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 The information provided may be out of date.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.
Variable Definitions in Darcy's Law and Heat Transfer in 4.3
Posted 31.05.2012, 16:02 GMT-4 Heat Transfer & Phase Change, Porous Media Flow Version 3.5a, Version 4.3 1 Reply
Please login with a confirmed email address before reporting spam
Hi,
I'm just starting to work with COMSOL 4.3, and trying to run a model simulation that I used in 3.5a. The model is of an evaporator, and uses Darcy's Law and the Heat Transfer (Convection and Conduction) modules. One of the boundary conditions I set is the flow velocity of some liquid that evaporates off a surface into a channel. The velocity of the liquid would then be defined by:
U = (normal conductive heat flux/latent heat*density)
Or in Comsol 3.5a terms, it is set as a boundary condition in the Darcy's Law:
U = (ndflux_T_chcc/hfg/densityliq)
When I import this model into 4.3 and try to solve it, I was told that the ndflux_T_chcc does not exist. After looking at the documentation, it appears that this variable has been replaced by the equivalent 'ndflux'. But after changing this, I'm still having some problems. Should this be the fix, or is there something else I am doing wrong?
Thanks,
Nick
I'm just starting to work with COMSOL 4.3, and trying to run a model simulation that I used in 3.5a. The model is of an evaporator, and uses Darcy's Law and the Heat Transfer (Convection and Conduction) modules. One of the boundary conditions I set is the flow velocity of some liquid that evaporates off a surface into a channel. The velocity of the liquid would then be defined by:
U = (normal conductive heat flux/latent heat*density)
Or in Comsol 3.5a terms, it is set as a boundary condition in the Darcy's Law:
U = (ndflux_T_chcc/hfg/densityliq)
When I import this model into 4.3 and try to solve it, I was told that the ndflux_T_chcc does not exist. After looking at the documentation, it appears that this variable has been replaced by the equivalent 'ndflux'. But after changing this, I'm still having some problems. Should this be the fix, or is there something else I am doing wrong?
Thanks,
Nick
1 Reply Last Post 31.05.2012, 16:19 GMT-4
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
I have given up importing 3.5 into 4 and run them, you can import them to easier cut&past the forulas and see how it translates, but I can only suggest to rebuild the model from scratch, mainly because many variables have changed names, and in v4 there are more efficient ways to build your model
--
Good luck
Ivar
I have given up importing 3.5 into 4 and run them, you can import them to easier cut&past the forulas and see how it translates, but I can only suggest to rebuild the model from scratch, mainly because many variables have changed names, and in v4 there are more efficient ways to build your model
--
Good luck
Ivar