Discussion Forum

Goodmorning,

I'm a new user and I have a problem in modelling a pipe full of water in forced convection inside a solid domain, heated by a source in some surfaces.

I am using the General heat transfer model and the weakly compressible Navier-Stokes model.

In particular my problem is about the boundary settings in the lateral surfaces of the pipe: I have used the "heat source / sink" condition with q0=0 and my "h" value between the pipe and the solid domain. The problem is that I don't know the external temperature (Tinf) because the pipe is inside a solid domain (a block) heated by two heat sources in two different surfaces; this means that Comsol should calculate the temperature on the pipe's external surface . How can I put the "pipe external surface temperature" (that vary in space and, if i will set a transient condition, through the time) as the Tinf value? In few words i want to simulate an imposed temperature on the surfaces, and a variable heat flux along the pipe's lenght.

Is there another way to model my problem?

I have also thought to insert some points near the pipe surface and to insert their temperature values as Tinf values but I don't know how to do this too.

My objective is to set an inlet temperature, an inlet and outlet pressure of the fluid and to know the temperature and velocity profile inside the pipe (and the outlet temperature).

Thank you!