- **CFX**
(*http://www.cfd-online.com/Forums/cfx/*)

- - **which is correct**
(*http://www.cfd-online.com/Forums/cfx/97010-correct.html*)

which is correctHi!
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)/ApThe 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^2where 0.55/k^0.5 = form coefficientboth 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 |

All times are GMT -4. The time now is 02:52. |