Need Help with COMSOL - Seeking Guidance

[chirag.joshi]

hey guys...
can someone here, expert in COMSOL ,help me out ?
I am stuck in my work and seek some guidence..

Regards,

Chirag

 

[Vanechka]

...hi there, I think there are couple of us here who've been stuck with Comsol more than a few times ... usually with more or less happy endings, so just "bring it on" .

 

[chirag.joshi]

well...I am trying to simulate the adsorption cooling process with COMSOL.
This cycle has 4 parts i.e cooling, adsorption, heating ,desorption.I could simulate these processes one at a time easily. Now I want to model whole cycle in one comsol file. To begin with I am trying to couple cooling and adsorption process using integration point coupling variable. I have written one external script file. Ideally it should happen that when temperature at the specified location ( i.e surface of adsorber)reaches 397 K , the adsorption process should start i.e the adsorber starts to adsorb vapour and the vapour concentration increases with time. The simulation runs but the domain plot shows that there is immediate drop in surface concentration and eventually no adsorption effect is seen. I have modeled the boundary conditions as function of this coupling variable and checked the logic many time. If someone knows the probable mistake in this model, please revert back. I can send you the comsol files easily. Thanx a lot :)

 

[Vanechka]

As far as I can tell the way you've done it should work, however, there can be 'something' in how the steps couple and how one feeds others. How have you actually implemented the condition for starting the adsorption process (as a function of temperature & time ... or well, probably temperature) and is the adsorber given as a domain or directly as a bc? I was thinking whether some boundary or other sort of condition is leeching on the process too early (for example), doesn't take place at the appropriate time or temperature (like happens explicitly too early because of some expression that has an inherent time / temperature dependency etc.). I can take a look at the Comsol files if you wish as well (I'll PM you an email address for the files).

 

[chirag.joshi]

hey...thats so nice of you that you are eager to help !..
well, you can mail me ur email address...I will explain you the model in detail and send the corresponding COMSOL files as well..

 

[Yahyanm]

Hi there,
I'm trying to simulate bloob flow in an elastic tube using COMSOL and I need some help I'm using structure-fluid intraction in transient mode any tip will help