OpenFOAM/C3/Introduction-to-SnappyHexMesh/English-timed - Revision history

PoojaMoolya at 10:17, 10 March 2017

2017-03-10T10:17:04Z

PoojaMoolya at 13:05, 20 February 2017

2017-02-20T13:05:11Z

Sandhya.np14 at 12:06, 4 July 2016

2016-07-04T12:06:40Z

Sandhya.np14 at 11:45, 4 July 2016

2016-07-04T11:45:56Z

Sandhya.np14 at 11:35, 4 July 2016

2016-07-04T11:35:14Z

Pratik kamble: Created page with "{| border=1 | '''Time''' | '''Narration''' |- | 00:00 | Hello and welcome to the spoken tutorial on Introduction to '''snappyHexMesh''' in '''OpenFOAM'''. |- | 00:07 | In th..."

2015-12-01T09:41:41Z

Created page with "{| border=1 | '''Time''' | '''Narration''' |- | 00:00 | Hello and welcome to the spoken tutorial on Introduction to '''snappyHexMesh''' in '''OpenFOAM'''. |- | 00:07 | In th..."

New page

{| border=1
| '''Time'''
| '''Narration'''

|-
| 00:00
| Hello and welcome to the spoken tutorial on Introduction to '''snappyHexMesh''' in '''OpenFOAM'''.

|-
| 00:07
| In this tutorial, we will learn about
The parameters in '''snappyHexMesh'''
To generate '''Mesh''' in '''OpenFOAM'''.

|-
|00:14
| As a pre-requisite, the user requires
* Surface data files in '''STL''' format, located in '''constant/trisurface''' sub-directory of the '''case''' directory
* A domain with '''hex mesh'''
* '''snappyHexMeshDict''' dictionary located in the '''system''' sub-directory of''' case'''

|-
| 00:35
| To record this tutorial, I am using
* '''Ubuntu Linux''' operating system 12.04
* '''OpenFOAM''' version 2.2.2
* '''ParaView''' version 3.12.0

|-
| 00:50
| Let us learn to create a Mesh with the '''snappyHexMesh''' utility.

|-
| 00:55
|The steps are as follows-
Step 1 : Create a '''base mesh''' by using '''blockMesh''' utility
Step 2 : Refine '''base mesh'''
Step 3 : Remove unused '''cells'''
Step 4 : '''Snap mesh''' to surface
Step 5 : Add layers

|-
| 01:18
| We will open the '''terminal '''and enter the path for '''flange '''as shown.
Type '''cd OpenFOAM-2.2.2/tutorials/mesh/snappyHexMesh/flange''' and press '''Enter'''.

|-
| 01:40
| Now type '''ls''' and press '''Enter.'''There are two folders '''constant '''and '''system'''.

|-
| 01:50
| Type '''cd space system''' and press '''Enter.'''

|-
| 01:55
| Now type '''ls''' and press '''Enter.'''You can see '''snappyHexMeshDict '''file.

|-
| 02:04
| To view the contents of the file type -'''gedit snappyHexMeshDict '''and press '''Enter.'''
(Note that H, M and D here are in capital letters.)

|-
| 02:19
| This will open up the '''snappyHexMeshDict''' file.

|-
| 02:23
| '''snappyHexMeshDict''' file contains all the instructions and the entire process revolves around this file.

|-
| 02:32
| With the first rows of '''snappyHexMeshDict, '''you can activate or skip sections of the process.

|-
| 02:40
| In the '''geometry''' section, all active regions that take part in '''snappy''' process can be defined.

|-
|02:50
| The parameters that govern the process of cell splitting are described in '''castellatedMeshControls''' section.

|-
| 02:58
| The parameters that are listed below are well explained in '''snappyHexMeshDict''' file.'''nCellsBetweenLevels''' defines number of cells for each refinement level.

|-
| 03:12
|The higher it is, the more gradual the '''mesh''' will be.

|-
|03:17
| In the '''Explicit feature edge refinement''' section, you can set specific refinement level for geometry’s feature edges.The''' .eMesh''' file can be obtained with the '''surfaceFeatureExtract '''utility.

|-
| 03:34
| In the '''surface-based refinement '''section, you can set the refinement levels of all surfaces defined in '''geometry''' file.

