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 The information provided may be out of date.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.
Large Parameter in Non-Linear Model
Posted 2011/12/20 7:39 GMT-5 Studies & Solvers Version 4.2a 3 Replies
Please login with a confirmed email address before reporting spam
Hi All,
I am trying to solve a stationary problem in Electrokinetics. I have a large parameter in my problem and the solver has been unable to solve for it.
I tried solving the problem with parametric sweep by setting the parameter to zero and gradually increasing its value.
I used a sweep of 400 steps from zero to 10% of the max value and Comsol stops solving when it reaches approximately 5% of the max value (i.e. halfway through).
Should I make the steps smaller? Any other suggestions? I also tried using a time-dependent solver, but that didn't help. In Direct should I change Mumps into Paradiso or Spooles?
Now lets say I was successful in such a sweep. Now I have another parameter I would like to scan but only with the max value of the first parameter. Can I save only the final sweep result? How do I use it as a new initial condition?
Now on another matter. I have another model that I am sweeping two separate ranges (lets say from [0,50], and [-50,0]). From what I know (I am still new at this). I need to sweep one (sweep a). Get my desired results and then sweep the other (sweep b) which overruns the results of sweep a. This is not very efficient, because if I want to see my previous results, I will need to solve again for sweep a.
How can I store the solution for sweep a and sweep b separately in the same file?
How do I control in to what data set/ solution the solution will be written into.
Thanks
I am trying to solve a stationary problem in Electrokinetics. I have a large parameter in my problem and the solver has been unable to solve for it.
I tried solving the problem with parametric sweep by setting the parameter to zero and gradually increasing its value.
I used a sweep of 400 steps from zero to 10% of the max value and Comsol stops solving when it reaches approximately 5% of the max value (i.e. halfway through).
Should I make the steps smaller? Any other suggestions? I also tried using a time-dependent solver, but that didn't help. In Direct should I change Mumps into Paradiso or Spooles?
Now lets say I was successful in such a sweep. Now I have another parameter I would like to scan but only with the max value of the first parameter. Can I save only the final sweep result? How do I use it as a new initial condition?
Now on another matter. I have another model that I am sweeping two separate ranges (lets say from [0,50], and [-50,0]). From what I know (I am still new at this). I need to sweep one (sweep a). Get my desired results and then sweep the other (sweep b) which overruns the results of sweep a. This is not very efficient, because if I want to see my previous results, I will need to solve again for sweep a.
How can I store the solution for sweep a and sweep b separately in the same file?
How do I control in to what data set/ solution the solution will be written into.
Thanks
3 Replies Last Post 2011/12/21 6:31 GMT-5