[jd87]

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: Drag coefficient of sphere & spherical bubble at Re = 1. 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:

gmshToFoam constant/sphere.msh
pimpleFoam

In case GMSH is not available, kindly drop a reply, and I will share the files over a link.

Thanks in anticipation,
JD

[PASCY]

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

Regards

[jd87]

Originally Posted by PASCY

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

[PASCY]

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

regards

[jd87]

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

Best,