[esp-r] Re: Surface balance question

[Jon Hand]

A question about heat flows between a room and roof space...
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I'm trying to account the heat passing from the floor zone to the roof zone through the ceiling surface.
But I have no idea how I should read the balance for ceiling in floor_zone so that I can figure the heat going above (Trying to see the loss through that surface).

I attach the surface balances from res module.

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>From the attached report...

 Causal energy breakdown (Whrs) for roof_floor ( 1) in roof_space ( 2)
 Surface is opaque MLC, area= 69.75m^2 & connects to surface  7 in zone  1

                         Facing roof_space
                         Gain       Loss
 Conductive flux      35094.14        0.00
 Convective flux          9.69    -6598.47
 Longwave rad int      1294.16   -28791.25
 Heat stored           4608.62    -5616.91
 Plant                    0.00        0.00
 Totals               41006.61   -41006.63

Essentially this says that over the period of the simulation the
gains and losses balanced and the primary flux exchange between
the roof_floor surface and the room roof_space was via convection and
long wave radiant exchange.

>From the point-of-view of the surface it 'lost' energy to the roof_zone
in the amount of 6598W by convection with only a slight (9W) gain
by convection - and longwave exchange was 28791W loss and
a smaller gain 1294W.  This is consistent with the surface
being warmer than the roof space at almost all hours and that
the surface roof_floor was almost always warmer than the other
surfaces in the zone (so the longwave radiation is mostly
seen as a loss from the surface).

Heat storage takes into account the different state of the
heat embedded within the surface at the start and end
of the simulation.

Remember, the energy balance is a summation over time. You
might also want to plot or list out the individual flux paths
in the graphing facility or timestep listing so that you get
the pattern as it changes over time.  If you wanted to know
the heat transfer coefficients used you would have to turn
on the so-called trace facility and include the energy balance
details.

-Jon Hand