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 The information provided may be out of date.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.

Finding ratio of two variables of two different domains

Please login with a confirmed email address before reporting spam

Hi every one
I have two domains . I have to find the ratio of two variables.
For example Variable 1 at domain 1 and variable 2 at domain 2.
Now I need the ratio of Variable 1 and variable 2. Further I need to update this ratio in domain 1 . How can I do this?

3 Replies Last Post 6 dic 2012, 05:04 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 6 dic 2012, 04:17 GMT-5
Hi

check the Data Set Join node in the help

--
Good luck
Ivar
Hi check the Data Set Join node in the help -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 6 dic 2012, 04:42 GMT-5
Hi Ivar
thank you. But I forget to tell you , these variables are integration of some other variables in the domain. For example. variable "x1' is for domain 1 and its integration over the domain is 'Y1' similarly for domain 2 . So in this case how can I find the ratio Y1/Y2.
Hi Ivar thank you. But I forget to tell you , these variables are integration of some other variables in the domain. For example. variable "x1' is for domain 1 and its integration over the domain is 'Y1' similarly for domain 2 . So in this case how can I find the ratio Y1/Y2.

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 6 dic 2012, 05:04 GMT-5
Hi

if I understand you can "join" data sets and then access them with a data1() and data(2) special operator (or perhaps you do not need to "join" them, check the "data1(" operator in the help), but in your case you can, from my understanding start to define in (each model if several) a variable for your integration and access the variable with the full name

if you have already a data set and solver case, and you add some integration in the Definition node, and variables, and these are NOT used in the solution, then you can do an "Solver Update solution" per study to get COSMOl to consider these new items. But if you want the solution to depend on some of these new variables, it's better to clear the solution and resolve from scratch

--
Good luck
Ivar
Hi if I understand you can "join" data sets and then access them with a data1() and data(2) special operator (or perhaps you do not need to "join" them, check the "data1(" operator in the help), but in your case you can, from my understanding start to define in (each model if several) a variable for your integration and access the variable with the full name if you have already a data set and solver case, and you add some integration in the Definition node, and variables, and these are NOT used in the solution, then you can do an "Solver Update solution" per study to get COSMOl to consider these new items. But if you want the solution to depend on some of these new variables, it's better to clear the solution and resolve from scratch -- Good luck Ivar

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.