OpenFOAM/C2/Creating-curved-geometry-in-OpenFOAM/English-timed
From Script | Spoken-Tutorial
| Time | Narration |
| 00:01 | Hello and welcome to the spoken tutorial on Creating Curved geometry in OpenFOAM. |
| 00:06 | In this tutorial, I will show you: |
| 00:09 | Steps for creating a curved geometry in openfoam. |
| 00:14 | Viewing the results in paraview |
| 00:17 | To record this tutorial, |
| 00:19 | I am using: Linux Operating system Ubuntu version 10.04, OpenFOAM version 2.1.0 |
| 00:28 | ParaView version 3.12.0. |
| 00:32 | The tutorials were recorded using the versions specified in previous slide. Subsequently the tutorials were edited to latest versions. To install latest system requirements go to Installation Sheet |
| 00:37 | We will create a geometry for flow over a cylinder. |
| 00:41 | Note that I am using this case just for explanation. |
| 00:46 | The cylinder is in the form of a semi circle. |
| 00:50 | Meshing is a body fitted grid. |
| 00:54 | The entire geometry is divided into blocks. |
| 00:59 | We break the semi circle into equal number of parts. |
| 01:03 | Now minimize this. |
| 01:08 | Open a 'blockMeshDict' file of the previous tutorial. |
| 01:13 | I have already opened it. |
| 01:17 | Scroll down. For simple geometries, you can see that edges is kept empty. |
| 01:25 | Now Create a new 'blockMeshDict' file. |
| 01:28 | To do this, let us minimize this first. |
| 01:32 | Now, right-click > create document > empty file. |
| 01:39 | Name this as 'blockMeshDict'. |
| 01:45 | Note that M and D here are capital. |
| 01:51 | Open this. |
| 01:56 | Now you can copy the initial few lines from the 'lid driven cavity' up to 'convertTometers'. |
| 02:03 | Go up, copy this up to 'convertToMeters'. |
| 02:09 | Copy this and paste it in the new 'blockMeshDict' file. |
| 02:17 | Now, change the 'convert to meters' from point one to one. |
| 02:23 | As our geometry is in meters, we will keep this as one. |
| 02:29 | Now press Enter , press Enter again. |
| 02:33 | After this, you need to enter the co-ordinates of the geometry in vertices. |
| 02:40 | Let me switch back to the slide. Note that the points should be ordered in such a way starting from 0, 1, 2, 3, 4 and so on, as shown in the figure. |
| 02:52 | Minimize the slide. Now, type "vertices" in the 'blockMeshDict' file and press Enter. |
| 03:01 | Insert the open bracket and press Enter. |
| 03:05 | Now enter the co-ordinates of the geometry as shown in the diagram. |
| 03:10 | Let me switch back to the slides. |
| 03:13 | For explanation, I will use right half of the semi-circle. |
| 03:17 | Enter the values for the points in the figure starting from 0. |
| 03:21 | Let me switch back to the 'blockMeshDict' file. |
| 03:25 | Leave some space and enter the co-ordinates of point 0. |
| 03:32 | Open close bracket enter 0.5 (space) 0 (space) 0. Press Enter. |
| 03:41 | Again leave some space , open close bracket. |
| 03:44 | Enter the co-ordinates for point 1 (space) 0 (space) 0. Press Enter. |
| 03:50 | Now leave two vertical spaces, again press Enter, again press Enter. |
| 03:56 | Leave some space and enter the co-ordinates for point number 4. |
| 04:02 | Open close bracket, enter 0.707 (space) 0.707 (space) 0 |
| 04:10 | Press Enter. Leave some space. |
| 04:14 | Open close bracket.Enter the co-ordinates for the point 5. |
| 04:18 | Enter 0.353 (space) 0.353 (space) 0, press Enter. |
| 04:27 | Now, leave 4 vertical spaces and enter co-ordinates for point number 9. |
| 04:32 | 1 2 3 4 , again press Enter, leave some space. |
| 04:37 | Open, close bracket. |
| 04:41 | Enter 0 (space) 1 (space) 0, press Enter. |
| 04:47 | Leave some space. |
| 04:48 | Enter the co-ordinates for point number 10. |
| 04:49 | Open close bracket 0 (space) 0.5 (space) 0 press Enter. |
| 04:57 | Similarly enter the co-ordinates for the remaining points in the geometry. |
| 05:03 | Insert a close bracket put a semi-colon and press Enter. |
| 05:08 | Again press Enter.Now, type "blocks", press Enter. |
| 05:16 | Insert an open bracket, press Enter. |
| 05:19 | Let me switch back to the slides |
| 05:23 | The block numbers are circled as shown in the figure. |
| 05:27 | Now let me switch back to the 'blockMeshDict file'. |
| 05:31 | Leave some space. |
| 05:33 | Now enter the type of the block i.e. Hex, leave some space. |
| 05:41 | Now enter the points for the blocks. |
| 05:46 | Open, close brackets. |
| 05:48 | Leave some space, open close brackets, leave some space the simple Grading can be kept as (1 1 1) and press Enter. |
| 06:04 | For creating the blocks, please refer to the tutorial on creating simple geometry in OpenFOAM. |
