Page 186 - ansys

ANSYS CFD

At convergence, the following should be satisfied:
1. All discrete conservation equations (momentum, energy, etc.) are obeyed in all cells
to a specified tolerance OR the solution no longer changes with subsequent iterations.
2. Overall mass, momentum, energy, and scalar balances are achieved.
3. Monitoring convergence using residual history:
4. Generally, a decrease in residuals by three orders of magnitude indicates at least
qualitative convergence. At this point, the major flow features should be established.
5. Scaled energy residual should decrease to 10-6 (for the pressure-based solver).
6. Scaled species residual may need to decrease to 10-5 to achieve species balance.
7. Monitoring quantitative convergence:
8. Monitor other relevant key variables/physical quantities for a confirmation.
9. Ensure that overall mass/heat/species conservation is satisfied.

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