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| AERO0004-1 | Turbulent Flow
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| Duration : | 30h Th, 30h Pr |
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| Number of credits : |
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| Lecturer : | Vincent Terrapon |
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Language(s) of instruction :
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| English language |
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Course contents :
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| The course is an introduction into turbulence in incompressible flows.
Its objective is to present the main characteristics of turbulent flows and how they differentiate themselves from laminar flows, to describe the different method of analysis used to treat turbulent flows, and to introduce numerical approaches and models that are frequently used in practice.
The course is divided in two parts. The first part explains the main features and properties of turbulent flows through dimensional analysis, physical intuition and statistical methods. In particular, following topics are covered:
- Difference between molecular and turbulent diffusion (mixing length, gradient-diffusion assumption, eddy viscosity)
- Statistical representation of turbulence (Reynolds-averaged equations; probability theory, means, variances and correlations; Reynolds-stress and closure problem)
- Scales in turbulent flows and their relation to the physics (energy cascade; Kolmogorov scaling)
- Dynamics of turbulence (kinetic energy; vorticity)
- Applications to canonical flows (free-shear flows; wall-bounded flows)
- Spectral analysis of turbulence
The second part of the course will focus on numerical methods that are used in practice to predict quantities of interest in turbulent flows:
- DNS - Direct numerical simulations
- RANS - Reynolds-Averaged Navier-Stokes models (algebraic models, two-equation models, Reynolds-stress models)
- LES - Large-eddy simulations (filtering, eddy viscosity)
The second part will heavily rely on properties and tools derived in the first part. |
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Learning outcomes of the course :
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| At the end of the course, the students should be able to:
- Know the major properties of turbulent flows, their sources and consequences
- Identify the relevant scales in specific configurations using dimensional analysis
- Use statistical tools to derive average equations, and to characterize and quantify turbulent flows
- Understand the role of the nonlinear terms in stability, energy transfer between scales and closure problem
- Derive the energy cascade and Kolmogorov scaling
- Understand the major differences between DNS, LES and RANS, and apply these numerical approaches in concrete situations
- Understand hypotheses, assumptions and simplifications in RANS models
- Know the differences between different RANS models, and their strengths and shortcomings
- Read and understand the classical literature on turbulence and more complex turbulence models
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Prerequisites and co-requisites/ Recommended optional programme components :
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| Basic knowledge in fluid mechanics (viscous flows, dimensional analysis, ...), in statistical theory (probability, correlation, ...), and in basic mathematics (Fourier transform, tensor algebra, ...) |
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Planned learning activities and teaching methods :
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| The theory is illustrated through regular exercises and a small project.
Exercises have the purpose to consolidate the material seen in class. They are therefore graded.
A small project at the end of the course gives the students the opportunity to apply some RANS models in a concrete case. This project requires the use of OpenFOAM. The grade is based on a written report and an oral presentation.
To be confirmed. |
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Mode of delivery (face-to-face ; distance-learning) :
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| The course is given in class. Exercises are done individually and independently by the students. |
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Recommended or required readings :
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| A copy of the slides presented in class is distributed electronically.
Required reading material:
- "Statistical Theory and Modeling for Turbulent Flows", P.A. Durbin & B.A. Pettersson Reif, 2nd edition
Recommended reading material and reference manuals:
- "Turbulent Flows", S.B. Pope
- "A First Course in Turbulence", H. Tennekes & J.L. Lumley
- "Turbulence Modeling for CFD", D.C. Wilcox
- "Statistical Fluid Mechanics - Mechanics of Turbulence", A.S. Monin & A.M. Yaglom
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Assessment methods and criteria :
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| The final grade for the course is based on
- Homework exercises: 30%
- Project written report: 40%
- Project oral presentation: 30%
To be confirmed. |
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Organizational remarks :
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| The course is taught in English |
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Contacts :
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| Prof. V. E. Terrapon
Phone: +32(0)4 366 9268
Email: vincent.terrapon@ulg.ac.be
http://www.mtfc.ulg.ac.be/ |
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