Numerical Solution

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We see that we need to provide a convergence criterion for each PDE that is being solved. For this example, we will use the default values. Also make sure Plot box is checked. This will help you monitor how/whether the solution is proceeding to convergence. Click OK.

Next, we set the initial guess indicated in the flowchart. The initial guess can be entered using:

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For this example, we know the conditions at the inlet of the pipe (except for pressure which is set to zero gauge by default). Initialize the entire flowfield to the specified values at the inlet: First, select Standard Initialization, then under Compute from, select Inlet and click Initialize.

To prevent the computer from iterating indefinitely, we need to set an iterations limit.

Solution > Run Calculation 
Enter 500 for Number of Iterations and click Calculate. You will see a window message saying Calculating the solution... Wait for FLUENT to finish the calculation. You should see a residual plot on screen as the computation is being performed. It should look something like this:

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