CFD Online Logo CFD Online URL
Home > Forums > Main CFD Forum

2D vs 3D simulation

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

LinkBack Thread Tools Display Modes
Old   July 18, 2011, 09:29
Smile 2D vs 3D simulation
New Member
Join Date: Feb 2011
Posts: 8
Rep Power: 8
trieuminh07 is on a distinguished road
Can anyone tell me what is different between 2D and 3D simulation? (about math, not complexity)
trieuminh07 is offline   Reply With Quote

Old   July 20, 2011, 16:41
Senior Member
truffaldino's Avatar
Join Date: Jan 2011
Posts: 248
Blog Entries: 5
Rep Power: 10
truffaldino is on a distinguished road
For large reynolds numbers, there is no turbulence due to absence of vortex tube stretching in 2D (i.e. there is no turbulence in 3D sence there, but an inverse cascade). The 2D equation for vorticity is just dw/dt=0, that is why 3D simulation is needed (in absence of turbulence moelling, which is often doubtful) to get more or less meaningful results in CFD.
truffaldino is offline   Reply With Quote

Old   July 22, 2011, 17:49
New Member
Join Date: Jul 2011
Posts: 6
Rep Power: 8
vxv is on a distinguished road
2D simulation is just an idealization of 3D simulation. Consider a flow over a delta wing. Usually, the delta wing taper towards wing tip. If one makes several 2D cuts along spanwise direction, the flow field for each of these cuts will look different. Now, consider a rectangular wing that does not taper towards the tips and has same cross-section all along the span. If the spanwise length is "long enough", and one makes similar 2D cuts along spanwise direction again, the flow field for each of the cuts (not very near the wing tip) will look the same. Ideally, such a flow can be simulated as a 2D flow, because the flow field is independent of one of the directions (in this case spanwise direction).
vxv is offline   Reply With Quote

Old   July 24, 2011, 05:33
New Member
Join Date: Jul 2011
Posts: 29
Rep Power: 8
VincentD is on a distinguished road
You should imagine the third dimension of your 2D simulation as infinite. All the properties are constant over this third dimension (dudz = 0, d2udz2=0 dpdz=0 enz..).
VincentD is offline   Reply With Quote


Thread Tools
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 On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Why my simulation not agree with the wind tunnel experiment zhaowei CFX 4 July 11, 2015 03:36
Solar Radiation in OpenFOAM plainstyle OpenFOAM Running, Solving & CFD 15 July 8, 2014 04:43
Simulation of a complex wing in solidworks flow simulation niels1900 FloEFD, FloWorks & FloTHERM 6 April 20, 2011 10:44
Continuous vs interrupted simulation sega OpenFOAM Running, Solving & CFD 4 November 3, 2008 15:29
strange simulation error Ralf Schmidt FLUENT 2 May 4, 2007 13:02

All times are GMT -4. The time now is 06:16.