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Note that even when you solve for the physical velocity in Equation 7.19-31, the two resistance coefficients can still be derived using the superficial velocity as given in

Section 7.19.6. FLUENT assumes that the inputs for these resistance coefficients are based upon well-established

empirical correlations that are usually based on superficial velocity. Therefore, FLUENT automatically converts the inputs for the resistance coefficients into those that are compatible with the physical velocity formulation.

Note that the inlet mass flow is also calculated from the

superficial velocity. Therefore, for the same mass flow rate at the inlet and the same resistance coefficients, for either the

physical or superficial velocity formulation you should obtain the same pressure drop across the porous media zone.

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