Discussion Forum

Hi!

I am PhD student from Slovak technology University. I ran into a problem and searching for help. I am interested in CFD modeling, it is an embellishment of my experimental disertation thesys. I tried modeling frontal chromatography in matlab (linear driving force model), also COMSOL. The problem is, that competitive two-component Langmuir isotherm is used to describe adsorption therm. Experimentaly overshoot effect was obsserved. LDL model in MATLAB relibly described experimental data (also overshoot), but COMSOL did not, unfortunately... I tried to face this on my own, but failed, that's why I tried this forum... looking for help. Has anybody experience with overshoot effect (or frontal chromatography) modeling in comsol?

The model I made is based on "Transpor of Diluted Species in Porous Media". The result from COMSOL matches the experiment well, but overshoot effect is NOT seen from COMSOL (maximal concnteration of worse binding component coming out form column in liqiud phase is equal to feed concnetration, not possibly higher and that's the problem). I suppose that implicit solver needs to be configurated or PDE solver needs to be change by function or condition, but I am not such great/experienced COMSOL user, yet. Naturaly, it is possible that I made a misstake creating the model. However, all input parameters are the same as in MATLAB. Has anybody experience with problem like mine?

Please help me get through this trouble. I will be greatfull even for little help!!!

Patrik.