|-
| 03:45
| Mesh selection is a very important parameter.If the chosen point is inside the surface described in '''geometry''' file, then '''snappyHexMesh''' will create the internal mesh.

|-
| 03:59
|Otherwise the external part (inside the blockMesh) is meshed.

|-
| 04:04
| The next step involves moving cell vertex points onto the surface geometry.

|-
| 04:12
| The '''snapping''' process is carried out by four parameters:
* '''nSmoothPatch'''
* '''tolerance'''
* '''nSolveIter'''
* '''nRelaxIter'''

|-
|04:23
|These parameters control the number of iterations and tolerance between '''mesh''' and '''STL''' surface.

|-
| 04:32
|'''nSmoothPatch '''option specifies the number of times the exterior ( that is the boundary wall) should be iterated.The '''mesh''' will become smoother if the number of iterations are more.

|-
| 04:46
|'''Tolerance''' option specifies the distance the program should look, for a point to '''snap'''.The distance will be the number that is in '''tolerance.'''

|-
| 04:58
| '''nSolveIter '''option specifies the number of times the '''snapping''' part of '''snappyHexMesh '''should be run.

|-
| 05:07
| '''nRelaxIter''' option specifies the number of times the mesh should run a relaxing script, that removes bad '''mesh''' points.

|-
| 05:19
| The process of '''mesh''' layer addition involves shrinking the existing '''mesh''' from the boundary and inserting layers of cells.

|-
| 05:27
|The first group of parameters define the dimensions for layers and surface, on which they will be attached.

|-
| 05:36
| '''RelativeSizes '''option ( that is true or false) changes the way to read the parameters given next.
'''true''': next parameters define the layers' dimensions as parameters.
'''false''': next parameters define directly the layers' dimensions.

|-
| 05:55
| In '''layers''' option, you can define the number of '''layers''' and the patch on which to attach the '''layers'''.It must be an'''Bold text''' STL patch in '''geomery''' sub-menu, and not a user defined region.

|-
| 06:10
| '''ExpansionRatio''' parameters sets the growth factor of the '''layers''' (that is ratio between two subsequent layers).

|-
| 06:19
| '''finalLayerThickness''' parameter sets the thickness of the last layer.'''minThickness''' parameter sets the minimum allowable thickness of layer.

|-
| 06:34
|"'''Advanced settings''' is the second group of parameters.It contains more specific controls that can help in layer creation.

|-
| 06:45
| '''FeatureAngle''' is the angle above which the surface will not be extruded.

|-
| 06:52
| '''nRelaxIter''' option specifies the number of times the mesh will run a relaxing script.

|-
| 07:00
| '''maxFaceThicknessRatio''' option specifiess the maximum allowable value of aspect ratio.

|-
| 07:10
| meshQualityControls parameter sets the minimum thresholds to generate '''mesh''' in '''snap''' and add-layers parts.

|-
| 07:18
|In 99% of the cases, it is better to leave the default values.But sometimes, you can deactivate one or more controls to force mesh generation.

|-
| 07:30
| These are the different parameters in '''snappyHexMeshDict'''.These parameters are important to generate '''mesh''' using '''snappyHexMesh''' utility.

|-
| 07:40
|Let us summarize.

|-
| 07:42
| In this tutorial we learnt Different parameteres in '''snappyHexMesh '''to generate mesh in '''OpenFoam'''.

|-
| 07:50
| Watch the video available at this URLhttp://spoken-tutorial.org/What_is_a_Spoken_Tutorial
It summarizes the Spoken Tutorial project. If you do not have good bandwidth, you can download and watch it.

|-
| 08:03
| The Spoken Tutorial Project TeamConducts workshops using spoken tutorials
Gives certificates to those who pass an online test For more details, please write to
contact@spoken-tutorial.org

|-
| 08:21
| Spoken Tutorials are part of Talk to a Teacher project, It is supported by the National Mission on Education through ICT, MHRD, Government of India. More information on the same is available at following URL link http://spoken-tutorial.org/NMEICT-Intro

|-
| 08:37
| This is Chaitrali Ghodke from IIT BOMBAY signing off.Thanks for joining.

|}

@@ Line 211: / Line 211: @@
 Gives certificates to those who pass an online test.
 For more details, please write to:'''contact@spoken-tutorial.org'''
 |-
 | 08:21

