[diaa]

Hi,
I am trying to simulate a hot-water boiler. I want to simulate the two physical properties or changes of fluid flow during heat transfer and obtain the output flow temperature given flow rate and the temperature of the burner tube which introduce heat to the water in the boiler.
I could make thermal only or fluid flow only simulation using other software but this is not satisfactory. Because in the thermal only transient simulation the water temperature increases from initial temperature, say 25 deg., to the tube of the burner temperature which is assumed to be 400 degrees. But this is not true because the water is not stand still and will flow out and inflow of cold water will flow in. So I concluded that Multiphysics, as Autodesk calls it, is the solution or coupling in other words. I need a tutorial link or any help.
Regards,
Engineer Diaa from Egypt

[stumpy]

This sounds like a standard CHT (Conjugate Heat Transfer) analysis. Search the Fluent doc/tutorials, there should be lots of info on CHT.

[diaa]

Dear stumpy,
Thanks for your reply! I found the following tutorial:
http://www.youtube.com/watch?v=1kYYaHRUHJY
Best regards,
Diaa

[diaa]

Dear All,
I have drawn the geometry in Autodesk Inventor as 4 parts and then collected them in one assembly.
The 4 parts are Boiler steel body, Water, Burner Tube fill (which is solid cylinder), and exhaust part in another tube (this is to add more heat by making use of the exhaust gases).
Then I reach the step of defining domains and get stuck in the interface domains. The interface is not generated automatically like in the tutorial.
In the tutorial when he created the new domain "Fluid domain" then renamed the default domain to "Solid domain" and changed its properties to define it as solid rather than liquid, when he did this, the interface solid fluid was created automatically and this does not happen in my case.
Is it because he used the fill command to generate the fluid part in the geometry previously but the fill command does not work with me so I imported it as part from inventor with the imported parts in the assembly file import, or is it because my geometry is not a simple pipe so maybe it is complex that the interface domain is not generated automatically.
So what should I do, should I add a named selection or group to include the interface surfaces for each part. For example the outer surface of the burner tube fill is in contact with the inner steel surface of the boiler burner tube, and the inner boiler steel surface is in contact with the outer surface of the water or the fluid part. Should I consider the burner exhaust and the burner flame which are the source of heat as air ideal gas with heat generation of "burner specification" Kilo Watt per hour or should I model it as a constrained surface temperature of say 400 degrees Celsius and the exhaust as a surface of temperature 200 deg. Celsius or this not professional but I did not reach this point yet.
Best regards,
Diaa