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 February 7, 2012, 07:11 which is correct #1 Member   albert Join Date: Jan 2012 Posts: 31 Rep Power: 7 Sponsored Links Hi! i´m have some problems to set up the proper permability and resistance loss coefficient of my porous media. Actually i found different answers about how these coefficient are expressed, having different solutions with both of them. one is: You have to input a POROSITY, PERMEABILITY COEFFICIENT and RESISTANCE LOSS COEFFICIENT. The porosity is simply the % VOID of the region. The Permeability Coeff governs low speed viscous losses. If Erguns equation is to be adopted, this term can be calculated as: Kperm = [(Dp^2)*(epsilon^3)*(S^2)]/[150*(1-epsilon)^2] where: Dp = equivalent spherical diameter of particle = 6*(Volume of Particle/Surface Area of Particle) S = sphrecity (measure of how spherical) = ((pi^1/3)*(6Vp)^2/3)/Ap The Resistance Loss term governs inertia effects and can be calculated as: KLoss = 2[1.75*(1-epsilon)/(S*Dp*(epsilon^3)] and the other is an aproximation which says: Res.Loss COeff= 2*(0.55/k^0.5)* porosity^2 where 0.55/k^0.5 = form coefficient both ways have as a result very different values of Kperm and Kloss. could someone help me? has each Kpermeability necesarily an associated and unique Rloss? thank you

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