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A larger varibility was shown in the parameters when compared between smmetry symmetry and wall boundary conditions, while little differences were observed in the energy dissipation contours with bare eyes. However, the variability are still within an acceptable ranging in terms of a varieity of other uncertainties in the practice of design and operation.
Convergence rate
The iteration steps needed for each cases at the three different convergence levels:
The above table suggests the case with wall boundary condition converges a lot faster
More comments
Also note that in all these cases the solutions were obtained by directly iterating towards e-6 with second order scheme, instead of the normal practice: iterating with first order to obtain an good initial guess and then with second order for more accurate values.
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