Difference between revisions of "OpenFOAM/C2/Creating-simple-geometry-in-OpenFOAM/English-timed"
From Script | Spoken-Tutorial
Sandhya.np14 (Talk | contribs) |
|||
(5 intermediate revisions by 3 users not shown) | |||
Line 14: | Line 14: | ||
|- | |- | ||
| 00:08 | | 00:08 | ||
− | | | + | | How to create simple geometry |
|- | |- | ||
| 00:11 | | 00:11 | ||
− | | | + | | How to view the geometry in '''paraview'''. |
|- | |- | ||
| 00:15 | | 00:15 | ||
− | | To record this tutorial, | + | | To record this tutorial,I am using: '''Linux Operating system Ubuntu''' version 10.04 '''OpenFOAM''' version 2.1.0 '''ParaView''' version 3.12.0 |
|- | |- | ||
− | | 00: | + | | 00:26 |
− | | | + | | 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: | + | | 00:30 |
− | | In '''CFD''' the | + | | In '''CFD''' the Pre-processing part consists of creating geometry and meshing it. |
|- | |- | ||
− | | 00: | + | | 00:37 |
| Let us take the '''Lid driven cavity''' case of the previous tutorial as an example. | | Let us take the '''Lid driven cavity''' case of the previous tutorial as an example. | ||
|- | |- | ||
− | | 00: | + | | 00:41 |
− | | Recall the '''path''' for the earlier tutorial | + | | Recall the '''path''' for the earlier tutorial. |
|- | |- | ||
− | | 00: | + | | 00:44 |
− | | I have already opened the '''command terminal''' and entered the '''path''' for '''lid driven cavity'''. | + | | I have already opened the '''command terminal''' and entered the '''path''' for '''lid driven cavity'''. |
|- | |- | ||
− | | | + | | 00:48 |
+ | | To source the OpenFOAM version 5, type:$of5. To go to the run folder, type:$cd $FOAM_RUN. To open the cavity case directory, type:$cd tutorials/incompressible/icoFoam/cavity/cavity. To list the contents of case directory, type:$ls. | ||
+ | |||
+ | |||
+ | |- | ||
+ | | 00:54 | ||
| There are three folders '0, constant' and 'system'. 'Geometry' is inside the 'polymesh' folder of 'constant'. | | There are three folders '0, constant' and 'system'. 'Geometry' is inside the 'polymesh' folder of 'constant'. | ||
|- | |- | ||
− | | | + | | 01:11 |
| In the command terminal, type: '''cd space constant''' and press '''Enter'''. | | In the command terminal, type: '''cd space constant''' and press '''Enter'''. | ||
|- | |- | ||
− | | 01: | + | | 01:19 |
| Now, type "ls" and press '''Enter'''. | | Now, type "ls" and press '''Enter'''. | ||
|- | |- | ||
− | | 01: | + | | 01:21 |
− | | In this, there is another folder called as ' | + | | In this, there is another folder called as 'polyMesh'. |
|- | |- | ||
− | | 01: | + | | 01:26 |
|Now type: '''cd space polymesh''' and press '''Enter'''. | |Now type: '''cd space polymesh''' and press '''Enter'''. | ||
|- | |- | ||
− | | 01: | + | | 01:34 |
|Now type "ls" and press '''Enter'''. | |Now type "ls" and press '''Enter'''. | ||
|- | |- | ||
− | | 01: | + | | 01:39 |
+ | |To list the contents of the cavity directory, type:$ls. 0 constant system. To open the system directory, type:$cd system. To list the contents of the system directory, type:$ls blockMeshDict controlDict fvSchemes fvSolution. | ||
+ | |||
+ | |- | ||
+ | | 01:45 | ||
| This contains the 'geometry' file called as 'blockMeshDict'. | | This contains the 'geometry' file called as 'blockMeshDict'. | ||
|- | |- | ||
− | | 01: | + | | 01:48 |
| Open the 'blockMeshDict' file with any '''editor''' of your choice. | | Open the 'blockMeshDict' file with any '''editor''' of your choice. | ||
|- | |- | ||
− | | 01: | + | | 01:52 |
| In the terminal, type: '''gedit space blockMeshDict'''( Note that M and D are capital) and press '''Enter'''. | | In the terminal, type: '''gedit space blockMeshDict'''( Note that M and D are capital) and press '''Enter'''. | ||
