CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > ANSYS Meshing & Geometry

[DesignModeler] Thin Surfaces or 3D solid model?

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 14, 2016, 19:11
Default Thin Surfaces or 3D solid model?
  #1
Member
 
Ferruccio Rossi
Join Date: Jun 2016
Location: Melbourne, FL USA
Posts: 91
Rep Power: 10
frossi is on a distinguished road
Hi everybody,

I am a college student learning Ansys and CFD. I am running a two-ways FSI simulation of a wing with Transient Structural and CFX (the wing is hollow inside with a skin thickness of 0.5 inches). I used one side of the wing as the fixed support. The goal is to find the equivalent stress and the deformation of the wing.

First, I modeled the geometry using the thin surface option. I used 3 different surfaces: the wing skin, the support (where it attaches to the fuselage), and the wingtip surface. I set the surfaces thickness offset type to "middle" (This causes the mesh of the skin to merge with the mesh of the support and wingtip. Is this a problem?)
When I look at the FSI results, I get a deformation of about 2 cm, and an equivalent stress of 37 MPa.
Then, to check my results, I ran the same FSI simulation with a 3D hollow body of the same wing imported from Creo. The equivalent stress is very similar (35 MPa) but the deformation is much larger (23 cm!!!).

I believe this is due to the different geometries in the Modeler, because everything else is exactly the same. Could someone please explain me why I get such a big difference in the deformation, while the stress is almost the same?
Also, when is it appropriate to use thin surfaces, and when is it better to use 3D solid bodies?

The first two pics show the thin surface wing, while the last two pics show the 3D solid body wing.



I am stuck and would really appreciate some help. Thank you very much!
Attached Images
File Type: png 1.png (23.6 KB, 12 views)
File Type: png 2.png (21.4 KB, 11 views)
File Type: png 3.png (46.4 KB, 11 views)
File Type: png 4.png (31.7 KB, 11 views)
frossi is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
Radiation in semi-transparent media with surface-to-surface model? mpeppels CFX 11 August 22, 2019 08:30
Y+ and first layer height in a model with thin features assafwei Main CFD Forum 0 May 4, 2014 18:37
Simulation of a Silo Attesz CFX 20 October 15, 2010 09:11
2D Meshing - No matter how thin my model is, it is still 2 elements thick RossFS ANSYS Meshing & Geometry 6 April 14, 2010 01:13
convergency problem with Solid Pressure Model commonyue Main CFD Forum 0 March 30, 2010 06:18


All times are GMT -4. The time now is 03:32.