[Ahmed8]

Hi,

I'm fairly new to Ansys Fluent and I'm trying to simulate the flow around a 3D cylinder at Re = 300. I'm using transient, pressure-based solver All models are turned off except viscous model I'm using laminar model .

My domain dimensions are 20m from the inlet to the cylinder axis, 30m from the outlet to the cylinder axis, 20m from the bottom and top wall and 12m on the z direction. the cylinder has a diameter of 1m and a spanwise length of 12m.

My boundary conditions are velocity inlet at the inlet v = 0.00438 m/s, pressure-outlet at the outlet, no-slip boundary condition is imposed on the cylinder, for the top and bottom walls I specified a shear condition with shear stress at all component equal to 0. For the walls on spanwise (z-axis) direction I tried creatin a periodic boundary condition but I'm not sure if I did it right.

My Cd values seems to remain the same whether I create a periodic boundary condition or not and the average Cd is very high giving me a value of about 11.

Kindly please help me resolve this.