need to be developed using the Massage Passing Interface MPI Standard to

Need to be developed using the massage passing

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need to be developed using the Massage Passing Interface (MPI) Standard to transfer data between different blocks. Post-processing: 1. Visualize the CFD results (contour, velocity vectors, streamlines, pathlines, streak lines, and iso-surface in 3D, etc.), and 2. CFD UA : verification and validation using EFD data (more details later) Post-processing usually through using commercial software
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27 Types of CFD codes Commercial CFD code : FLUENT, Star- CD, CFDRC, CFX/AEA, etc. Research CFD code : CFDSHIP-IOWA Public domain software (PHI3D, HYDRO, and WinpipeD, etc.) Other CFD software includes the Grid generation software (e.g. Gridgen, Gambit) and flow visualization software (e.g. Tecplot, FieldView) CFDSHIPIOWA
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28 CFD Educational Interface Lab1: Pipe Flow Lab 2: Airfoil Flow Lab3: Diffuser Lab4: Ahmed car 1. Definition of “CFD Process” 2. Boundary conditions 3. Iterative error 4. Grid error 5. Developing length of laminar and turbulent pipe flows. 6. Verification using AFD 7. Validation using EFD 1. Boundary conditions 2. Effect of order of accuracy on verification results 3. Effect of grid generation topology, “C” and “O” Meshes 4. Effect of angle of attack/turbulent models on flow field 5. Verification and Validation using EFD 1. Meshing and iterative convergence 2. Boundary layer separation 3. Axial velocity profile 4. Streamlines 5. Effect of turbulence models 6. Effect of expansion angle and comparison with LES, EFD, and RANS. 1. Meshing and iterative convergence 2. Boundary layer separation 3. Axial velocity profile 4. Streamlines 5. Effect of slant angle and comparison with LES, EFD, and RANS.
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29 CFD process Purposes of CFD codes will be different for different applications: investigation of bubble-fluid interactions for bubbly flows, study of wave induced massively separated flows for free-surface, etc. Depend on the specific purpose and flow conditions of the problem, different CFD codes can be chosen for different applications (aerospace, marines, combustion, multi-phase flows, etc.) Once purposes and CFD codes chosen, “ CFD process ” is the steps to set up the IBVP problem and run the code: 1. Geometry 2. Physics 3. Mesh 4. Solve 5. Reports 6. Post processing
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30 CFD Process Viscous Model Boundary Conditions Initial Conditions Convergent Limit Contours Precisions (single/ double) Numerical Scheme Vectors Streamlines Verification Geometry Select Geometry Geometry Parameters Physics Mesh Solve Post- Processing Compressible ON/OFF Flow properties Unstructured (automatic/ manual) Steady/ Unsteady Forces Report (lift/drag, shear stress, etc) XY Plot Domain Shape and Size Heat Transfer ON/OFF Structured (automatic/ manual) Iterations/ Steps Validation Reports
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31 Geometry Selection of an appropriate coordinate Determine the domain size and shape Any simplifications needed? What kinds of shapes needed to be used to best resolve the geometry? (lines, circular, ovals, etc.) For commercial code, geometry is usually created using commercial software (either separated from the commercial code itself, like Gambit, or combined together, like FlowLab) For research code, commercial software (e.g. Gridgen) is used.
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