|- | |- | ||
− | | | + | | 02:07 |
|Let me drag this to the capture area. | |Let me drag this to the capture area. | ||
|- | |- | ||
− | | | + | | 02:11 |
|Now minimize this. | |Now minimize this. | ||
|- | |- | ||
− | | | + | | 02:15 |
− | | Let me switch back to the '''slide''' | + | | Let me switch back to the '''slide'''. |
|- | |- | ||
− | | | + | | 02:17 |
| In '''openfoam''', the entire '''geometry''' is broken into '''blocks '''. | | In '''openfoam''', the entire '''geometry''' is broken into '''blocks '''. | ||
|- | |- | ||
− | | | + | | 02:21 |
− | | The blocks are numbered starting from | + | | The blocks are numbered starting from 0 (zero) as shown in the figure. |
|- | |- | ||
− | | 02: | + | | 02:30 |
− | | Note that in | + | | Note that in OpenFOAM, for creating a 2D geometry you need to give an unit cell thickness value in the z-axis. |
|- | |- | ||
− | | 02: | + | | 02:41 |
| '''lid driven cavity''' is of length 1 and height 1. Minimize the slide. | | '''lid driven cavity''' is of length 1 and height 1. Minimize the slide. | ||
|- | |- | ||
− | | 02: | + | | 02:51 |
− | | On your desktop, create an empty file by right click > create document > Empty file. Name this as 'blockMeshDict | + | | On your desktop, create an empty file by right click > '''create document > Empty file'''. Name this as 'blockMeshDict'. (Note that M and D here are capital). |
|- | |- | ||
− | | | + | | 03:10 |
− | | Open this. Now | + | | Open this. Now, copy the data from the original '''lid driven cavity''' 'blockMeshDict' file to the new 'blockMeshDict' file from line 0. |
|- | |- | ||
− | | | + | | 03:21 |
| Scroll up line 0 upto 'convertTometers'. Copy this and '''paste''' it here. | | Scroll up line 0 upto 'convertTometers'. Copy this and '''paste''' it here. | ||
|- | |- | ||
− | | 03: | + | | 03:38 |
| Scroll down. Now leave some space after 'converttometers'. | | Scroll down. Now leave some space after 'converttometers'. | ||
|- | |- | ||
− | | 03: | + | | 03:44 |
| Enter 1 as the geometry is in meters. Insert a semicolon and press '''Enter'''. | | Enter 1 as the geometry is in meters. Insert a semicolon and press '''Enter'''. | ||
|- | |- | ||
− | | 03: | + | | 03:52 |
|Again press '''Enter'''. In the file, type "vertices" and press '''Enter'''. | |Again press '''Enter'''. In the file, type "vertices" and press '''Enter'''. | ||
|- | |- | ||
− | | | + | | 04:01 |
| Insert the open bracket and press '''Enter'''. | | Insert the open bracket and press '''Enter'''. | ||
|- | |- | ||
− | | | + | | 04:04 |
− | | Press the tab key. Start with point 0, insert open, close brackets, '''Enter'''. | + | | Press the '''tab''' key. Start with point 0, insert open, close brackets, '''Enter'''. |
|- | |- | ||
− | | | + | | 04:14 |
− | | '''0 space 0 space 0 '''and press '''Enter'''. Again, press tab key, open close bracket . | + | | '''0 space 0 space 0 '''and press '''Enter'''. Again, press '''tab''' key, open close bracket . |
|- | |- | ||
− | | 04: | + | | 04:24 |
− | | | + | | Move towards point 1 in positive x-axis and enter ''' 1 space 0 space 0''' and press '''Enter'''. |
|- | |- | ||
− | | 04: | + | | 04:34 |
− | |Again press tab key, open close bracket. Move towards point 2 in positive x-y plane and enter '''1 space 1 space 0''' and press '''Enter'''. | + | |Again press the tab key, open close bracket. Move towards point 2 in the positive x-y plane and enter '''1 space 1 space 0''' and press '''Enter'''. |
|- | |- | ||
− | | 04: | + | | 04:48 |
− | |Again press tab key, open close bracket. Enter the 3rd point in positive y-axis '''0 space 1 space 0 ''', press '''Enter'''. | + | |Again press '''tab''' key, open close bracket. Enter the 3rd point in positive y-axis '''0 space 1 space 0 ''', press '''Enter'''. |
