[Alakbari]

I'm simulating a cooling process of water jet impingement on a hot plate. basically, initial temperature is 750 c , then its cool down due to the impingement of water.

problem description:

- constant horizontal hot plate with thickness and 0.2m fluid domain above the plate with interface between the plate and the fluid domain to capture the heat transfer.
- inlet velocity
- pressure outlet
- axisymmetric
- transient problem
- initial temperature 750 C

please, check the attachment photo to ease the description.


How can I find the Nusselt number and the heat transfer coefficient at the plate. however, each location of the plate has multiple temperature due to transient simulation.

thanks

[vinerm]

Is it a multiphase flow or single phase? And any reason for using interface between solid and fluid or by interface do you mean physical interface and not mesh interface?

Nusselt number is reported directly by Fluent. But you can also heat transfer coefficients based on wall temperature or wall function based equation.

[Alakbari]

the problem is multiphase flow, what do u mean by physical interface. what I did is coupled interface. Can you clarify how to calculate Nusselt number. or maybe can you share links that might help.

thanks

[vinerm]

Physical interface is what exists between fluid and solid in reality. In CFD terminology, interface is used to define non-conformal interfaces only. If the mesh is conformal, which is recommended until and unless there is a moving mesh being used, then it is called coupled wall.

For Nusselt number, you can just go to Reports > Surface Integrals > Wall Fluxes and report Nusselt Number. You can also plot its contour under Wall Fluxes.