@@ Line 16: / Line 16: @@
 |00:14
 | As a pre-requisite, the user requires:
-* Surface data files in '''STL''' format, located in '''constant/trisurface''' sub-directory of the '''case''' directory
+Surface data files in '''STL''' format, located in '''constant/trisurface''' sub-directory of the '''case''' directory
-* A domain with '''hex mesh'''
+A domain with '''hex mesh'''
-* '''snappyHexMeshDict''' dictionary located in the '''system''' sub-directory of''' case'''.
+'''snappyHexMeshDict''' dictionary located in the '''system''' sub-directory of''' case'''.
 |-
 | 00:35
 | To record this tutorial, I am using:
-* '''Ubuntu Linux operating system''' 12.04
+'''Ubuntu Linux operating system''' 12.04
-* '''OpenFOAM''' version 2.2.2
+'''OpenFOAM''' version 2.2.2
-* '''ParaView''' version 3.12.0
+'''ParaView''' version 3.12.0
 |-
@@ Line 42: / Line 42: @@
 |-
 | 01:18
-| We will open the '''terminal '''and enter the '''path''' for '''flange '''as shown.
+| We will open the '''terminal '''and enter the '''path''' for '''flange '''as shown. Type: '''cd space OpenFOAM-2.2.2/tutorials/mesh/snappyHexMesh/flange''' and press '''Enter'''.
 Type: '''cd space OpenFOAM-2.2.2/tutorials/mesh/snappyHexMesh/flange''' and press '''Enter'''.
 |-
@@ Line 59: / Line 58: @@
 |-
 | 02:04
-| To view the contents of the file, type: -'''gedit space snappyHexMeshDict '''and press '''Enter.'''
+| To view the contents of the file, type: -'''gedit space snappyHexMeshDict '''and press '''Enter.'''(Note that H, M and D here are in capital letters.)
 (Note that H, M and D here are in capital letters.)
 |-
@@ Line 113: / Line 111: @@
 | 04:12
 | The '''snapping''' process is carried out by four parameters:
-* '''nSmoothPatch'''
+'''nSmoothPatch'''
-* '''tolerance'''
+'''tolerance'''
-* '''nSolveIter'''
+'''nSolveIter'''
-* '''nRelaxIter'''.
+'''nRelaxIter'''.
 |-
@@ Line 210: / Line 208: @@
 | 08:03
 | The Spoken Tutorial Project team:
-* Conducts workshops using spoken tutorials.
+Conducts workshops using spoken tutorials.
-* Gives certificates to those who pass an online test.
+Gives certificates to those who pass an online test.
-For more details, please write to:
+For more details, please write to:'''contact@spoken-tutorial.org'''
 '''contact@spoken-tutorial.org'''
 |-
 | 08:21

