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[EnergyPlus_Support] Re: baseboard : radiant convective :water

Hi Tooran,
In reallity the rate of heat transferable from the convective baseboard radiator is limited by :
1) The radiative surface area of the object
2) The temperature difference of the object surface (which is not uniform and highly dependant on massflow...which results in the dT across the inlet and outlet node.
3) The convection off the radiator.

I haven't looked at the model in depth. I can't remember if there was a field input for assigning the radiator size or area. I do remember the input field for the radiative convective transfer split. The model may correlate an adaptive convection coeff based on sized and or temp...you'll have to look into the engineering ref.

If this model does not work for you, the option exists to enter a surface object (of type wall) inside your zone to which you ascribe an internal source construction and a reverse surface with the matching construction. The 2 surfaces reference each other as boundry conditions, but the heat transfer will remain in both directions, I.e. you still radiate into the room. convection is calculated as for a wall surface by default so (due to the fins in the radiator) you may want to use a special convection coefficient to apply to the surface. There is an extra object to do this...I recently used it for an IRTsurface (look there in the io ref). This approach is probably more for advanced users...but I'm just highlighting an alternitive.

The first three points may help explain the dT you were asking about.

Hope that helps.



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