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Case 4: Periodic boundary condition was defined at the walls along the x-y plane, 1st order solver with convergence criteria of 10^-6 2nd order solver with convergence criteria of 10^-6 (solution obtained from the 1st order solver was used as an initial guess for the 2nd order solver).
Click here for detailed procedure of mesh generation in Gambit and problem definition in FLUENT.
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