Learning Forum

[Karthik Sasihithlu]

I am trying to simulate a simple model consisting of a substrate(alumimium) on which a paint is applied.
for the boundary conditions,
Just to start with a simple problem, I have applied convection on both top and bottom surface of the body with a heat transfer coefficient of 5 and free stream temperature of 313K. I want the body to loose the heat gained via convection to be lost by radiation emitted from the paint.
I want to set up an wavelength dependent emissivity for our paint, for which i have defined 3 bands .

but there are a quite a few abnormalities which i observe not able get any reliable result. in thewhen there is no source of radiation defined how is there such a huge amount of incident radiation where as i haven't specified any external source of radiation on the surface. system and i am 

neglegible effect in temperature whereas from our hand calculations reveal atleast 10°C drop in temperature has to be observed with the above dataHere is the case file i am attaching, please look in to the problem and let me know the solution as soon as possible.

All this looks very confusing as the film on the substrate is the only body participating in the simulation

[C N]

Hello Karthik,

I am attaching this AIC course link on convective and radiative cooling . Please follow this for best practices. check your boundary conditions accordingly.

Convection and Radiative Simulation Example | Ansys Courses

I hope this helps you.

Thanks,

Chaitanya Natraj