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ZoneSurfaceBus

A surface of a zone, zone side

FastSmoothBuildings.Interfaces.ZoneSurfaceBus, connector (source)

Purpose

A surface of a zone, zone side (one element of the array propsBus of Zones.PartialZone): the variables of SurfaceBus with the opposite causality, the weather wea being a WeatherBus through which the zone forwards its own.

VariableUnitSet byMeaning
con.TKzoneAir temperature of the zone
con.Q_flowWsurfaceConvective heat flow rate (flow variable)
rad.TKsurfaceTemperature of the room face of the surface
rad.Q_flowWzoneLong-wave and solar heat flow rate (flow variable)
Am2surfaceArea seen from the room
epsLw1surfaceLong-wave emissivity of the room side
absSol1surfaceDiffuse solar absorptance of the room side
tauSol1surfaceSolar transmittance back to the outside (windows)
isFloor1surface1 for a floor, 0 otherwise
QTraDir, QTraDifWsurfaceDirect and diffuse solar radiation transmitted into the room (windows)
hConInt, hConExtW/(m2K)zoneFixed interior and exterior convection coefficients, 0 for the natural convection and wind-dependent laws
weazoneWeather, forwarded by the zone

The heat flow rates are positive into the component that holds the port, so the convective and radiant heat gained by the surface is con.Q_flow + rad.Q_flow on the surface side, the opposite on the zone side. The zone shares the long-wave exchange through a radiant star with the weights epsLw*A, the transmitted diffuse radiation in proportion to absSol*A (with tauSol*A lost back to the outside), and the transmitted direct radiation on the floors first.

Use

Connect each element to the propsBus_a of one surface. The zone sets hConInt and hConExt of all its surfaces from its parameters of the same names.

Revisions

  • October 2026: moved from trano's FastModel.Interfaces.