| 06:11 | Note that there will be more number of blocks in this example. |
| 06:16 | Now, insert a close bracket. |
| 06:19 | Insert a semi-colon, and press Enter. Again press Enter. |
| 06:25 | In the next line, type "edges" and press Enter. |
| 06:31 | Insert a open bracket and press Enter. |
| 06:35 | Here you need to enter the points which are the end points of the arcs. |
| 06:40 | Leave some space and type "arc". Leave some space, type the points which are the end points of the arc. |
| 06:49 | Let me switch back to the slide. Now, insert the end points of the arc |
| 06:55 | In this figure, we start with arc 0 5. |
| 07:02 | Let me switch back to the 'blockMeshDict file'. |
| 07:06 | Enter 0 space 5. |
| 07:09 | Leave some space. Insert open, close bracket. |
| 07:12 | In the bracket, enter the co-ordinates of any intermediate point in between the two arc points. |
| 07:20 | Now, let me switch back again to slides. |
| 07:23 | In the figure, you can see that you have to pick up a point in between the two end points of the arc. |
| 07:32 | In this geometry, I have picked up right half of the circle. |
| 07:37 | Using simple geometric relations, you can find the co-ordinates of the intermediate points as shown in the semi-circle. |
| 07:47 | Similarly you can repeat the procedure for rest of the semi-circle geometry. |
| 07:54 | Now, let me switch back to the 'blockMeshDict file'. |
| 07:57 | Press Enter. |
| 07:59 | Note that there are more number of arcs in this example. |
| 08:04 | Insert a close bracket. |
| 08:07 | Insert a semi -colon, press Enter, again press Enter. |
| 08:11 | Now enter the boundary patches after arcs. |
| 08:15 | Refer to the tutorial on Simple geometry in OpenFOAM, for entering the boundary patches. |
| 08:21 | Enter "boundary", press Enter. |
| 08:24 | Insert open bracket press Enter. Insert close bracket semi-colon, press Enter. |
| 08:30 | Again press Enter. |
| 08:35 | Now, in the next line, type "mergePatchPairs". |
| 08:38 | Note that 'P' here is capital. |
| 08:40 | Press Enter. |
| 08:43 | Insert a open bracket, press Enter. |
| 08:46 | Since there are no patches to be merged, this can be kept empty. |
| 08:48 | Insert a close bracket. |
| 08:50 | Insert a semi colon and press Enter. |
| 08:54 | Let me switch back to the slides. |
| 08:57 | Similarly, enter the co-ordinate points for the points in the front face of unit thickness of the geometry as shown in the figure. |
| 09:06 | Now, open a Command terminal. |
| 09:09 | In the command terminal, type the path for your case. |
| 09:13 | I have already set the path for the tutorial case of flow over cylinder. |
| 09:17 | In the terminal, type "blockMesh" for meshing the geometry and press Enter. |
| 09:25 | Meshing is done. |
| 09:33 | Now, type "paraFoam" in the terminal and press Enter to view the geometry. |
| 09:39 | Let me drag this to the capture area. |
| 09:43 | Now on left-hand side of object inspector menu, click Apply. |
| 09:49 | Geometry will be created as seen in the paraview window. |
| 09:54 | Scroll down the Object inspector menu. |
| 09:57 | Check or uncheck the Mesh field box. |
| 10:02 | You can see different regions of the geometry. |
| 10:06 | You can also see the wire frame of the geometry. |
| 10:09 | On top of the active variable control menu, in the drop down menu, change from Surface to wireframe. |
| 10:18 | You can see the wireframe model of the geometry. |
| 10:24 | Close this. Let me switch back to the slides. |
| 10:29 | In this tutorial, we learnt:How to create a curved geometry. |
| 10:33 | How to enter points for edges in OpenFOAM. |
| 10:37 | This brings us to the end of the tutorial. |
| 10:41 | As an Assignment-Create a geometry with inner semi-circle of radius 2 meters and outer semi- circle of radius 4 meters and view the geometry in paraview. |
| 10:55 | Watch the video available at this URL: http://spoken-tutorial.org/What_is_a_Spoken_Tutorial |
| 10:58 | It summarizes the Spoken Tutorial project. |
| 11:01 | If you do not have good bandwidth, you can download and watch it. |
| 11:06 | The Spoken Tutorial project team: |
| 11:09 | Conducts workshops using spoken tutorials |
| 11:11 | Gives certificates to those who pass an online test. |
| 11:15 | For more details, please write to: contact@spoken-tutorial.com |
| 11:38 | Spoken Tutorials are part of Talk to a Teacher project. |
| 11:40 | It is supported by the National Mission on Education through ICT, MHRD, Government of India. |
| 11:45 | More information on this mission is available at this link: |
| 11:50 | This is Rahul Joshi from IIT Bombay, signing off. Thanks for joining |