@@ Line 84: / Line 84: @@
 |-
 | 02:58
-| The parameters that are listed below are well explained in '''snappyHexMeshDict''' file. '''nCellsBetweenLevels''' defines number of cells for each refinement level.
+| The parameters that are listed below are well explained in '''snappyHexMeshDict''' file. '''nCellsBetweenLevels''' defines the number of cells for each refinement level.
 |-
@@ Line 104: / Line 104: @@
 |-
 | 03:59
-|Otherwise the external part (i.e. inside the blockMesh) is meshed.
+|Otherwise, the external part (i.e. inside the blockMesh) is meshed.
 |-
 | 04:04
-| The next step involves moving cell vertex points onto the surface geometry.
+| The next step involves moving '''cell''' vertex points onto the surface geometry.
 |-
@@ Line 120: / Line 120: @@
 |-
 |04:23
-|These parameters control the number of iterations and tolerance between '''mesh''' and '''STL''' surface.
+|These parameters control the number of '''iterations''' and '''tolerance''' between '''mesh''' and '''STL''' surface.
 |-
 | 04:32
-|'''nSmoothPatch '''option specifies the number of times the exterior ( that is the boundary wall) should be iterated. The '''mesh''' will become smoother if the number of iterations are more.
+|'''nSmoothPatch '''option specifies the number of times the exterior (that is the boundary wall) should be iterated. The '''mesh''' will become smoother if the number of iterations are more.
 |-
@@ Line 140: / Line 140: @@
 |-
 | 05:19
-| The process of '''mesh''' layer addition involves shrinking the existing '''mesh''' from the boundary and inserting layers of cells.
+| The process of '''mesh layer''' addition involves shrinking the existing '''mesh''' from the boundary and inserting layers of '''cell'''s.
 |-
@@ Line 148: / Line 148: @@
 |-
 | 05:36
-| '''RelativeSizes '''option ( that is true or false) changes the way to read the parameters given next.
+| '''RelativeSizes '''option (that is '''true''' or '''false''') changes the way to read the parameters given next.
 '''true''': next parameters define the layers' dimensions as parameters.
 '''false''': next parameters define directly the layers' dimensions.
@@ Line 154: / Line 154: @@
 |-
 | 05:55
-| In '''layers''' option, you can define the number of '''layers''' and the '''patch''' on which to attach the '''layers'''. It must be an STL (Bold text)  patch in '''geomery''' sub-menu, and not a user defined region.
+| In '''layers''' option, you can define the number of '''layers''' and the '''patch''' on which to attach the '''layers'''. It must be an '''STL''' (Bold text)  patch in '''geomery''' sub-menu, and not a user defined region.
 |-
@@ Line 178: / Line 178: @@
 |-
 | 07:00
-| '''maxFaceThicknessRatio''' option specifiess the maximum allowable value of '''aspect ratio'''.
+| '''maxFaceThicknessRatio''' option specifies the maximum allowable value of '''aspect ratio'''.
 |-
 | 07:10
-| meshQualityControls parameter sets the minimum thresholds to generate '''mesh''' in '''snap''' and '''add-layers''' parts.
+| '''meshQualityControls''' parameter sets the minimum thresholds to generate '''mesh''' in '''snap''' and '''add-layers''' parts.
 |-
 | 07:18
-|In 99% of the cases, it is better to leave the default values. But sometimes, you can '''deactivate''' one or more controls to force mesh generation.
+|In 99% of the cases, it is better to leave the '''default''' values. But sometimes, you can '''deactivate''' one or more controls to force mesh generation.
 |-