|- | |- | ||
− | | | + | | 05:01 |
− | | Again press tab key. Enter the 4th point on the front face, open close bracket '''0 space 0 space 0.1''' and press '''Enter'''. | + | | Again press the '''tab''' key. Enter the 4th point on the front face, open close bracket, '''0 space 0 space 0.1''' and press '''Enter'''. |
|- | |- | ||
− | | | + | | 05:13 |
| Similarly, enter the other points with one unit value in the positive z- axis. | | Similarly, enter the other points with one unit value in the positive z- axis. | ||
|- | |- | ||
− | | | + | | 05:19 |
| close the bracket and insert a semicolon after it. Press '''Enter''', again press '''Enter'''. | | close the bracket and insert a semicolon after it. Press '''Enter''', again press '''Enter'''. | ||
|- | |- | ||
− | | 05: | + | | 05:26 |
− | | Below vertices are the blocks. Type blocks and press '''Enter'''. Insert a | + | | Below vertices are the blocks. Type blocks and press '''Enter'''. Insert a open bracket and press '''Enter'''. |
|- | |- | ||
− | | 05: | + | | 05:39 |
|Let me switch back to the slides. | |Let me switch back to the slides. | ||
|- | |- | ||
− | | 05: | + | | 05:41 |
| Note that '''Lid driven cavity''' is taken as a single block. | | Note that '''Lid driven cavity''' is taken as a single block. | ||
|- | |- | ||
− | | 05: | + | | 05:46 |
| Let me switch back to 'blockmeshdict'. | | Let me switch back to 'blockmeshdict'. | ||
|- | |- | ||
− | | 05: | + | | 05:48 |
− | |Enter the points for the | + | |Enter the points for the block in the clockwise sense. |
|- | |- | ||
− | | 05: | + | | 05:53 |
− | |We are using here '''hexa | + | |We are using here '''hexa hedral blocks '''for '''meshing.''' |
|- | |- | ||
− | | 05: | + | | 05:56 |
− | |Now, type "hex". Leave some space. In brackets, enter ''' 0 space | + | |Now, type "hex". Leave some space. In brackets, enter ''' 0 space 1 2 3 4 5 6 7 ''', again leave some space. |
|- | |- | ||
− | | | + | | 06:15 |
| Note that for multiple blocks, the points will be more. | | Note that for multiple blocks, the points will be more. | ||
|- | |- | ||
− | | | + | | 06:20 |
− | |After this, enter the grid points in the x, y and z directions. | + | |After this, enter the '''grid''' points in the x, y and z directions. |
|- | |- | ||
− | | 06: | + | | 06:25 |
|In brackets, open close brackets, enter '''30 space 30 space 1'''. Leave some space, you can modify the grid as and when needed. | |In brackets, open close brackets, enter '''30 space 30 space 1'''. Leave some space, you can modify the grid as and when needed. | ||
|- | |- | ||
− | | 06: | + | | 06:38 |
− | |Grid point in z-axis can be taken as one. | + | |Grid point in the z-axis can be taken as one. |
|- | |- | ||
− | | 06: | + | | 06:44 |
− | |Now, leave some space and type "simple | + | |Now, leave some space and type "simple Grading". Leave some space, open close bracket, enter '''1 space 1 space 1 '''. |
|- | |- | ||
− | | 06: | + | | 06:58 |
− | | This is the grid spacing in the x, y and z | + | | This is the grid spacing in the x, y and z directions. Press '''Enter'''. |
|- | |- | ||
− | | | + | | 07:05 |
| Insert close bracket, insert a semicolon and press '''Enter'''. | | Insert close bracket, insert a semicolon and press '''Enter'''. | ||
|- | |- | ||
− | | | + | | 07:11 |
| Again press '''Enter'''. Now type "edges" and press '''Enter'''. | | Again press '''Enter'''. Now type "edges" and press '''Enter'''. | ||
|- | |- | ||
− | | | + | | 07:17 |
− | | As this is a simple geometry | + | | As this is a simple geometry, '''edges''' can be kept empty. |
|- | |- | ||
− | | 07: | + | | 07:21 |
