Difference between revisions of "OpenFOAM/C2/Simulating-flow-in-a-Lid-Driven-Cavity/English-timed"

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|-
 
|-
 
|  09:08
 
|  09:08
| Now let me switch back to the slides
+
| Now let me switch back to the slides.
  
 
|-
 
|-
 
|  09:10
 
|  09:10
| Results obtained will be similar to this figure
+
| Results obtained will be similar to this figure.
  
 
|-
 
|-
 
| 09:16
 
| 09:16
| '''Validate''' the result on a  paper published on '''Lid Driven Cavity by : Ghia et al. (1982''') and  
+
| '''Validate''' the results on a  paper published on '''Lid Driven Cavity by : Ghia et al. (1982''') and  
Results '''obtained from Fluent'''
+
Results obtained from Fluent.
  
 
|-
 
|-
 
|09:24   
 
|09:24   
|  In this tutorial we learnt   
+
|  In this tutorial, we learnt:    
  
 
|-
 
|-
 
|  09:26
 
|  09:26
|File structure of '''Lid Driven cavity'''
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|* File structure of '''Lid Driven cavity'''
  
 
|-
 
|-
 
|  09:28
 
|  09:28
|'''Solved lid driven cavity'''.
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|* '''Solved lid driven cavity'''.
  
 
|-
 
|-
 
|  09:30
 
|  09:30
|'''Post-processing of solutions'''
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|* '''Post-processing of solutions'''
  
 
|-
 
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|  09:32
 
|  09:32
|And '''Validation'''
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|And '''Validation'''.
  
 
|-
 
|-
 
| 09:34
 
| 09:34
|  As as Assignment,  
+
|  As an assignment,  
  
 
|-
 
|-
 
|  09:35
 
|  09:35
|Change some '''parameters''' in the '''lid driven cavity'''
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|Change some parameters in the '''lid driven cavity'''.
  
 
|-
 
|-
 
|  09:38
 
|  09:38
|* '''Velocity Magnitude''' in the '''0 folder'''
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|* '''Velocity Magnitude''' in the '''0 folder'''.
 
|-
 
|-
 
|  09:41
 
|  09:41
|* '''Kinematic viscosity'''  in '''transportPorpoerties''' in constant folder
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|* '''Kinematic viscosity'''  in '''transport Properties''' in '''constant''' folder.
  
 
|-
 
|-
 
|  09:45
 
|  09:45
|And Plot results of '''u/U and y/L'''
+
|And, plot results of '''u/U and y/L'''.
  
 
|-
 
|-
 
| 09:50
 
| 09:50
| 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  
  
 
|-
 
|-
 
|  09:54
 
|  09:54
|It summarizes the Spoken Tutorial project.  
+
|It summarizes the '''Spoken Tutorial''' project.  
  
 
|-
 
|-
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|-
 
|-
 
|  10:00
 
|  10:00
|  The Spoken Tutorial Project Team
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|  The Spoken Tutorial project team:
  
 
|-
 
|-
 
|  10:02
 
|  10:02
|Conducts workshops using spoken tutorials
+
|* Conducts workshops using spoken tutorials
  
 
|-
 
|-
 
|  10:05
 
|  10:05
|Gives certificates to those who pass an online test
+
|* Gives certificates to those who pass an online test.
  
 
|-
 
|-
 
|  10:09
 
|  10:09
|For more details, please write to us at contact @spoken-tutorial.org
+
|For more details, please write to us at:
 +
contact@spoken-tutorial.org
  
 
|-
 
|-
 
| 10:15
 
| 10:15
| Spoken Tutorials are part of Talk to a Teacher project,
+
| '''Spoken Tutorials''' are part of '''Talk to a Teacher''' project.
  
 
|-
 
|-
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|-
 
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|  10:23
 
|  10:23
|More information on the same is available at the following URL link http://spoken-tutorial.org/NMEICT-Intro
+
|More information on the same is available at the following URLhttp://spoken-tutorial.org/NMEICT-Intro
  
 
|-
 
|-
 
| 10:27
 
| 10:27
|  This is Rahul Joshi from IIT BOMBAY signing off.
+
|  This is Rahul Joshi from IIT Bombay, signing off.
  
