UFR 3-31 Best Practice Advice

Flow over curved backward-facing step

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Description

Test Case Studies

Evaluation

Best Practice Advice

References

Best Practice Advice

Key Physics

The key physical features of this UFR that need to be correctly modelled are the position and the extent of the separation region. Both are very much a function of the performance of the model in three distinct regions: the turbulent boundary layer upstream of the separation (correct rise of turbulence level even upstream of nominal separation point), sufficient level of turbulent activity in the separated shear layer, and correct representation of the stabilizing effect of curvature to turbulence in separated shear layer.

Numerical Modelling

• Discretisation method
• Grids and grid resolution

Physical Modelling

• Turbulence modelling
• Transition modelling
• Near-wall modelling
• Other modelling

Application Uncertainties

Summarise any aspects of the UFR model set-up which are subject to uncertainty and to which the assessment parameters are particularly sensitive (e.g location and nature of transition to turbulence; specification of turbulence quantities at inlet; flow leakage through gaps etc.)

Recommendations for Future Work

Propose further studies which will improve the quality or scope of the BPA and perhaps bring it up to date. For example, perhaps further calculations of the test-case should be performed employing more recent, highly promising models of turbulence (e.g Spalart and Allmaras, Durbin's v2f, etc.). Or perhaps new experiments should be undertaken for which the values of key parameters (e.g. pressure gradient or streamline curvature) are much closer to those encountered in real application challenges.

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Contributed by: Sylvain Lardeau — CD-adapco

Front Page

Description

Test Case Studies

Evaluation

Best Practice Advice

References

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