Permeability in porous media

- July 16, 2019 at 9:04 pm
  
  ketakijoshi
  Subscriber
  
  I am reading Fluent User's guide for porous media calculations. In formulations used, notations: α and K are both used for permeability. It also says that K is function of 1-γ, γ is porosity. Can you please tell if both these are same permeability. Or is K hydraulic permeability. I am not able to relate these formulations to standard formula as I am confused about these permeability.
- July 17, 2019 at 6:22 am
  
  DrAmine
  Ansys Employee
  
  Fluent refers to "alpha" as being the permeability. When it comes to multiphase porous media we refer the permeability as the intrinsic or absolute permeability (K) due to the porous media itself which needs to be weighted by the "relative" permeability which is due to the presence of the phases.
  
  If you are single phase forget about K.
- July 17, 2019 at 1:12 pm
  
  ketakijoshi
  Subscriber
  
  K is also used physical velocity formulation for single phase flow. Then what is this k?
  
  is K here also absolute permeability?
  
  Input in porous media condition : viscous resistance(inverse absolute permeability). This value should be alpha. Is it correct?
- July 17, 2019 at 2:57 pm
  
  DrAmine
  Ansys Employee
  
  Absolute permeability. Fluent understands your input for resistance as built on superficial velocity for that reason I am always referring to "alpha".
  
  If you put in the superficial approach the true velocity instead you then end up with the equation you shared.
  
  Next time refer to the version you are using + Eq. Nr to avoid misunderstanding