[guidolg]

Hi,

I am trying to model the flow past a golf ball and compare it to a round ball.

My golf ball has a diameter of 42.6 mm, the depth of the dimple is 1 mm.

I set a Re number of 150.000:

Velocity= 53 m/s.
Density = 1.204 kg/m3.
Dynamic viscosity = 1.8205e-5 kg/m*s.
D=0.0426 m.

The solvers that I am using are:

- Three dimensional
- Segregated flow.
- Constant density.
- Turbulent: LES.
- Implicit unsteady.

I have uploaded an image of my mesh.

I have run the simulations and the result I got is that drag force over the round ball is lower than the one over the ball with dimples and I should get the opposite result.

Could you please comment on the settings I am using? Do you think that the mesh and the models I am using are proper for modelling this problem?

Now I am using All y+ wall treatment. Should I use low y+ wall treatment?

Thanks in advance.

Guido.

P.S.: I am trying to replicate the conditions used in this paper https://www.researchgate.net/publica...ning_Golf_Ball

[JBeilke]

There are already many discussions about this topic on cfd online.

The picture doesn't show anything usefull :-(