− | | Insert open bracket, press '''Enter''', close the bracket | + | | Insert open bracket, press '''Enter''', close the bracket. Insert a semicolon and press '''Enter'''. |
|- | |- | ||
− | | 07: | + | | 07:28 |
| Again press '''Enter'''. Below '''edges''' are the '''boundary conditions'''. | | Again press '''Enter'''. Below '''edges''' are the '''boundary conditions'''. | ||
|- | |- | ||
− | | 07: | + | | 07:33 |
− | | Here you need to enter the '''boundary | + | | Here you need to enter the '''boundary names''' for the '''faces'''. |
|- | |- | ||
− | | 07: | + | | 07:37 |
|Type "boundary" and press '''Enter''' . | |Type "boundary" and press '''Enter''' . | ||
|- | |- | ||
− | | 07: | + | | 07:41 |
|Insert an open bracket and press '''Enter'''. | |Insert an open bracket and press '''Enter'''. | ||
|- | |- | ||
− | | 07: | + | | 07:45 |
− | |Now let me switch back to the slides. | + | |Now, let me switch back to the slides. |
|- | |- | ||
− | |07: | + | |07:48 |
|In the geometry, the upper wall is moving and other three walls are fixed. | |In the geometry, the upper wall is moving and other three walls are fixed. | ||
|- | |- | ||
− | | 07: | + | | 07:53 |
| The front and back faces are named as 'empty' as this is a 2D problem. | | The front and back faces are named as 'empty' as this is a 2D problem. | ||
|- | |- | ||
− | | | + | | 08:01 |
| Open the new 'blockMeshDict' file again. | | Open the new 'blockMeshDict' file again. | ||
|- | |- | ||
− | | | + | |08:04 |
| In '''boundary''', put the name of the '''patch''' as 'moving wall' . Press '''Enter'''. | | In '''boundary''', put the name of the '''patch''' as 'moving wall' . Press '''Enter'''. | ||
|- | |- | ||
− | | | + | | 08:16 |
| Now, insert a open curly bracket and press '''Enter'''. | | Now, insert a open curly bracket and press '''Enter'''. | ||
|- | |- | ||
− | | | + | | 08:20 |
− | | Now enter the '''type''' for the '''moving wall''' , enter | + | | Now, enter the '''type''' for the '''moving wall''' , enter "type" space "wall". |
|- | |- | ||
− | | 08: | + | | 08:28 |
| Insert a semicolon and press '''Enter'''. | | Insert a semicolon and press '''Enter'''. | ||
+ | |||
|- | |- | ||
− | | 08: | + | | 08:33 |
− | |Now insert open bracket and press '''Enter'''. Press the tab key, open close bracket. | + | |Now, faces, now press Enter, insert open bracket and press '''Enter'''. Press the '''tab''' key, open close bracket. |
+ | |||
|- | |- | ||
− | | 08: | + | | 08:47 |
− | |In this bracket, enter the | + | |In this bracket, enter the points for faces. |
+ | |||
|- | |- | ||
− | | 08: | + | | 08:51 |
− | |Let me switch to the slide. | + | |Let me switch back to the slide. |
|- | |- | ||
− | | 08: | + | | 08:54 |
− | | Note that order of the points should be in such a way that the | + | | Note that the order of the points should be in such a way that the thumb should be normal to the face |
|- | |- | ||
− | | | + | | 09:01 |
− | | | + | | and fingers making a curl as shown in the figure. |
|- | |- | ||
− | | | + | | 09:06 |
|The curl can be clockwise or anti-clockwise. | |The curl can be clockwise or anti-clockwise. | ||
+ | |||
|- | |- | ||
− | | | + | | 09:09 |
− | | Also | + | | Also note that the points should match with the points inserted in vertices. |
|- | |- | ||
− | | | + | | 09:14 |
− | |Now, let me switch back to the new ' | + | |Now, let me switch back to the new 'blockMeshDict' file. |
|- | |- | ||
− | | | + | | 09:18 |
|Now in the faces, enter '''3 space 7 space 6 space 2'''. | |Now in the faces, enter '''3 space 7 space 6 space 2'''. | ||
+ | |||
|- | |- | ||
− | | 09: | + | | 09:28 |
| Let me switch back to the slide. These are the points for the moving wall 3, 7, 6, 2. | | Let me switch back to the slide. These are the points for the moving wall 3, 7, 6, 2. | ||
