CFD methodology and validation for turbomachinery flows
Abstract
The essential problem today, in the application of 3D Navier-Stokes simulations to the design and analysis of turbomachinery components, is the validation of the numerical approximation and of the physical models, in particular the turbulence modelling. Although most of the complex 3D flow phenomena occurring in turbomachinery bladings can be captured with relatively coarse meshes, many detailed flow features are dependent on mesh size, on the turbulence and transition models. A brief review of the present state of the art of CFD methodology is given with emphasis on quality and accuracy of numerical approximations related to viscous flow computations. Considerations related to the mesh influence on solution accuracy are stressed. The basic problems of turbulence and transition modelling are discussed next, with a short summary of the main turbulence models and their applications to representative turbomachinery flows. Validations of present turbulence models indicate that none of the available turbulence models is able to predict all the detailed flow behavior in complex flow interactions. In order to identify the phenomena that can be captured on coarser meshes a detailed understanding of the complex 3D flow in compressor and turbines is necessary. Examples of global validations for different flow configurations, representative of compressor and turbine aerodynamics are presented, including secondary and tip clearance flows.
- Publication:
-
In AGARD
- Pub Date:
- May 1994
- Bibcode:
- 1994tduc.agar.....H
- Keywords:
-
- Approximation;
- Computational Fluid Dynamics;
- Discrete Functions;
- Flow Characteristics;
- Multigrid Methods;
- Navier-Stokes Equation;
- Proving;
- Space-Time Functions;
- Transition Flow;
- Turbomachinery;
- Turbulent Flow;
- Upwind Schemes (Mathematics);
- Viscous Flow;
- Compressor Blades;
- Computational Grids;
- Computer Aided Design;
- Computerized Simulation;
- Engine Design;
- K-Epsilon Turbulence Model;
- Mach Number;
- Pressure Distribution;
- Turbine Blades;
- Fluid Mechanics and Heat Transfer