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#1 |
New Member
Timothy
Join Date: Feb 2023
Posts: 4
Rep Power: 3 ![]() |
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 |
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#2 |
New Member
Timothy
Join Date: Feb 2023
Posts: 4
Rep Power: 3 ![]() |
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 |
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Tags |
buoyantsimplefoam, radiation fvdom, radiative heat flux |
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