CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

Flow over a plate

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

Like Tree2Likes
  • 1 Post By FMDenaro
  • 1 Post By FMDenaro

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 29, 2018, 11:22
Post Flow over a plate
  #1
Member
 
Vivek
Join Date: Mar 2018
Location: India
Posts: 54
Rep Power: 8
vivek05 is on a distinguished road
Hi everyone,
I have one clarification about flow over a flat plate. I had searched in online but i am not clear till now.
Why the leading edge of flat plate has sharp corner in the simulation of flow over a flat plate ?
Why not other shapes?

Thanks in advance!!
vivek05 is offline   Reply With Quote

Old   June 29, 2018, 12:31
Default
  #2
Senior Member
 
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 6,893
Rep Power: 73
FMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura about
Quote:
Originally Posted by vivek05 View Post
Hi everyone,
I have one clarification about flow over a flat plate. I had searched in online but i am not clear till now.
Why the leading edge of flat plate has sharp corner in the simulation of flow over a flat plate ?
Why not other shapes?

Thanks in advance!!



In the theory of developing boundary layer (Prandtl equations), the point x=0 is a point of singularity in the solution. When we solve numerically, the spatial discretization cannot distinguish exactly on a node where the origin is.


If you want to consider a smooth body describing the leading edge, this is developed in a different theory for the BL.
vivek05 likes this.
FMDenaro is offline   Reply With Quote

Old   June 29, 2018, 13:07
Default
  #3
Member
 
Vivek
Join Date: Mar 2018
Location: India
Posts: 54
Rep Power: 8
vivek05 is on a distinguished road
Quote:
Originally Posted by FMDenaro View Post
In the theory of developing boundary layer (Prandtl equations), the point x=0 is a point of singularity in the solution. When we solve numerically, the spatial discretization cannot distinguish exactly on a node where the origin is.


If you want to consider a smooth body describing the leading edge, this is developed in a different theory for the BL.
Thank you FMDenaro .. what i understood from your reply is ,to locate a node numerically we are using sharp corners because if we used curved leading edge then its difficult to locate a node numerically. is it correct??
vivek05 is offline   Reply With Quote

Old   June 29, 2018, 13:33
Default
  #4
Senior Member
 
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 6,893
Rep Power: 73
FMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura about
Quote:
Originally Posted by vivek05 View Post
Thank you FMDenaro .. what i understood from your reply is ,to locate a node numerically we are using sharp corners because if we used curved leading edge then its difficult to locate a node numerically. is it correct??



No, what I mean is that the BL theory over a flat plate consider really a semi-infinite plat with zero thickness.

On the other hand, on a numerical grid of size h, you can set the first node with no-slip condition but owing to the discretization that does not determine exactly the singular point in the origin.
If you want to describe a slender flat with a rounded leading edge, the standard theory of Prandtl should be modified by the developing boundary layer over the rounded leading edge. If I am right, that theory was developed by Hinze who described an exact solution for small values of x.
vivek05 likes this.
FMDenaro is offline   Reply With Quote

Reply

Tags
flat plate, sharp corner

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
Flow over a heated flat plate: non-physical solution Sushobhan OpenFOAM Running, Solving & CFD 0 May 5, 2018 00:43
Coherent structure for LES simulation of flow past plate with Re=50000 Bashar OpenFOAM 1 December 22, 2016 08:50
flow over a plat and study of temperature distribution in plate and flow Sufyan FLUENT 0 October 16, 2012 04:38
results for flow past flat plate normal to flow lisa Main CFD Forum 2 August 30, 2005 17:36
Supersonic flow over flat plate - best model Chris Rand FLUENT 4 October 3, 2000 07:58


All times are GMT -4. The time now is 21:31.