[eng_yasser_2020]

Hello every body,

I am working in a heat transfer problem using ANSYS-FLUENT

In my model, there are two stationary concentric cylinders. There is a gap between these two cylinders filled with a gas (not air).

The boundary conditions are:
- There is "Heat generated" in the inner cylinder = 29602 (W/m3)
- The ambient temperature is 29 (C) [it should be also a convection heat transfer coeffiecient but i can not get it (is unknown)]
That is all.

My problem is a 2-D heat transfer problem. I make a mesh file using ICEM CFD making a boundary condition in the outer surface of the inner cylinder, inner and outer surface of the outer cylinder as Wall.

In FLUENT i applied the Heat source boundary condition in the inner cylinder and FLUENT by defult make the walls (inner of outer cylinder and outer of the inner cylinder) as coupled and i apply the temperature of the outer wall, but after i make these, the problem not converged.

Is the meaning of the "Coupled", that the heat transfer from solid to fluid is by convection and radiation or not?

Can any one help Pls??

[vekh]

First - You are using C or K? (did you change units in fluent)
Second - is this a transient or steady state model?
Third - is there any other information or just "problem not converged"?

[eng_yasser_2020]

Thanks for replying "Rafal"

- I am using C, i have changed it in fluent
- It is a steady state model
- I want to add a convection boundary conditions for the outer wall of the inner pipe and for the inner wall for the outer pipe, but fluent by default make them coupled. I am not understanding the real meaning of the "Coupled" term.

Thanks

[alireza7246]

hi all, i have a square with heat generation rate inside that, i have three boundary conditions with constant temperature, but i dont have heat flux from one of walls, i want to simulate this problem in Fluent, could you please any one explain me??