Superficial velocity mixture average

This relation can be solved for the superficial velocity, provided that the density is known from a appropriate EOS. For gas mixtures the ideal gas law is often used, thus the changes in composition is taken into account through the average molecular mass of the mixture. Moreover, the continuity equation can be integrated from the inlet z = 0 to any level z = z, to show that the mass flux is constant in the tube pv ) z = (/W ) in = Constant kg/m s). In particular, this integral relationship is frequently used to simplify the models, calculating the convective/advective flux terms from the known inlet values. 

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