|- | |- | ||
− | | 09: | + | | 09:35 |
|Minimize this. Note that you can start from any point on that face. Now press '''Enter'''. | |Minimize this. Note that you can start from any point on that face. Now press '''Enter'''. | ||
+ | |||
|- | |- | ||
− | | 09: | + | | 09:44 |
− | |Close the bracket | + | |Close the bracket. Again press '''Enter'''. Close the curly bracket. |
+ | |||
|- | |- | ||
− | | 09: | + | | 09:55 |
− | |Another note | + | |Another note: we need to enter a semi colon after you insert the points for faces. Now after the curly brackets, press '''Enter''', again press '''Enter'''. |
|- | |- | ||
− | | | + | | 10:01 |
− | |Now, similarly enter '''boundary condition''' and '''faces''' for the '''fixed | + | |Now, similarly enter '''boundary condition''' and '''faces''' for the '''fixed walls'''. |
|- | |- | ||
− | | | + | | 10:06 |
− | | Being a 2D problem the type of boundary for front and back faces can be kept as empty. | + | | Being a 2D problem the type of boundary for the front and back faces can be kept as empty. |
+ | |||
|- | |- | ||
− | | | + | | 10:13 |
|Refer to the figure in the slide. For entering the points, minimize this. | |Refer to the figure in the slide. For entering the points, minimize this. | ||
|- | |- | ||
− | | | + | | 10:19 |
| Insert the closed brackets, put a semicolon and press '''Enter''', again press '''Enter'''. | | Insert the closed brackets, put a semicolon and press '''Enter''', again press '''Enter'''. | ||
|- | |- | ||
− | | | + | | 10:26 |
|Now type "mergePatchPairs" and press '''Enter'''. | |Now type "mergePatchPairs" and press '''Enter'''. | ||
|- | |- | ||
− | | 10: | + | | 10:32 |
− | | Since there are no patches to | + | | Since there are no patches to be merged, it can be kept empty. |
+ | |||
|- | |- | ||
− | | 10: | + | | 10:35 |
− | | Insert open close | + | | Insert open close brackets. Insert a semicolon and press '''Enter'''. |
+ | |||
|- | |- | ||
− | | 10: | + | | 10:41 |
− | | We are done with creating the ' | + | | We are done with creating the 'blockMeshDict' file. '''Save''' this. |
+ | |||
|- | |- | ||
− | | 10: | + | | 10:46 |
| The complete 'blockMeshDict' file is as shown here. | | The complete 'blockMeshDict' file is as shown here. | ||
|- | |- | ||
− | |10: | + | |10:54 |
| Close both the 'blockMeshDict' files. | | Close both the 'blockMeshDict' files. | ||
|- | |- | ||
− | | 10: | + | | 10:56 |
− | | Note that the '''command terminal''' will not work until '''blockMeshDict''' file is closed. | + | | Note that the '''command terminal''' will not work until the '''blockMeshDict''' file is closed. |
|- | |- | ||
− | | | + | | 11:01 |
− | | Switch back to the terminal. Now, type '''cd (dot) (dot)''' twice to return back to the 'cavity' folder. Now '''Mesh the geometry'''. | + | | Switch back to the terminal. Now, type '''cd space (dot) (dot)''' twice to return back to the 'cavity' folder. Now '''Mesh the geometry'''. |
|- | |- | ||
− | | | + | |11:12 |
− | |To do this, on the | + | |To do this, on the terminal, type: "blockMesh" and press '''Enter'''. |
|- | |- | ||
− | | | + | | 11:20 |
− | |Now, view the '''geometry''' by typing | + | |Now, view the '''geometry''' by typing on the '''command terminal''' '''paraFoam''' and press '''Enter'''. |
|- | |- | ||
− | | | + | | 11:27 |
| This will open the ''' ParaView''' window. | | This will open the ''' ParaView''' window. | ||
|- | |- | ||
− | | 11: | + | | 11:30 |
− | | Now, on the left hand side, click '''Apply''' on '''object inspector | + | | Now, on the left hand side, click '''Apply''' on '''object inspector''' menu. Thus, you can see the geometry. |
|- | |- | ||
− | | 11: | + | | 11:39 |
− | | Now let me switch back to the slides. | + | | Now, let me switch back to the slides. |
