[superlegit]

Hi,

Using buoyantSimpleFoam and the fvDOM model for radiation, I was trying to model a wall that received an external heat flux and external radiative heat flux. I applied the external wall heat flux BC for temperature:

type externalWallHeatFluxTemperature;
mode coefficient;
h 4.76;
Ta 306;
kappaMethod fluidThermo;
qr qr;

For radiative intensity I, I used the grey diffusive condition with an external incident radiation

type greyDiffusiveRadiation;
qRadExt 350;

The results were really weird, however. The wall temperature, which was initially at 306k, decreased significantly despite there being incident radiation. The results looked much better when I omitted the qr term from the temperature BC. The results also looked a lot better when I created a file for qr in the 0 folder and applied this BC meant for the viewFactor model

type greyDiffusiveRadiationViewFactor;
qro 350;

Nevertheless, I was wondering if this was the right way of modelling an external radiative flux. Also, if I leave the qr BC in but remove the qRadExt from the IDefault BC, it becomes as though there was no external radiative flux at all.

Thank you

[superlegit]

Also, I was wondering the difference between applying an external heat flux at a wall as opposed to applying an external radiative flux at a wall. I.e.,

Case 1:
For temperature,
type externalWallHeatFluxTemperature;
mode flux;
q 350;
kappaMethod fluidThermo;

Case 2:
(Using FvDOM)
For radiative intensity I,

type greyDiffusiveRadiation;
qRadExt 350;

The results I get are very different. For case 1, temperatures can increase by up to 50K. For case 2, the temperature does not increase by more than 3-4K