 
|-
 
|-
 
|  10:30
 
|  10:30
|Thanks for joining
+
|Thanks for joining.
  
 
|}
 
|}

Revision as of 14:42, 24 June 2016

Time Narration
00:01 Hello and welcome to the spoken tutorial on Simulating Flow in a Lid Driven Cavity using openFoam.
00:07 In this tutorial, I will show you:
00:09 * The Lid Driven Cavity file structure
00:12 * Meshing the Geometry
00:14 * Solving and post-processing results in Paraview
00:17 * Plotting & validating results on a spreadsheet.
00:21 To record this tutorial,
00:22 I am using: Linux Operating system Ubuntu version 10.04
00:27 OpenFOAM version 2.1.0 and ParaView version 3.12.0.
00:32 Lid driven cavity is the most widely used 2D test
00:36 case for validation of a CFD code.
00:39 This is the diagram of Lid Driven Cavity,
00:41 the boundary conditions remain the same.
00:44 A moving wall and three fixedwalls.
00:46 We are solving this for Reynolds no (Re) = 100.
00:50 The moving wall has a velocity of 1 meter per second.
00:54 The path for the Lid Driven Cavity is the same as discussed in the installation tutorial.
01:00 Now, open a command terminal.
01:02 To do this, press Ctrl+Alt+t keys simultaneously on your keyboard.
01:08 In the command terminal, type the path for the lid driven cavity
01:12 and type "run" and press Enter.
01:15 cd (space) tutorials and press Enter.
01:20 cd (space) incompressible and press Enter.
01:26 cd (space) icoFoam (Note that F here is capital) and press Enter.
01:33 cd (space) cavity and press Enter.
01:38 Now, type "ls" and press Enter.
01:41 In the file structure of cavity, you will see 3 folders : 0 , constant , and system.
01:46 Now, type cd (space) constant and press Enter.
01:52 Now type "ls" and press Enter.
01:55 The constant folder contains another folder named polyMesh and a file describing the physical properties of fluid.
02:01 Now, type cd (space) polymesh and Press Enter.
02:08 PolyMesh contains a file named 'blockMeshDict'.
02:12 Now type "ls" and press Enter.
02:15 You can see the blockMeshDict
02:17 To open up the blockMeshDict file, type gedit space blockMeshDict.

(Note that M and D here are capital)

Now press Enter.

02:30 This will Open up the blockMeshDict file.
02:32 Let me drag this to the capture area.
02:36 This contains: coordinates for the lid driven cavity,
02:41 blocking and meshing parameters
02:44 and boundary patches.
02:47 Since there are no arcs as well as no patches to be merged, edges and mergePatchPairs can be kept empty.
02:56 Now close this.
02:58 In the command terminal, type : cd (space) .. (dot) (dot) and press Enter.
03:04 Do this twice. You will come back to the cavity folder.
03:09 Now, type cd (space) system and press Enter.
03:15 Now type "ls", press Enter. This contains three files-
03:22 controlDict, fvSchemes and fvSolutions.
03:26 controlDict contains control parameters for start/end time.