|- | |- | ||
− | | 11: | + | | 11:43 |
− | | | + | | In this tutorial, we learnt: |
|- | |- | ||
− | | 11: | + | | 11:45 |
− | | | + | | Creating a simple geometry in '''OpenFOAM''' |
|- | |- | ||
− | | 11: | + | | 11:49 |
− | | | + | | Viewing the geometry in '''Paraview '''. |
|- | |- | ||
− | | 11: | + | | 11:52 |
| This brings us to the end of the tutorial. | | This brings us to the end of the tutorial. | ||
|- | |- | ||
− | | 11: | + | | 11:56 |
| As an Assignment- | | As an Assignment- | ||
|- | |- | ||
− | | 11: | + | | 11:58 |
− | | Change the | + | | Change the dimensions of the '''lid driven cavity''', change the grid size to '''50 50 1''' and view the geometry in '''paraView'''. |
|- | |- | ||
− | | | + | | 12:08 |
| Watch the video available at this URL: [http://spoken-tutorial.org/What_is_a_Spoken_Tutorial] | | Watch the video available at this URL: [http://spoken-tutorial.org/What_is_a_Spoken_Tutorial] | ||
|- | |- | ||
− | | | + | | 12:11 |
| It summarizes the Spoken Tutorial project. | | It summarizes the Spoken Tutorial project. | ||
|- | |- | ||
− | | | + | | 12:13 |
− | | If you do not have good bandwidth, you can download and watch it. | + | | If you do not have a good bandwidth, you can download and watch it. |
|- | |- | ||
− | | | + | | 12:18 |
| The Spoken Tutorial project team: | | The Spoken Tutorial project team: | ||
|- | |- | ||
− | | | + | | 12:20 |
− | | | + | | Conducts workshops using spoken tutorials |
|- | |- | ||
− | | | + | | 12:22 |
− | | | + | | Gives certificates to those who pass an online test. |
|- | |- | ||
− | | | + | | 12:25 |
| For more details, please write to: | | For more details, please write to: | ||
'''contact@spoken-tutorial.org''' | '''contact@spoken-tutorial.org''' | ||
|- | |- | ||
− | | 12: | + | | 12:48 |
− | | '''Spoken Tutorial''' project is part of '''Talk to a Teacher''' project. | + | | '''Spoken Tutorial''' project is part of the '''Talk to a Teacher''' project. |
|- | |- | ||
− | | 12: | + | | 12:51 |
| It is supported by the National Mission on Education through ICT, MHRD, Government of India. | | It is supported by the National Mission on Education through ICT, MHRD, Government of India. | ||
|- | |- | ||
− | | 12: | + | | 12:57 |
− | | More information on | + | | More information on this mission is available at the following URL: |
[http://spoken-tutorial.org/NMEICT-Intro] | [http://spoken-tutorial.org/NMEICT-Intro] | ||
|- | |- | ||
− | | | + | | 13:02 |
| | This is Rahul Joshi from '''IIT Bombay''', signing off. Thanks for joining. | | | This is Rahul Joshi from '''IIT Bombay''', signing off. Thanks for joining. | ||
|} | |} |
Latest revision as of 03:39, 13 March 2019
Time | Narration |
00:01 | Hello and welcome to the spoken tutorial on creating simple geometry in OpenFOAM. |
00:06 | In this tutorial, I will show you: |
00:08 | How to create simple geometry |
00:11 | How to view the geometry in paraview. |
00:15 | To record this tutorial,I am using: Linux Operating system Ubuntu version 10.04 OpenFOAM version 2.1.0 ParaView version 3.12.0 |
00:26 | 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. |
00:30 | In CFD the Pre-processing part consists of creating geometry and meshing it. |
00:37 | Let us take the Lid driven cavity case of the previous tutorial as an example. |
00:41 | Recall the path for the earlier tutorial. |
00:44 | I have already opened the command terminal and entered the path for lid driven cavity. |
00:48 | To source the OpenFOAM version 5, type:$of5. To go to the run folder, type:$cd $FOAM_RUN. To open the cavity case directory, type:$cd tutorials/incompressible/icoFoam/cavity/cavity. To list the contents of case directory, type:$ls.