@@ Line 136: / Line 136: @@
 |-
 | 05:07
-| '''nRelaxIter''' option specifies the number of times the mesh should run a relaxing script, that removes bad '''mesh''' points.
+| '''nRelaxIter''' option specifies the number of times the mesh should '''run''' a relaxing script, that removes bad '''mesh''' points.
 |-
@@ Line 154: / Line 154: @@
 |-
 | 05:55
-| In '''layers''' option, you can define the number of '''layers''' and the patch on which to attach the '''layers'''.It must be an'''Bold text''' STL patch in '''geomery''' sub-menu, and not a user defined region.
+| In '''layers''' option, you can define the number of '''layers''' and the '''patch''' on which to attach the '''layers'''. It must be an STL (Bold text)  patch in '''geomery''' sub-menu, and not a user defined region.
 |-
 | 06:10
-| '''ExpansionRatio''' parameters sets the growth factor of the '''layers''' (that is ratio between two subsequent layers).
+| '''ExpansionRatio''' parameters set the growth factor of the '''layers''' (that is ratio between two subsequent layers).
 |-
 | 06:19
-| '''finalLayerThickness''' parameter sets the thickness of the last layer.'''minThickness''' parameter sets the minimum allowable thickness of layer.
+| '''finalLayerThickness''' parameter sets the thickness of the last layer. '''minThickness''' parameter sets the minimum allowable thickness of layer.
 |-
 | 06:34
-|"'''Advanced settings''' is the second group of parameters.It contains more specific controls that can help in layer creation.
+|'''Advanced settings''' is the second group of parameters. It contains more specific controls that can help in layer creation.
 |-
@@ Line 174: / Line 174: @@
 |-
 | 06:52
-| '''nRelaxIter''' option specifies the number of times the mesh will run a relaxing script.
+| '''nRelaxIter''' option specifies the number of times the '''mesh''' will '''run''' a relaxing script.
 |-
 | 07:00
-| '''maxFaceThicknessRatio''' option specifiess the maximum allowable value of aspect ratio.
+| '''maxFaceThicknessRatio''' option specifiess the maximum allowable value of '''aspect ratio'''.
 |-
 | 07:10
-| meshQualityControls parameter sets the minimum thresholds to generate '''mesh''' in '''snap''' and add-layers parts.
+| meshQualityControls parameter sets the minimum thresholds to generate '''mesh''' in '''snap''' and '''add-layers''' parts.
 |-
 | 07:18
-|In 99% of the cases, it is better to leave the default values.But sometimes, you can deactivate one or more controls to force mesh generation.
+|In 99% of the cases, it is better to leave the default values. But sometimes, you can '''deactivate''' one or more controls to force mesh generation.
 |-
 | 07:30
-| These are the different parameters in '''snappyHexMeshDict'''.These parameters are important to generate '''mesh''' using '''snappyHexMesh''' utility.
+| These are the different parameters in '''snappyHexMeshDict'''. These parameters are important to generate '''mesh''' using '''snappyHexMesh''' utility.
 |-
@@ Line 198: / Line 198: @@
 |-
 | 07:42
-| In this tutorial we learnt Different parameteres in '''snappyHexMesh '''to generate mesh in '''OpenFoam'''.
+| In this tutorial, we learnt different parameters in '''snappyHexMesh '''to generate mesh in '''OpenFoam'''.
 |-
 | 07:50
-| Watch the video available at this URLhttp://spoken-tutorial.org/What_is_a_Spoken_Tutorial
+| Watch the video available at this URL:
-It summarizes the Spoken Tutorial project. If you do not have good bandwidth, you can download and watch it.
+http://spoken-tutorial.org/What_is_a_Spoken_Tutorial
 |-
 | 08:03
-| The Spoken Tutorial Project TeamConducts workshops using spoken tutorials
+| The Spoken Tutorial Project team:
-Gives certificates to those who pass an online test For more details, please write to
+* Conducts workshops using spoken tutorials.
-contact@spoken-tutorial.org
+* Gives certificates to those who pass an online test.
+For more details, please write to:
 |-
 | 08:21
-| Spoken Tutorials are part of Talk to a Teacher project, It is supported by the National Mission on Education through ICT, MHRD, Government of India. More information on the same is available at following URL link http://spoken-tutorial.org/NMEICT-Intro
+| '''Spoken Tutorial'''s are part of '''Talk to a Teacher''' project. It is supported by the National Mission on Education through ICT, MHRD, Government of India.
 |-
 | 08:37
-| This is Chaitrali Ghodke from IIT BOMBAY signing off.Thanks for joining.
+| This is Chaitrali Ghodke from '''IIT Bombay''', signing off. Thanks for joining.
 |}

