Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Select  ff1 from the Compute From drop-down list. FLUENT will update the reference values based on the boundary conditions at ff1. Click OK.

Iterate the Solution

Main Menu > Solve > Iterate...

You will have to input the time step size for iteration. Smaller time step means more accurate result but more computational time. We need to choose the balance between accuracy and computational power. 

Info
titleCalculating Time Step

The Strouhal number for flow past cylinder is roughly 0.183 as reported by Williamson (link).
In order to capture the shedding correctly, we should have at least 20 to 25 time steps in one shedding cycle. Let's use 25 for our case.
Sr = 0.183 = f*D/U
For our case, D = 2, U = 1
Therefore, shedding frequency f = 0.0915
Cycle time, t = 1/f = 10.9 sec
Therefore, Time Step Size = 10.9/25 = 0.436 sec

 
Go to Step 6: Analyze Results

...