|
00:54 | There are three folders '0, constant' and 'system'. 'Geometry' is inside the 'polymesh' folder of 'constant'. |
01:11 | In the command terminal, type: cd space constant and press Enter. |
01:19 | Now, type "ls" and press Enter. |
01:21 | In this, there is another folder called as 'polyMesh'. |
01:26 | Now type: cd space polymesh and press Enter. |
01:34 | Now type "ls" and press Enter. |
01:39 | To list the contents of the cavity directory, type:$ls. 0 constant system. To open the system directory, type:$cd system. To list the contents of the system directory, type:$ls blockMeshDict controlDict fvSchemes fvSolution. |
01:45 | This contains the 'geometry' file called as 'blockMeshDict'. |
01:48 | Open the 'blockMeshDict' file with any editor of your choice. |
01:52 | In the terminal, type: gedit space blockMeshDict( Note that M and D are capital) and press Enter. |
02:07 | Let me drag this to the capture area. |
02:11 | Now minimize this. |
02:15 | Let me switch back to the slide. |
02:17 | In openfoam, the entire geometry is broken into blocks . |
02:21 | The blocks are numbered starting from 0 (zero) as shown in the figure. |
02:30 | Note that in OpenFOAM, for creating a 2D geometry you need to give an unit cell thickness value in the z-axis. |
02:41 | lid driven cavity is of length 1 and height 1. Minimize the slide. |
02:51 | On your desktop, create an empty file by right click > create document > Empty file. Name this as 'blockMeshDict'. (Note that M and D here are capital). |
03:10 | Open this. Now, copy the data from the original lid driven cavity 'blockMeshDict' file to the new 'blockMeshDict' file from line 0. |
03:21 | Scroll up line 0 upto 'convertTometers'. Copy this and paste it here. |
03:38 | Scroll down. Now leave some space after 'converttometers'. |
03:44 | Enter 1 as the geometry is in meters. Insert a semicolon and press Enter. |
03:52 | Again press Enter. In the file, type "vertices" and press Enter. |
04:01 | Insert the open bracket and press Enter. |
04:04 | Press the tab key. Start with point 0, insert open, close brackets, Enter. |
04:14 | 0 space 0 space 0 and press Enter. Again, press tab key, open close bracket . |
04:24 | Move towards point 1 in positive x-axis and enter 1 space 0 space 0 and press Enter. |
04:34 | Again press the tab key, open close bracket. Move towards point 2 in the positive x-y plane and enter 1 space 1 space 0 and press Enter. |
04:48 | Again press tab key, open close bracket. Enter the 3rd point in positive y-axis 0 space 1 space 0 , press Enter. |
05:01 | Again press the tab key. Enter the 4th point on the front face, open close bracket, 0 space 0 space 0.1 and press Enter. |
05:13 | Similarly, enter the other points with one unit value in the positive z- axis. |
05:19 | close the bracket and insert a semicolon after it. Press Enter, again press Enter. |
05:26 | Below vertices are the blocks. Type blocks and press Enter. Insert a open bracket and press Enter. |
05:39 | Let me switch back to the slides. |
05:41 | Note that Lid driven cavity is taken as a single block. |
05:46 | Let me switch back to 'blockmeshdict'. |
05:48 | Enter the points for the block in the clockwise sense. |
05:53 | We are using here hexa hedral blocks for meshing. |
05:56 | Now, type "hex". Leave some space. In brackets, enter 0 space 1 2 3 4 5 6 7 , again leave some space. |
06:15 | Note that for multiple blocks, the points will be more. |
06:20 | After this, enter the grid points in the x, y and z directions. |
06:25 | In brackets, open close brackets, enter 30 space 30 space 1. Leave some space, you can modify the grid as and when needed. |
06:38 | Grid point in the z-axis can be taken as one. |
06:44 | Now, leave some space and type "simple Grading". Leave some space, open close bracket, enter 1 space 1 space 1 . |
06:58 | This is the grid spacing in the x, y and z directions. Press Enter. |
07:05 | Insert close bracket, insert a semicolon and press Enter. |
07:11 | Again press Enter. Now type "edges" and press Enter. |
07:17 | As this is a simple geometry, edges can be kept empty. |
07:21 | Insert open bracket, press Enter, close the bracket. Insert a semicolon and press Enter. |
07:28 | Again press Enter. Below edges are the boundary conditions. |
