Dear Hayder Allami

Could you attach a photo of your counters or streamlines?

Is there the mesh inside the baffles?

If so, then it should have happened.

The mesh must be absent inside the baffles. Or, on the baffles surfaces the boundary condition must be set - a wall.

Regards

Dear Andrii Rogovyi

I have attached what u have required.

yes there are mesh. and I have set the wall of baffles as wall , but still as you can see in the attached pictures

cheers

You probably have two geometry objects in the Meshing. You can suppress body of baffles and do not generate mesh on it.

But if you have only one geometry object in the Meshing that means your geometry is bad. Because your baffles unite with the pipe.