Unable to validate Drag coefficient for Flow past a sphere using OpenFOAM
 

Hi Foamers,

I am new to pimpleFoam / OpenFOAM and was trying to validate the overall drag on a sphere due to a flow past it. I am aware of a thread closely related: https://www.cfd-online.com/Forums/op...tml#post864018. There are other threads too but none speaks of validation at low Reynolds number (creeping) flows with Cd=24/Re.
I have followed the above link to build my case. I used the entries as stated in the link with the given geometry, I am not getting the drag coefficient of 27.6, I am getting something around 40. I have attached my case, it would be helpful if anyone could spot where I am going wrong or share any comment that would help me validate the same. Additionally, is there a 3D version for validating Cd for flow past a sphere in OpenFOAM?

PS: To run the case, one has to convert the .geo file in constant to .msh using GMSH and then use the two following commands:
In case GMSH is not available, kindly drop a reply, and I will share the files over a link.

Thanks in anticipation,
JD

Hello jd87,
Just wanted to ask if you tried getting the drag force from paraview and then tried calculating Cd from there?

Regards

Hi,

I have used the forcesCoeff utility (you may find that in the controlDict file). I tried previously with paraView, but I did not get the desired results, hence attempted to use the internal OpenFOAM utility.
Let me know if you have any ideas regarding this problem.

Thanks,
JD

hello,
Sure, if i'm able to find anything on this, i'll let you know...

regards

Succesfully verified
 

The problem is solved and the files are attached for future help. The file is checked to run on OF v8 and v10.

Best,