# how should we define the CofR in forceCoeffs function?

 User Name Remember Me Password
 Register Blogs Members List Search Today's Posts Mark Forums Read

 March 9, 2022, 15:05 how should we define the CofR in forceCoeffs function? #1 New Member   Basar H.Ibrahim Join Date: Sep 2021 Posts: 7 Rep Power: 4 Hi, everyone! In the controlDict you can use a function that is defined to give force on the body I want to ask a question about CofR, I know that CofR is a center of rotation. if the Body moves down, how should I set the Cof, still keep a fixed value? Can anyone help me solve the question? PHP Code: ```     forces    {        type            forces;        libs            (forces);        patches         (body);        rhoInf          997;        log             on;        writeControl    timeStep;        writeInterval   1;        CofR            (a b c);    }  ```

 March 9, 2022, 15:10 #2 Senior Member   Join Date: Sep 2013 Posts: 353 Rep Power: 20 It's the point around which your torque will be calculated. Hence if you are only interested in the forces enter whatever maybe (0 0 0). You can calculate the center of gravity of an stl file with the tool surfaceInertia. So depending on your problem you might want to use that. But if you enter (0 0 0) you can obviously always transform that by hand into another point since you will have the torque and force as output. Pasar likes this.

March 9, 2022, 16:05
#3
New Member

Basar H.Ibrahim
Join Date: Sep 2021
Posts: 7
Rep Power: 4
Quote:
 Originally Posted by Bloerb It's the point around which your torque will be calculated. Hence if you are only interested in the forces enter whatever maybe (0 0 0). You can calculate the center of gravity of an stl file with the tool surfaceInertia. So depending on your problem you might want to use that. But if you enter (0 0 0) you can obviously always transform that by hand into another point since you will have the torque and force as output.
Thank you Bloerb for your explanation.
I have a body falls down into the water, so
I want to calculate the pressure of water on the body.

 Tags controldict., functionobject

 Thread Tools Search this Thread Search this Thread: Advanced Search Display Modes Linear Mode

 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 OffTrackbacks are Off Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post [mesh manipulation] refineMesh Error mohsen.boojari OpenFOAM Meshing & Mesh Conversion 3 March 1, 2018 22:07 mdakbari Fluent UDF and Scheme Programming 7 April 4, 2016 04:30 [snappyHexMesh] How to define to right point for locationInMesh Mirage12 OpenFOAM Meshing & Mesh Conversion 7 March 13, 2016 14:07 [blockMesh] Axisymmetrical mesh Rasmus Gjesing (Gjesing) OpenFOAM Meshing & Mesh Conversion 10 April 2, 2007 14:00 brian FLUENT 6 September 11, 2006 08:23

All times are GMT -4. The time now is 04:13.

 Contact Us - CFD Online - Privacy Statement - Top