topic Re: Heat transfer Simulation in boiler in CFD Forum

Heat transfer Simulation in boiler

Anonymous — Thu, 25 Apr 2013 04:03:51 GMT

Hi everybody,

I'm trying to simulate heat transfer in boiler by CFD (bellow image). However, it does not work. Temperature of all positionS is 800oC. I wonder what's wrong with models or boundary conditions? Please help me resolve it.

Thank all you so much.

Calculation file: http://www.mediafire.com/?p5gt77ar3em9cel

Result:

Re: Heat transfer Simulation in boiler

ilyas_drawbridge — Fri, 26 Apr 2013 07:50:00 GMT

Hi, it seems that your thermal BC might be inadequate. You only have 800C air coming into the domain, just that. If run till steady state, everything will ultimately be 800C. What I would do is apply a film coefficient BC at the outer walls of your parts to simulate some cooling due to convection of ambient air. Unless... you are expecting heat to transform into some other form of energy, then perhaps a -ve heat generation might work. What is the rubber doing there anyway?

Regards

Ilyas

Re: Heat transfer Simulation in boiler

apolo_vanderberg — Tue, 30 Apr 2013 18:18:31 GMT

Ilyas is correct here. To do a thermal model we will need at least 2 thermal boundary conditions.

You have an inlet temperature, we would need something else (Film Coefficient on exterior to represent how the model can lose heat to the surroundings that we do not have modeled; Neg Heat Generation to represent heat conversion of some sort; or a second flow domain that would have its own temperature inlet).

Apolo