07:33 | Here you need to enter the boundary names for the faces. |
07:37 | Type "boundary" and press Enter . |
07:41 | Insert an open bracket and press Enter. |
07:45 | Now, let me switch back to the slides. |
07:48 | In the geometry, the upper wall is moving and other three walls are fixed. |
07:53 | The front and back faces are named as 'empty' as this is a 2D problem. |
08:01 | Open the new 'blockMeshDict' file again. |
08:04 | In boundary, put the name of the patch as 'moving wall' . Press Enter. |
08:16 | Now, insert a open curly bracket and press Enter. |
08:20 | Now, enter the type for the moving wall , enter "type" space "wall". |
08:28 | Insert a semicolon and press Enter. |
08:33 | Now, faces, now press Enter, insert open bracket and press Enter. Press the tab key, open close bracket. |
08:47 | In this bracket, enter the points for faces. |
08:51 | Let me switch back to the slide. |
08:54 | Note that the order of the points should be in such a way that the thumb should be normal to the face |
09:01 | and fingers making a curl as shown in the figure. |
09:06 | The curl can be clockwise or anti-clockwise. |
09:09 | Also note that the points should match with the points inserted in vertices. |
09:14 | Now, let me switch back to the new 'blockMeshDict' file. |
09:18 | Now in the faces, enter 3 space 7 space 6 space 2. |
09:28 | Let me switch back to the slide. These are the points for the moving wall 3, 7, 6, 2. |
09:35 | Minimize this. Note that you can start from any point on that face. Now press Enter. |
09:44 | Close the bracket. Again press Enter. Close the curly bracket. |
09:55 | Another note: we need to enter a semi colon after you insert the points for faces. Now after the curly brackets, press Enter, again press Enter. |
10:01 | Now, similarly enter boundary condition and faces for the fixed walls. |
10:06 | Being a 2D problem the type of boundary for the front and back faces can be kept as empty. |
10:13 | Refer to the figure in the slide. For entering the points, minimize this. |
10:19 | Insert the closed brackets, put a semicolon and press Enter, again press Enter. |
10:26 | Now type "mergePatchPairs" and press Enter. |
10:32 | Since there are no patches to be merged, it can be kept empty. |
10:35 | Insert open close brackets. Insert a semicolon and press Enter. |
10:41 | We are done with creating the 'blockMeshDict' file. Save this. |
10:46 | The complete 'blockMeshDict' file is as shown here. |
10:54 | Close both the 'blockMeshDict' files. |
10:56 | Note that the command terminal will not work until the blockMeshDict file is closed. |
11:01 | Switch back to the terminal. Now, type cd space (dot) (dot) twice to return back to the 'cavity' folder. Now Mesh the geometry. |
11:12 | To do this, on the terminal, type: "blockMesh" and press Enter. |
11:20 | Now, view the geometry by typing on the command terminal paraFoam and press Enter. |
11:27 | This will open the ParaView window. |
11:30 | Now, on the left hand side, click Apply on object inspector menu. Thus, you can see the geometry. |
11:39 | Now, let me switch back to the slides. |
11:43 | In this tutorial, we learnt: |
11:45 | Creating a simple geometry in OpenFOAM |
11:49 | Viewing the geometry in Paraview . |
11:52 | This brings us to the end of the tutorial. |
11:56 | As an Assignment- |
11:58 | Change the dimensions of the lid driven cavity, change the grid size to 50 50 1 and view the geometry in paraView. |
12:08 | Watch the video available at this URL: [1] |
12:11 | It summarizes the Spoken Tutorial project. |
12:13 | If you do not have a good bandwidth, you can download and watch it. |
12:18 | The Spoken Tutorial project team: |
12:20 | Conducts workshops using spoken tutorials |
12:22 | Gives certificates to those who pass an online test. |
12:25 | For more details, please write to:
contact@spoken-tutorial.org |
12:48 | Spoken Tutorial project is part of the Talk to a Teacher project. |
12:51 | It is supported by the National Mission on Education through ICT, MHRD, Government of India. |
12:57 | More information on this mission is available at the following URL: |
13:02 | This is Rahul Joshi from IIT Bombay, signing off. Thanks for joining. |
Contributors and Content Editors
DeepaVedartham, Gaurav, PoojaMoolya, Pratik kamble, Sandhya.np14, Sneha