Applications of CFD

Learning Outcomes

Subject Specific Practical Skills

Having successfully completed this module you will be able to:

• Describe likely levels of quality and trust associated with the analysis.
• Generate, adapt and assess high quality geometry and grids for a wide range of different applications
• Use a CFD package with an appreciation of modelling limitations, to demonstrate importance of validation and engineering interpretation of results;
• Solve basic equations of fluid dynamics using numerical methods;

Transferable and Generic Skills

Having successfully completed this module you will be able to:

• Understand basic numerical methods used in CFD analysis;
• Communicate work in written reports;
• Use commercial CFD packages to define, analyse, and solve a class of engineering problems;
• Study and learn independently.

Knowledge and Understanding

Having successfully completed this module, you will be able to demonstrate knowledge and understanding of:

• Fundamental CFD principles, including finite volume/difference methods, solvers of incompressible flows
• The latest research developments applicable to CFD
• The theoretical background (T,AE) and practical issues associated with the implementation of the use of CFD codes
• Basic principles of modelling curves/surfaces and generating grids;

Learning Outcomes

Having successfully completed this module you will be able to:

• C1/M1 In the 2nd assignment, the students are requested to demonstrate a good quality solution for the problem of 2D steady flow around an airfoil in turbulent flows at a moderate Reynolds number and moderate angles of attack, and provide supporting evidence for its quality. C2/M2 In the first assignment, the students are requested to analyse and implement numerical methods for the convective/diffusion problems for a pipe flow, and applied the sophisticated von Neumann stability analysis to determine the stability condition of the numerical method. C3 Both the two assignments require the student to choose appropriate numerical schemes in the computational fluid dynamics (CFD) software package for pipe flow and airfoil in turbulent flow problems. Demonstrating their understanding of the CFD is a key element of the assignments. C4/M4 The two assignments require the students to choose appropriate reference data (as well as reference papers) to validate their CFD solution, and make critical discussions on any discrepancies. C5/M5 The 2nd assignment requires students to design mesh refinement for a 2D wing considering the best practice of CFD and societal needs. C6 The 2nd assignment requires students to design mesh, using appropriate numerical schemes and turbulence models in an integrated manner (in a CFD software package) to provide a solution of aerodynamic forces and performance of a 2D wing, considering the balance of the accuracy and cost. C7 The 2nd assignment requires students require the students to estimate the lift and drag forces of a passenger aeroplane’s wing, therefore to ensure them being aware of the environmental impact and the approaches of mitigation. C12/M12 Every student is required to attend 11 mandatory and 1 optional computer labs, and to complete two assignments for one pipe flow, one 2D wing flow. C13/M13 To complete two assignments for one pipe flow, one 2D wing flow, the students are required to choose appropriate numerical schemes, turbulence models etc, considering their accuracy and computational cost. M14 The 2nd assignment (for a 2D wing) requires the students to assess the performance of turbulence model, and to demonstrate how to manage the quality of estimation using the software package. C15/M15 The 2nd assignment (for a 2D wing) requires students to estimate the computational cost for aerodynamic forces of a full-scale passenger aeroplane wing, and therefore to suggest required resources for these computations. C18/M18 Applications of CFD (FEEG6005) has a focus of using CFD software package to solve applied problems (such as pipe flows, wing flows), which provides intrinsic functionality for student’s self-learning. A CFD Surgery Blackboard, which is a complementary Blackboard for student’s self-learning, provides broader and deeper CFD materials for student’s life-long learning.

Overview of CFD and fundamental of fluids (4 lectures)

• What is CFD, Continuity equation, Navier-Stokes & RANS equations, numerical techniques in

CFD,geometry and mesh, data visualization, validation, examples of applications.

Boundary layer theory/Two phase flow (2 lectures)

• Boundary layer: background of boundary layer theory, law of the wall, flow separation.
• Two phase flow: basic physicsandtwo-phase flow applications, two-phase flow regimes, volume of fluid (VOF) model, heat/scalar transport equation.

Numerical Procedures in CFD (8 lectures)

• Physical flow vs numerical methods, classification of fluid flow equations, finite difference methods, finite volume method, explicit and implicit schemes, properties of numerical methods, solution

procedure.

Geometry and grid generation (6 hours)

• Curve and surface generation. Structured/unstructured grid generation. Grid adaption to flows, e.g. boundary layer mesh. Dynamics mesh.

Introduction to using CFD solvers in packages (6 hours)

• Review of pressure solvers (e.g. SIMPLE, PISO) for incompressible flows and how they are implemented in typical commercial packages. Examination of various numerical schemes and flow

solver strategies available in CFD packages. Practical tips for successful calculations and resolving non-convergence problems.

• User programming in CFD packages.

Practical turbulence modelling (6 hours)

• Derivation of typical one/two-equation turbulence models.

Theoretical basis of available turbulence models within CFD solvers. Examination of their strengths and weaknesses when applied to practical engineering problems. The importance of turbulence model choice on accuracy of solution. Comparison with alternative models considering strengths/weaknesses and consideration of future

developments such as LES.

Interpretation of results (2 hours)

• The quality, confidence and trust that can be applied to the results of CFD analysis. Examples of typical validation studies.

Revision (2 lecture)

Computing Lab Sessions: 2 Assignments (2 hours/week throughout Semester 1)

• Assignment 1: Simulation & accuracy of convection and diffusion problems using numerical methods.
• Assignment 2. Geometry and grid generation, and RANS solutions of airfoils at a range of incidences up to near stall or stall using a CFD package.

Teaching methods include

• Lectures (3/week)
• A computing lab session (1/week)
• Blackboard tutorials.

Summative

This is how we’ll formally assess what you have learned in this module.

Referral

This is how we’ll assess you if you don’t meet the criteria to pass this module.

Repeat

An internal repeat is where you take all of your modules again, including any you passed. An external repeat is where you only re-take the modules you failed.