CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Mesh Generation & Pre-Processing Software > Pointwise & Gridgen

Hybrid Meshing for horizontal axis wind turbine

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   September 8, 2014, 18:11
Default Hybrid Meshing for horizontal axis wind turbine
  #1
New Member
 
Eslam Hashem Mohamed
Join Date: Oct 2013
Location: Cairo,Egypt
Posts: 13
Rep Power: 12
Eslam Hashem is on a distinguished road
there is a webinar about Hybrid Meshing for horizontal axis wind turbine, after watching i have some questions about the video showed
i am asking what is the rotating part here, is that the inner block or the blade it self ?

if the inner block becomes the rotating part, the solid model of the blade should be subtracted from the inner block. does the subtract operation done in pointwise and if it's true how to subtract using pointwise?
i usually do this operation in design modeler

https://www.youtube.com/watch?v=KOvW...uIeHrz1i2GI1lg
Eslam Hashem is offline   Reply With Quote

Old   September 8, 2014, 20:12
Default
  #2
Senior Member
 
Travis Carrigan
Join Date: Jul 2010
Location: Arlington, TX
Posts: 161
Rep Power: 15
tcarrigan is on a distinguished road
Hello Eslam,

I'm happy to answer your questions. I put together this video a few years ago and am very familiar with the process for generating this grid.

The rotating zone is the inner block being assembled around the 29:00 minute mark in the video. This is setup to be run unsteady with a sliding inner zone and stationary outer zone.

I should clarify here, this is a CFD mesh. There is no mesh of the solid blade, only a surface mesh. If you watch the beginning of the video you'll see me generating the surface mesh for the rotor. Once the surface mesh has been defined and the boundaries of the rotating zone, the block assembly operation I perform around the 29:00 minute mark demonstrates how the grid is formed. So essentially, yes, this operation does subtract the blade from the rotating zone and what you're left with is the fluid region surrounding the blade.

Travis
__________________
Travis Carrigan
Manager, Business Development
Pointwise, Inc.
tcarrigan is offline   Reply With Quote

Old   September 8, 2014, 21:55
Default
  #3
New Member
 
Eslam Hashem Mohamed
Join Date: Oct 2013
Location: Cairo,Egypt
Posts: 13
Rep Power: 12
Eslam Hashem is on a distinguished road
Hello Mr.Travis Carrigan,
Really the happy person is me to see your reply Mr. Carrigan the one who made this grid and Senior engineer in Pointwise Inc. I'm so grateful for your reply and for this Webinar which help me in learning meshing using pointwise. After your helpful reply i can say that in pointwise we don't to a boolean operations such as subtract as most of people with other grid generators "Ansys DesignModeler+Ansys Mesher" , and ICEM. but i noticed that your rotor is a surface model not a solid model. i asked if is there any problem with dealing with solid rotor for example?
secondly, i can say that the rotating zone that you mean is the unstructured block containing both blade and wake block which is initialized in 30:11 under the name of blk-14 is that true?
I want to ask if the inner and outer blocks are sketched using pointwise or by another software like DesignModeler then they imported into pointwise since it s appearing that the hub is subtracted from the inner block and the inner block is subtracted from the outer block as shown in pictures below.
I'm sorry for my long reply and questions and i will be so grateful to see your reply Mr. Carrigan

Best Regards,
Eslam
Attached Images
File Type: jpg 1.jpg (18.2 KB, 37 views)
File Type: jpg 2.jpg (10.1 KB, 27 views)
File Type: jpg 3.jpg (24.9 KB, 29 views)
Eslam Hashem is offline   Reply With Quote

Old   September 9, 2014, 09:02
Default
  #4
Senior Member
 
Travis Carrigan
Join Date: Jul 2010
Location: Arlington, TX
Posts: 161
Rep Power: 15
tcarrigan is on a distinguished road
Eslam,

There should be no problem when dealing with a solid model for the rotor. And you are correct, blk-14 is the block I'm referring to that contains the blade and the wake block. You can see how it was defined earlier in the video.

The inner and outer block geometry seen in your pictures was sketched entirely within Pointwise. Pointwise contains several CAD tools in the Create menu for sketching geometric (database) curves and surfaces. I simply imported just the rotor model and sketched the remainder of my farfield by hand.

Travis
__________________
Travis Carrigan
Manager, Business Development
Pointwise, Inc.
tcarrigan is offline   Reply With Quote

Old   September 10, 2014, 16:24
Default
  #5
New Member
 
Eslam Hashem Mohamed
Join Date: Oct 2013
Location: Cairo,Egypt
Posts: 13
Rep Power: 12
Eslam Hashem is on a distinguished road
Thanks Mr. Tcarrigan for your reply. You have illustrated many issues for me which can help me in my task. Really, i'm grateful for your help.

Eslam
Eslam Hashem is offline   Reply With Quote

Old   September 11, 2014, 14:02
Default
  #6
New Member
 
Eslam Hashem Mohamed
Join Date: Oct 2013
Location: Cairo,Egypt
Posts: 13
Rep Power: 12
Eslam Hashem is on a distinguished road
Sorry Mr.Travis for asking again, I tried to sketch the inner and outer blocks entirely by using Pointwise through database lines [Create-Draw Curves-line-On Database] and they were sketched but I wish to get a Quilt not a single Database lines. I want to get qulits as shown in this tutorial [Video] and i don't know how to convert these Database lines into Quilts or the Quilt should be created from the beginning. I know that I'm asking many questions but i need your help Mr.Travis.

Eslam
Eslam Hashem is offline   Reply With Quote

Old   September 11, 2014, 14:04
Default
  #7
Senior Member
 
Travis Carrigan
Join Date: Jul 2010
Location: Arlington, TX
Posts: 161
Rep Power: 15
tcarrigan is on a distinguished road
You can use the database lines you've just created to generate a coons patch. You can create either interpolated surfaces or coons patches from the Create menu in Pointwise.
__________________
Travis Carrigan
Manager, Business Development
Pointwise, Inc.
tcarrigan is offline   Reply With Quote

Old   September 15, 2014, 14:52
Default
  #8
New Member
 
Eslam Hashem Mohamed
Join Date: Oct 2013
Location: Cairo,Egypt
Posts: 13
Rep Power: 12
Eslam Hashem is on a distinguished road
When i tried to extrude the surface mesh of NREL Phase VI wind turbine blade like that was done in the video in min 17:10. I did the steps one by one but Pointwise told me that some cells met the positive skewness stop condition.
this is a link for my PW file
Initial delta s =0.1
Growth rate =1.1
Number of steps =25


http://www.4shared.com/file/ICj8Wv_q..._6-28__1_.html
Attached Images
File Type: jpg 1.jpg (52.9 KB, 47 views)

Last edited by Eslam Hashem; September 15, 2014 at 16:11.
Eslam Hashem is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Vertical Axis Wind Turbine PiotrekL1 Autodesk Simulation CFD 3 May 29, 2013 14:20
Wind Turbine (Periodic Faces Meshing Problems) Seancooke89 Mesh Generation & Pre-Processing 1 March 16, 2013 10:39
Vertical axis wind turbine simulation vincentwks ANSYS 0 April 10, 2012 04:27
3 bladed Vertical Axis Wind Turbine transient CFD ArslanOZCAN FLUENT 1 February 5, 2011 08:34
Reversed flow in Vertical axis wind turbine Anonymized_JL1 FLUENT 0 April 16, 2010 23:20


All times are GMT -4. The time now is 04:07.