Hello, why am I getting these results? I solved analytically and got a temperature of -4°C on the side where no boundary condition applies, but the simulation only shows me the initial temperature I set.
Hey there,
You applied those boundary conditions to the same face, so that’s not going to work out very well. I copied your project and applied the surface heat flux to the other face. Note that heatflux has to be negative if heat is leaving the domain.
The result is exactly -4ºC as you predicted:
Hello and thank you for responding, but this is a problem proposed by the book heat and mass transfer (Cengel) and so it is, with both conditions on the same face. I think what you say is right, but it is rare that the book is wrong. If you have an answer to this one, let me know so that I can remove the doubt. (I’m just taking this course so I don’t know much). Thank you very much.
Greetings from me too 
The problem in the book is well-posed. But you could think that the amount of heat flux entering the domain (wall) from the one side is the same with the amount of heat flux exiting the wall from the opposite side. So, that’s why the simulation results of @Ricardopg are accurate. @Ricardopg correct me if I’m wrong Just trying to put myself into a problem-solving mode here!
Have a nice day!
hi there,
Yes, I think you are right but why does it work well with Ricardo’s approach and not with my approach? Because as you say, the heat flux coming into the domain is going to be the same as the heat flux going out, at least for this case.
As I can read here in the Simscale documentation resources, it is suggested not to apply both temperature and heat flux boundary conditions on the same group of entities so I bet the software’s solver is not designed to implement that: Temperature Fixed Value | Boundary Conditions | SimScale
Is that correct?
