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.

problem using matlab functions with comsol

Yacine Ait Ouméziane

Please login with a confirmed email address before reporting spam

Hi all,

To present quickly my problem, I work on a 2D wall for which I study mass and heat transfers and I particularly interest myself on the phenomenon of hysteresis. To model this last one, I have to introduce the expression of the water content w : w=wR+(wS-wR)*(1+abs(alpha*R*Tref*log(HR)/(M*g))^eta)^(-m)
Tref, R, M and g are constants.
alpha, m, eta, wR and wS are 5 functions created under matlab which depend on 3 paramaters : HR the relative humidity which is a dependant variable, x and t.
Taken independently the 5 functions give me a correct answer for external solicitations after a comsol run. Moreover, the values taken by the expression of w and its derivative seem correct too. The main issue is that after the comsol run, HR, the relative humidity is not coherent at all.
Do you know from where it comes? Is it because my input and output dimensions are not the same? Is it a matlab problem or a comsol problem? If you want I can sent you my m- and mph-files the next time.

Best Regards

Yacine Ait Oumeziane

0 Replies Last Post Apr 5, 2011, 6:12 a.m. EDT
COMSOL Moderator

Hello Yacine Ait Ouméziane

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.

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.