How to define a global variable as a function of local variables in comsol?
Answers
Answer:
Explanation:
am working on the simulation of a surface tension gradient by temperature gradient.
The relation between the temperature and the surface tension is represented in the variable called "Temperature derivative of the surface tension".
I am trying to add this variable as a function of T in COMSOL>Model builder>definitions>parameters.
However, the expression is marked red which means that there is an error, which I could not define.
And When I add a new variable at component>definition , the solver shows an error before starting the solution.
I will appreciate if you can help me with this problem.
Regards,
Ahmed
Answer:
I guess that the value of a parameter is fixed, and variable is varying (sic!) its value. A model has certain independent variables with which you can define new ones, also applied only in certain domains.
Example: I simulate diffusion in two domains that have variables c1 and c2. But if I want to make a plot across the entire geometry, I define that in domain 1, C = c1 and in domain 2, C = c2. Now I can plot variable C at once.