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 The information provided may be out of date.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.
Heat generation in concrete
Posted May 11, 2011, 9:54 a.m. EDT Heat Transfer & Phase Change Version 4.1 0 Replies
Please login with a confirmed email address before reporting spam
I am trying to model the heat generation in a concrete piece. To do so I have used the Heat Transfer model in COMSOL 4.1 and the Heat Source to input the heat generation as a general source.
The function I use to describe the heat generation is function of the chemical affinity (aff), which in turn is a function of the hydration degree evolution in time (xi(t)), of the form:
q = L * aff(xi) * exp(-Ea/RT);
aff(xi) = a * xi(t)^b * (1-xi(t))^c;
xi(t) = 1/m * (t-0.01);
where L, a, b, c, Ea/RT and m are constants
I have tried to describe both xi(t) and aff(xi) trough analytical functions in the "global definitions" section but when I call xi(t) while defyning aff(xi) it does not work.
I have also tried to only define xi(t) as an analytical function and then directly describe the aff(xi) in the Heat Source model, but I do not know if this is well done because the results are not good and it says that the unities are wrong.
Maybe I am doing something wrong and maybe there is an easier way to do this...
If anyone could help me I would be very greatfull.
Thank you and have a nice evening,
Ana Gaspar
Hello Ana Gaspar
Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.
If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.