Discussion Forum

Hi

I'm building a coupled model with comsol and phreeqc using matlab livelink.

What I'm doing is like this. First, run the model for 1 step (0.1 years) in comsol, and export the result data to the matlab. phreeqc uses the exported data from comsol and calculate the equalibrium state. After then, it returns the data to comsol as its new initial condition.

At the first time, I preferred to use mpheval to export data from comsol, and interpolation function to import data to comsol (I saved the phreeqc result as .txt file and used it in comsol). However, using the interpolation function was not stable, so now I'm trying to use mphgetu, mphxmeshinfo, and setU functions.

But I having a hard time with figuring out the physical meaning of solution vector returned by mphgetu. In my case, the mphgetu function returns 845x1 vector, which means the degrees of freedom of my model is 845 according to the manual.

However, the degrees of freedom obtained from mphxmeshinfo was 1430. I figured it out that the total degrees of freedom in my model is 1430, which includes 825 DOFs, and 605 internal DOFs.

Here is my question.

If I want to know what is the physical meaning of the solution vector returned by mphgetu, where should I look for? The mphxmeshinfo gave me the data with internal DOFs so I was not able to use it directly.

Thanks for reading!