@@ Line 5: / Line 5: @@
 |-
 | 00:00
-| Hello and welcome to the spoken tutorial on Introduction to '''snappyHexMesh''' in '''OpenFOAM'''.
+| Hello and welcome to the '''spoken tutorial''' on '''Introduction to snappyHexMesh''' in '''OpenFOAM'''.
 |-
 | 00:07
 | In this tutorial, we will learn about
-The parameters in '''snappyHexMesh'''
+the parameters in '''snappyHexMesh'''
-To generate '''Mesh''' in '''OpenFOAM'''.
+to generate '''Mesh''' in '''OpenFOAM'''.
 |-
 |00:14
-| As a pre-requisite, the user requires
+| As a pre-requisite, the user requires:
 * Surface data files in '''STL''' format, located in '''constant/trisurface''' sub-directory of the '''case''' directory
 * A domain with '''hex mesh'''
-* '''snappyHexMeshDict''' dictionary located in the '''system''' sub-directory of''' case'''
+* '''snappyHexMeshDict''' dictionary located in the '''system''' sub-directory of''' case'''.
 |-
 | 00:35
-| To record this tutorial, I am using
+| To record this tutorial, I am using:
-* '''Ubuntu Linux''' operating system 12.04
+* '''Ubuntu Linux operating system''' 12.04
 * '''OpenFOAM''' version 2.2.2
 * '''ParaView''' version 3.12.0
@@ Line 29: / Line 29: @@
 |-
 | 00:50
-| Let us learn to create a Mesh with the '''snappyHexMesh''' utility.
+| Let us learn to create a '''Mesh''' with the '''snappyHexMesh''' utility.
 |-
@@ Line 38: / Line 38: @@
 Step 3 : Remove unused '''cells'''
 Step 4 : '''Snap mesh''' to surface
-Step 5 : Add layers
+Step 5 : Add '''layers'''.
 |-
 | 01:18
-| We will open the '''terminal '''and enter the path for '''flange '''as shown.
+| We will open the '''terminal '''and enter the '''path''' for '''flange '''as shown.
-Type '''cd OpenFOAM-2.2.2/tutorials/mesh/snappyHexMesh/flange''' and press '''Enter'''.
+Type: '''cd space OpenFOAM-2.2.2/tutorials/mesh/snappyHexMesh/flange''' and press '''Enter'''.
 |-
 | 01:40
-| Now type '''ls''' and press '''Enter.'''There are two folders '''constant '''and '''system'''.
+| Now type "ls" and press '''Enter.''' There are two folders '''constant '''and '''system'''.
 |-
@@ Line 55: / Line 55: @@
 |-
 | 01:55
-| Now type '''ls''' and press '''Enter.'''You can see '''snappyHexMeshDict '''file.
+| Now type '''ls''' and press '''Enter.''' You can see '''snappyHexMeshDict '''file.
 |-
 | 02:04
-| To view the contents of the file type -'''gedit snappyHexMeshDict '''and press '''Enter.'''
+| To view the contents of the file, type: -'''gedit space snappyHexMeshDict '''and press '''Enter.'''
 (Note that H, M and D here are in capital letters.)
@@ Line 80: / Line 80: @@
 |-
 |02:50
-| The parameters that govern the process of cell splitting are described in '''castellatedMeshControls''' section.
+| The '''parameter'''s that govern the process of cell splitting are described in '''castellatedMeshControls''' section.
 |-
 | 02:58
-| The parameters that are listed below are well explained in '''snappyHexMeshDict''' file.'''nCellsBetweenLevels''' defines number of cells for each refinement level.
+| The parameters that are listed below are well explained in '''snappyHexMeshDict''' file. '''nCellsBetweenLevels''' defines number of cells for each refinement level.
 |-
@@ Line 92: / Line 92: @@
 |-
 |03:17
-| In the '''Explicit feature edge refinement''' section, you can set specific refinement level for geometry’s feature edges.The''' .eMesh''' file can be obtained with the '''surfaceFeatureExtract '''utility.
+| In the '''Explicit feature edge refinement''' section, you can set specific refinement level for geometry’s feature edges. The ".eMesh" file can be obtained with the '''surfaceFeatureExtract '''utility.
 |-
@@ Line 100: / Line 100: @@
 |-
 | 03:45
-| Mesh selection is a very important parameter.If the chosen point is inside the surface described in '''geometry''' file, then '''snappyHexMesh''' will create the internal mesh.
+| '''Mesh selection''' is a very important parameter. If the chosen point is inside the surface described in '''geometry''' file, then '''snappyHexMesh''' will create the internal mesh.
 |-
 | 03:59
-|Otherwise the external part (inside the blockMesh) is meshed.
+|Otherwise the external part (i.e. inside the blockMesh) is meshed.
 |-
@@ Line 116: / Line 116: @@
 * '''tolerance'''
 * '''nSolveIter'''
-* '''nRelaxIter'''
+* '''nRelaxIter'''.
 |-
@@ Line 124: / Line 124: @@
 |-
 | 04:32
-|'''nSmoothPatch '''option specifies the number of times the exterior ( that is the boundary wall) should be iterated.The '''mesh''' will become smoother if the number of iterations are more.
+|'''nSmoothPatch '''option specifies the number of times the exterior ( that is the boundary wall) should be iterated. The '''mesh''' will become smoother if the number of iterations are more.
 |-
 | 04:46
-|'''Tolerance''' option specifies the distance the program should look, for a point to '''snap'''.The distance will be the number that is in '''tolerance.'''
+|'''Tolerance''' option specifies the distance the program should look for a point to '''snap'''. The distance will be the number that is in '''tolerance.'''
 |-
 | 04:58
-| '''nSolveIter '''option specifies the number of times the '''snapping''' part of '''snappyHexMesh '''should be run.
+| '''nSolveIter '''option specifies the number of times the '''snapping''' part of '''snappyHexMesh '''should be '''run'''.
 |-