CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM

Numerical Computations of Laminar Flow Around a Cylinder

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 12, 2011, 04:57
Default Numerical Computations of Laminar Flow Around a Cylinder
  #1
New Member
 
kob
Join Date: Nov 2011
Posts: 28
Rep Power: 15
bryant_k is on a distinguished road
hello everyone
I have made a simulation of Laminar Flow Around a Cylinder.

My computation domain is 7mx1mx0.025m and the diameter of the cylinder is D = 0.2m.the Reynolds number is defined by Re = UD/nu=40. so I set the inlet velocity U= 1m/s and the density rho=1kg/m3,the kinematic viscosity nu=0.005m2/s. The center of the cylinder is 1.5m away from the left inlet.The third attached file is the reference data of Re=40.In general ,Lw/D is about 2.20~2.29,but my result appeared that Lw/D= 0.3/0.2=1.5

I used the icoFoam solver to simulate the problem. but my result has big differences with the reference paper. I don't know why. Can any body help me? I have attached my case here.


Thank you very much
Best Regards

kob
Attached Images
File Type: jpg my case result t=12s.jpg (76.4 KB, 50 views)
File Type: png paper result.png (39.4 KB, 46 views)
File Type: png reference data.png (6.2 KB, 41 views)

Last edited by bryant_k; November 12, 2011 at 06:42.
bryant_k is offline   Reply With Quote

Old   November 12, 2011, 05:12
Default Numerical Computations of Laminar Flow Around a Cylinder
  #2
New Member
 
kob
Join Date: Nov 2011
Posts: 28
Rep Power: 15
bryant_k is on a distinguished road
I found that i can't attach my case here because the mesh files are a little big.
so i attached the other files here.
Attached Images
File Type: png the model.png (4.4 KB, 28 views)
Attached Files
File Type: zip cyclinder.zip (3.5 KB, 19 views)

Last edited by bryant_k; November 12, 2011 at 06:39.
bryant_k is offline   Reply With Quote

Old   November 12, 2011, 19:46
Default
  #3
Senior Member
 
Martin
Join Date: Oct 2009
Location: Aachen, Germany
Posts: 255
Rep Power: 22
MartinB will become famous soon enough
Hi kob,

I suppose it's your mesh that makes the trouble...

You can try the attached cases: the boundary conditions are yours, I only changed the solvers in fvSolution and added nonOrthogonal correctors.

To run the cases use "blockMesh", than "icoFoam" or "simpleFoam".

Good luck

Martin
Attached Images
File Type: jpg screenshot.jpg (77.4 KB, 35 views)
Attached Files
File Type: gz case_icoFoam_1.7.tar.gz (3.3 KB, 14 views)
File Type: gz case_icoFoam_2.0.x.tar.gz (3.0 KB, 13 views)
File Type: gz case_simpleFoam_1.7.tar.gz (3.3 KB, 9 views)
File Type: gz case_simpleFoam_2.0.x.tar.gz (3.4 KB, 15 views)
MartinB is offline   Reply With Quote

Old   November 12, 2011, 23:13
Post
  #4
New Member
 
kob
Join Date: Nov 2011
Posts: 28
Rep Power: 15
bryant_k is on a distinguished road
Thank you for your attention.I have run your case of case_icofoam1.7 and case_simplefoam1.7.Your result is better than me in large measure but it doesn't match the reference paper very well.Because the Lw is calculated from the right vertex of the cyclinder to the eddy wake not calculated by the way you have used.You can look into the second picture I attached .
bryant_k is offline   Reply With Quote

Old   November 13, 2011, 08:25
Default
  #5
Senior Member
 
Martin
Join Date: Oct 2009
Location: Aachen, Germany
Posts: 255
Rep Power: 22
MartinB will become famous soon enough
You can try a fully developed U inlet profile.

Unpack the attached changeDictionaryDict into the sytem directory.
Usage: "blockMesh", "changeDictionary", "simpleFoam".

Martin
Attached Files
File Type: gz changeDictionaryDict.tar.gz (590 Bytes, 20 views)
MartinB is offline   Reply With Quote

Reply

Tags
flow around a cylinder


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
Incorrect Drag and Drag Coefficient for flow over a cylinder ozzythewise Main CFD Forum 8 June 13, 2012 07:24
Oscillating Cylinder in Parallel Flow: Analytical Solution startingcfd Main CFD Forum 7 March 23, 2012 06:49
Incompressible, Unsteady Cylinder Flow startingcfd Main CFD Forum 1 March 15, 2011 02:12
flow around circular cylinder...plz help yousef FLUENT 4 March 28, 2006 12:01
Flow around a cylinder at subcritical regime. yousef FLUENT 0 March 18, 2006 10:18


All times are GMT -4. The time now is 03:50.