Interzone Exterior
Convection[LINK]
Why is my exterior convection coefficient value
0?
When two surfaces are linked as interzone surfaces, the
“exterior” side of these surfaces does not really exist.
EnergyPlus links the two surfaces by using the inside
temperature of surface A as the outside temperature of surface
B, and the reverse. For example:
Zone1WestWall has an outside boundary of Surface =
Zone2EastWall
Zone2EastWall has an outside boundary of Surface =
Zone1WestWall
Let’s say that at hour 2, the inside surface temperature of
Zone1WestWall is 19C, and the inside temperature of
Zone2EastWall is 22C. When the heat balance is calculated for
Zone1WestWall, its outside surface temperature will be set to
22C. Likewise, when the heat balance is calculated for
Zone2EastWall, its outside surface temperature will be set to
19C. So, for interzone surfaces, h ext does not apply. That is
why it is reported as zero.
Interzone Exterior Convection[LINK]
Why is my exterior convection coefficient value 0?
When two surfaces are linked as interzone surfaces, the “exterior” side of these surfaces does not really exist. EnergyPlus links the two surfaces by using the inside temperature of surface A as the outside temperature of surface B, and the reverse. For example:
Zone1WestWall has an outside boundary of Surface = Zone2EastWall
Zone2EastWall has an outside boundary of Surface = Zone1WestWall
Let’s say that at hour 2, the inside surface temperature of Zone1WestWall is 19C, and the inside temperature of Zone2EastWall is 22C. When the heat balance is calculated for Zone1WestWall, its outside surface temperature will be set to 22C. Likewise, when the heat balance is calculated for Zone2EastWall, its outside surface temperature will be set to 19C. So, for interzone surfaces, h ext does not apply. That is why it is reported as zero.
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