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 The information provided may be out of date.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.

Volume Fraction

Please login with a confirmed email address before reporting spam

Hi,
Is the Volume fraction In Fluid module based on the whole domain ? I have a geometry consists of 3 domains, two of them are fluids and the third one is solid. I think the definition of tpf.Vf1 is based on the volume of the whole geometry, Solid+liquid. I want to define the parameter based on the tpf.Vf1, but it gives me error , cause of the solid part.

2 Replies Last Post 18 janv. 2012, 23:58 UTC−5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 18 janv. 2012, 00:47 UTC−5
Hi

to get the volume of a domain: define an integration operator i.e intop1() and in your fomula (or define a variable) use

Vol =intop1(1)

--
Good luck
Ivar
Hi to get the volume of a domain: define an integration operator i.e intop1() and in your fomula (or define a variable) use Vol =intop1(1) -- Good luck Ivar

Nagi Elabbasi Facebook Reality Labs

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 18 janv. 2012, 23:58 UTC−5
I believe tpf.Vf1 is the volume fraction of fluid one in a two-phase fluid model. It is a field variable not a total quantity and gives the volume fraction at any point in the fluid domain. If you define a parameter based on this variable that parameter cannot be evaluated in the solid region since it does not have the “tpf” physics. If you want the total volume fraction you need to integrate as Ivar described.

Nagi Elabbasi
Veryst Engineering
I believe tpf.Vf1 is the volume fraction of fluid one in a two-phase fluid model. It is a field variable not a total quantity and gives the volume fraction at any point in the fluid domain. If you define a parameter based on this variable that parameter cannot be evaluated in the solid region since it does not have the “tpf” physics. If you want the total volume fraction you need to integrate as Ivar described. Nagi Elabbasi Veryst Engineering

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.