Cylinder: A Challenging Case for LES;317
34.1;Introduction;317
34.2;Description of the Set-Up;318
34.3;Computational Mesh and Numerical Details;318
34.4;Results;319
34.4.1;Instantaneous Flow;319
34.4.2;Vortex Shedding;320
34.4.3;The Horseshoe Vortex;322
34.4.4;Downwash Flow;323
34.4.5;Far-Wake Flow;324
34.4.6;Time-Averaged Flow;325
34.5;Conclusions;326
34.6;References;327
35;Compressibility Effects on Turbulent Separated Flow in a Streamwise-Periodic Hill Channel –– Part 2;328
35.1;Introduction;328
35.2;Results;330
35.3;Conclusions;336
35.4;References;337
36;Author Index;339
37;Addresses of Corresponding Authors;341