Menu

Discussion Forum

New Discussion
查找

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Question about Permeability Units

Posted 2015年9月25日 GMT-4 09:52 Microfluidics Version 4.2a 2 Replies

Elizabeth Walker
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hello,

My model contains a porous membrane which I am trying to characterize (permeability and porosity) with physiological values. When characterizing the porous membrane, COMSOL asks for permeability units of m^2; however, in all of the papers that I've looked at to find physiological values, their units of permeability have been cm/s. I've found some other information on converting from hydraulic conductivity (cm/s) to permeability (m^2) but I'm not sure how relevant it is. Does anybody have experience with trying to convert these units and if so, what did you do?

Thank you.
2 Replies Last Post 2016年12月30日 GMT-5 16:08
COMSOL Moderator

Hello Elizabeth Walker

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.

Prasoon Awasthi
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 8 years ago 2016年12月30日 GMT-5 13:29
Hi

I saw the Brinkman equation, in which 'k' is the permeability tensor with m^2 unit. If you search permeability tensor in Google, you will get 'Permeability (earth sciences)' wikipedia link, in this m^2 unit is given.
But I am also not cleared about how to convert m/s or cm/s unit to m^2 unit, because both are the permeability unit and both are contradicting also.
Hi I saw the Brinkman equation, in which 'k' is the permeability tensor with m^2 unit. If you search permeability tensor in Google, you will get 'Permeability (earth sciences)' wikipedia link, in this m^2 unit is given. But I am also not cleared about how to convert m/s or cm/s unit to m^2 unit, because both are the permeability unit and both are contradicting also.
Suresh Seetharam
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 8 years ago 2016年12月30日 GMT-5 16:08
Hi,


Often permeability and hydraulic conductivity are mixed up.

The unit of intrinsic permeability is m^2 and that of conductivity is m/s.

To convert m^2 into m/s you multiply permeability (m^2) with rho*g_const/mu, where rho (kg/m^3) is liquid density, g_const (m/s^2)is the internal variable within comsol for gravity and mu (kg/m/s) is the dynamic viscosity.


Suresh
Hi, Often permeability and hydraulic conductivity are mixed up. The unit of intrinsic permeability is m^2 and that of conductivity is m/s. To convert m^2 into m/s you multiply permeability (m^2) with rho*g_const/mu, where rho (kg/m^3) is liquid density, g_const (m/s^2)is the internal variable within comsol for gravity and mu (kg/m/s) is the dynamic viscosity. Suresh

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content