Forced convection between hot air and solid simulation in fluent
 

Hello Everyone,

I want to simulate the heat transfer between hot air surrounding a solid at ambient temperature. I want to plot the heat up process of the solid versus time until it gets to the same temperature of the fluid. So basically I am cooking a solid inside an oven you could say.

I am creating an interface between the solid and fluid. During setup, I am selecting transient, and in terms of boundary conditions, I am inserting an inlet velocity (5 m/s) and inlet temperature (400 K) which is higher than ambient. Other than that, I am leaving all the walls of the fluid domain as they are (I don't really care about those outside walls) and everything else is default. I am choosing the interface to be coupled.

As a result, I am getting a uniform temperature at the interface and even inside the solid, which is equal to the fluid temperature (400 K). I don't think any heat transfer is being done here. I am basically choosing a time step of 1s and 60 time steps.

I feel like I am missing something in terms of boundary conditions, or time steps. I would really appreciate any help on the matter.

Where you are defining solid temperature as ambient temperature? I think this is the only thing you are missing.

I am not actually. I am assuming it is ambient temperature by default. Are you saying that I should patch an inlet temperature of 300 K to the solid?

Of course yes, you are assuming but how software will assume? So you must patch.

Alright, so I did include an ambient temperature for the solid. I got a result, not the one I wanted but at least I got something. The temperature of the fluid got dissipated so instead of heating the part, the fluid was cooling down. How can I maintain this heating temperature (400 K) throughout the process until I get the part to that temperature? On a side note, the heating in reality is done at constant pressure of 90 psi. Should I input that value in both operating conditions and inlet boundary condition? Thank you!