Discussion Forum

hey guys,

first do i need to say, that i am using comsol 4.0 beta I and in that the model for PDE coefficient form.
so, there is the necessity to explain the following first, before you can answer my question:

i have a 2d model (a square 1.0x1.0) where an oscillation of the temperature (cos(t)) is given at the top, so this is a thermal problem. the rest of the bc's are actually irrelevant. if i treat the partial differential equation correctly an use a time integration mode, there is an oscillation of the temperature in the model that follows the boundary condition at the top, even if the model is saturated.
i drew a line from the top to the bottom at x=0.5 and y=0.0-1.0.

so, how am i able to plot that oscillation value (which shell be the maximum minus the minimum of the temperature within the period of the cosinus in the material) along the line for a special time.
so i don't want to plot u. furthermore to plot u(t)-u(t+pi) with the depth for a fixed time. maybe does that sound strange, but it need to be possible, cause i can plot every of those lines by themselves. but how do i combine these two lines in one...

moreover, if i write for the plot x-axis expression u it works. but making u(t) doesn't work, and that is actually what i need...

thank you so far, and if you have questions to my request... go ahead and ask me...

kind regards
manuel feuchter