1. Computer Aided Thermal Fluid Analysis Lecture 2 Dr. Ming-Jyh Chern ME NTUST

2. Road Map for Today How to initialize STAR-CD? How to initialize STAR-CD? Four major modeling processes. Four major modeling processes. Usage of SET Usage of SET Generation of Vertices Generation of Vertices

3. prostar - Exceed STAR-CD was coded under an X-window environment. STAR-CD was coded under an X-window environment. To run STAR-CD in MS Window, a program to transform images given by STAR-CD is necessary. To run STAR-CD in MS Window, a program to transform images given by STAR-CD is necessary. Exceed is able to reach this goal. You need to run exceed before the usage of STAR-CD. Exceed is able to reach this goal. You need to run exceed before the usage of STAR-CD.

4. STAR-CD Launcher

5. prostar - Exceed

6. prostar

7. Command Window

8. STAR-GUIDE

9. Quit from STAR-CD

10. Four Major Modeling Process Phase 1 – Working out a modeling strategy Phase 1 – Working out a modeling strategy Phase 2 – Preprocessing - Setting up the flow model using PROSTAR Phase 2 – Preprocessing - Setting up the flow model using PROSTAR Phase 3 – Solver - Performing the flow analysis using STAR Phase 3 – Solver - Performing the flow analysis using STAR Phase 4 – Post-processing the results using PROSTAR Phase 4 – Post-processing the results using PROSTAR

11. Phase 1 – Working out a Modeling Strategy Planning the computational mesh Planning the computational mesh Looking up numerical values for appropriate physical parameters Looking up numerical values for appropriate physical parameters Choosing the most suitable modeling option from what is available. Choosing the most suitable modeling option from what is available.

12. Phase 2 – Setting Up the Flow Model Using Prostar Creating a computational mesh to represent the flow domain. Creating a computational mesh to represent the flow domain. Specifying the thermophysical properties of the fluids and/or solids. Specifying the thermophysical properties of the fluids and/or solids. Setting the solution parameters and output data formats. Setting the solution parameters and output data formats. Specifying the location and definition of boundaries and time increment. Specifying the location and definition of boundaries and time increment. Writing appropriate data files. Writing appropriate data files.

13. Phase 3 – Performing the Flow Analysis Using Prostar Reading input data created by Prostar and, if dealing with a restart run, the results of a previous run. Reading input data created by Prostar and, if dealing with a restart run, the results of a previous run. Judging the progress of the run by analysing various monitoring data and solution statistics provided by STAR. Judging the progress of the run by analysing various monitoring data and solution statistics provided by STAR.

14. Phase 4 – Post- processing the results Using Prostar Display and visualize the obtained results. Display and visualize the obtained results. Plot velocity vector fields. Plot velocity vector fields. Plot contours regarding pressure, density and so on. Plot contours regarding pressure, density and so on. Plot curves regarding variation of flow fields. Plot curves regarding variation of flow fields.

15. STAR-CD System Structure

16. Pro-STAR

17. STAR

18. Files in STAR-CD

19. Usage of Mouse Left bottom – Rotation Left bottom – Rotation Middle bottom (or Left+Right bottoms) – Zoom Middle bottom (or Left+Right bottoms) – Zoom Right bottom - Move Right bottom - Move

20. Basic Elements Cell Cell Vertex Vertex Boundary Boundary Block Block Couple Couple Spline Spline Droplet Droplet

21. Concept of Set Every command or action in STAR-CD only affects elements in a set. Before you give a command, you ’ d better select the elements which you want to modify. Every command or action in STAR-CD only affects elements in a set. Before you give a command, you ’ d better select the elements which you want to modify. The range of a set can be checked via “ List ” in Prostar. The range of a set can be checked via “ List ” in Prostar.

22. When set is used? Plot results Plot results Establish model Establish model Check model Check model Post-processing Post-processing

23. Common sets cset: Cell set cset: Cell set vset: Vertex set vset: Vertex set bset: Boundary set bset: Boundary set splset: Spline set splset: Spline set Blkset: Block set Blkset: Block set

24. Coordinates Global coordinate Global coordinate Local coordinate Local coordinate Cartesian coordinate Cartesian coordinate Cylindrical coordinate Cylindrical coordinate Spherical coordinate Spherical coordinate

25. Coordinates Change or view setting of coordinate system from STAR GUIde. Change or view setting of coordinate system from STAR GUIde. Create and Import Geometry->Create Geometric Entities-> find vertices in the yellow part-> click the icon near “ Current Coordinate System ” Create and Import Geometry->Create Geometric Entities-> find vertices in the yellow part-> click the icon near “ Current Coordinate System ”

26. Coordinates Current system

27. Command For Vertex Generation Before you generate a vertex, you ’ d better to check which coordinate you use. Before you generate a vertex, you ’ d better to check which coordinate you use. v,1,0,0,5 v,1,0,0,5 v,2,10,0,0 v,2,10,0,0 vset,all vset,all vplot vplot

28. Alternative Way to Generate a Vertex

29. Vertex List Find vertex list from the item “ Vertices ” of “ Lists ” in Prostar Find vertex list from the item “ Vertices ” of “ Lists ” in Prostar

30. Vertex Tool Find vertex tool from the item “ Vertex Tool ” of “ Tools ” in Prostar Find vertex tool from the item “ Vertex Tool ” of “ Tools ” in Prostar

31. Vertex Tool