03:30 fvSolution contains discritization schemes used in run time.
03:35 And, fvSchemes contains equation for solvers, tolerance etc.
03:40 Now, again type cd (space) (dot dot) .. and press Enter.
03:46 Now type cd ( space ) 0 (zero) and Press Enter.
03:53 Now type "ls" and press Enter.
03:57 This contains the initial values for boundary conditions like Pressure, Velocity, Temperature etc.
04:03 Now type cd ( space ) (dot dot) . . to return back to the cavity folder.
04:09 Now we need to mesh the geometry.
04:11 We are using a coarse mesh here.
04:14 Mesh the geometry by typing blockMesh in the terminal.
04:18 Now type blockMesh (Note that M here is capital) and press Enter.
04:25 The Meshing is done.
04:27 If there are some errors in the blockMesh file, it will be shown in the terminal.
04:31 To view the geometry,
04:32 type paraFoam. Note that 'F' here is capital and press Enter.
04:40 This will open the paraview window.
04:44 Now on the left hand side of the object inspector menu, click on Apply.
04:49 You can see the lid driven cavity geometry. Now close this.
04:58 Check the mesh by typing "checkMesh" in the terminal.
05:04 Note that 'M' here is capital and press Enter.
05:08 you can see the number of cells, skewness and other parameters which are associated with the mesh.
05:15 Let me switch back to the slides.
05:17 The solver we are using here is icoFoam:
05:20 icoFoam is a Transient solver for incompressible flow of newtonian fluids.
05:26 Let me switch back to the terminal.
05:29 In the terminal, type "icoFoam".
05:33 Note that 'F' here is capital and press Enter.
05:37 The Iterations running will be seen in the terminal window.
05:40 After the solving is done, type paraFoam in the terminal to view the geometry and the results.
05:54 On the left hand side of object inspector menu
05:57 click on Apply.
05:58 Now Scroll down the properties on object inspector menu.
06:02 you can see mesh parts, Volume Fields etc.
06:07 Check or uncheck these boxes in the mesh part, to view the different boundary regions of Lid driven cavity.
06:15 Now, after this, on top of the left-hand side on active variable control drop-down menu, change this from solid color to p or capital U which are the initial conditions such as pressure, velocity.
06:31 I will select capital 'U'. Now this will show you the initial condition of velocity.
06:37 On top of the paraview window, you will see the VCR control.
06:44 Click on the play button.
06:47 Now this is the final result of velocity for the lid driven cavity.
06:52 Toggle on the color legend by clicking on the top left of the active variable control menu.
07:03 This is the color legend for U velocity.
07:07 We need to validate the results obtained.


07:09 To do this, let us plot the U and V velocity.
07:12 To do this, go to Filters scroll down > Data Analysis > Plot Over line.
07:21 Click on it.
07:23 You can see X , Y and Z axes.
07:25 Select the X & Y axis turn by turn.
07:31 I will select the X axis and click Apply.
07:37 You can see Pressure and velocity plots being plotted.
07:42 Since it is a non dimensional analysis, we need to plot the graph for u/U v/s y/L for Reynolds number =100
07:52 To do this, in Plot Data click on the Y-axis
07:58 and click APPLY.
08:01 You can see the plot.
08:03 Now in menu bar, go to File > Save Data.
08:09 Give appropriate name to your file.
08:11 I will give this as "cavity".
08:15 The file will be saved as ".csv" (dot csv) file.
08:19 Now click OK. Again click OK.
08:23 Now go to the cavity folder of openfoam directory.
08:29 Scroll down. you can see the cavity.csv file.
08:34 Open it in Open office or LibreOffice Spreadsheet.
08:39 In the LibreOffice spreadsheet, copy the U0 (u velocity) and to the right points 1(Y-axis) columns

in another spreadsheet.

08:48 Now, divide both these columns, that is, u zero by capital U and points 1 by capital L
08:59 and plot the results in libreoffice charts option on top, in the menu bar.
09:08 Now let me switch back to the slides.
09:10 Results obtained will be similar to this figure.
09:16 Validate the results on a paper published on Lid Driven Cavity by : Ghia et al. (1982) and

Results obtained from Fluent.

09:24 In this tutorial, we learnt:
09:26 * File structure of Lid Driven cavity
09:28 * Solved lid driven cavity.
09:30 * Post-processing of solutions
09:32 And Validation.
09:34 As an assignment,
09:35 Change some parameters in the lid driven cavity.
09:38 * Velocity Magnitude in the 0 folder.
09:41 * Kinematic viscosity in transport Properties in constant folder.
09:45 And, plot results of u/U and y/L.
09:50 Watch the video available at this URL:

http://spoken-tutorial.org/What_is_a_Spoken_Tutorial

09:54 It summarizes the Spoken Tutorial project.
09:57 If you do not have good bandwidth, you can download and watch it.
10:00 The Spoken Tutorial project team:
10:02 * Conducts workshops using spoken tutorials
10:05 * Gives certificates to those who pass an online test.
10:09 For more details, please write to us at:

contact@spoken-tutorial.org

10:15 Spoken Tutorials are part of Talk to a Teacher project.
10:18 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
10:23 More information on the same is available at the following URL: http://spoken-tutorial.org/NMEICT-Intro
10:27 This is Rahul Joshi from IIT Bombay, signing off.
10:30 Thanks for joining.

Contributors and Content Editors

DeepaVedartham, Gaurav, Nancyvarkey, PoojaMoolya, Sandhya.np14, Sneha