CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > Siemens > STAR-CCM+

Drag force coefficient too low for a flow past cylinder at Re= 1e05

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 18, 2014, 16:43
Default Drag force coefficient too low for a flow past cylinder at Re= 1e05
  #1
Member
 
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13
Scabbard is on a distinguished road
Dear all,

I just start to use Star-ccm+. I try to simulate a flow past a stationary cylinder at Re=1e05. However, the result I got is quite different from the experiment. The previous experiment shows the Cd is around 1.1, my simulation result is around 0.55.

Here is the information of my cases,

Mesh:

cylinder diameter: 0.1m
flow velocity:1m/s
Re=1e05
Thickness of near wall prism layer 2e-05 (y+=1)
Aref 0.0314m/s^2 (the front area, my cylinder height is 0.314m)
timestep 0.0005s
simulation time: 10s

The flow inlet boundary is located 10D upstream from the centre of the cylinder and the flow outlet boundary is located 25D downstream from the center of the cylinder. The top and bottom boundaries are located at a distance of 10D from the center of the cylinder.

Mesh picture is in attached.


Models:
Three Dimensional
Gradient
Implicit Unsteady
Liquid (H2O)
Segregated flow
Constant density
Turbulent
Large Eddy Simulation
Dynamic Smagorinsky Sugird Scale
Low y+ Wall Treatment

Cd properties
Coordinate System : Laboratory
Direction:[1.0,0.0,0.0]
Force Option:Pressure+Shear ( I try only Pressure but there is no different and I don't know which option should I choose)
Reference Pressure: 0Pa
Reference Density: 997.561kg/m^3
Reference Velocity: 1m/s
Reference Area:0.0314m^2
Parts: cylinder

Boundary

cylinder: no-slip wall
inlet:velocity inlet
outlet pressure outlet
front,back,top, down: symmetry

I make first several time step interaction 150, the change it to 20, make the continuity residual close to 1e-04

I try the mesh polyheral mesh with 70w cell however the Cd is 0.55 which just half of the experiment result.

Could Anyone give me some recommendations about which setting is wrong in my case?
Many thank with your kindly help.

Here is my simulation case, I am using version 9.04.011-R8
https://docs.google.com/file/d/0B1v8...RmclRscHM/edit



Best Regards,
Scabbard
Attached Images
File Type: jpg Capture.jpg (46.3 KB, 58 views)
File Type: jpg Capture1.jpg (33.5 KB, 49 views)

Last edited by Scabbard; October 22, 2014 at 19:09.
Scabbard is offline   Reply With Quote

Old   October 22, 2014, 19:09
Unhappy
  #2
Member
 
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13
Scabbard is on a distinguished road
Dear all,

Here is another discussion I posted about this problem.
http://www.cfd-online.com/Forums/mai...tml#post515042

I try several method (URANS, LES, different mesh )about simulating this. every time I got Cd around 0.5.

Could anyone help me find where is the mistake I made? I am really sick with this problem now.

Many thanks,

Best Regards,
Scabbard
Scabbard is offline   Reply With Quote

Old   June 5, 2020, 15:44
Default
  #3
Member
 
Gang Wang
Join Date: Oct 2019
Location: China
Posts: 64
Rep Power: 8
Gang Wang is on a distinguished road
Quote:
Originally Posted by Scabbard View Post
Dear all,

Here is another discussion I posted about this problem.
http://www.cfd-online.com/Forums/mai...tml#post515042

I try several method (URANS, LES, different mesh )about simulating this. every time I got Cd around 0.5.

Could anyone help me find where is the mistake I made? I am really sick with this problem now.

Many thanks,

Best Regards,
Scabbard
Hi!

Did you solve this problem? I'm also troubled with this problem. I know it's quite an old post but I'm still wondering....

Could you please share the solution and thinking with me?

Best
Gang
Gang Wang 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
ActuatorDiskExplicitForce in OF2.1. Help be_inspired OpenFOAM Programming & Development 10 September 14, 2018 12:12
Modelling flow around a Smooth Cylinder - Drag coefficient HELP Asatorae STAR-CCM+ 17 November 14, 2014 11:45
Laminar flow over a cylinder_lift and drag coefficient ssmeherk OpenFOAM 0 February 18, 2014 08:29
Flow past rotating cylinder: Problem with ForeCoeffs raf1111 OpenFOAM 1 December 16, 2013 10:45
plotting drag coefficient in low reynolds number flow past cylinder atmcfd FLUENT 0 January 2, 2010 09:34


All times are GMT -4. The time now is 05:26.