Buildings.ThermalZones.ReducedOrder.EquivalentAirTemperature

Package with models for equivalent air temperatures according to VDI 6007 Part 1

Information

This package contains models to calculate an equivalent air temperature taking into account short-wave and long-wave radiation on exterior surfaces.

Extends from Modelica.Icons.VariantsPackage (Icon for package containing variants).

Package Content

Name	Description
UsersGuide	User's Guide
VDI6007	Equivalent air temperature as defined in VDI 6007 Part 1
VDI6007WithWindow	Equivalent air temperature as defined in VDI 6007 Part 1 with modifications
BaseClasses	Package with base classes for the equivalent air temperature

Buildings.ThermalZones.ReducedOrder.EquivalentAirTemperature.VDI6007

Equivalent air temperature as defined in VDI 6007 Part 1

Buildings.ThermalZones.ReducedOrder.EquivalentAirTemperature.VDI6007

Information

VDI6007 is a strict implementation of the calculations defined in VDI 6007 Part 1. The sum of all weightfactors should be one.

Extends from BaseClasses.PartialVDI6007 (Partial model for equivalent air temperature as defined in VDI 6007 Part 1).

Parameters

Type	Name	Default	Description
Emissivity	aExt		Coefficient of absorption of exterior walls (outdoor) [1]
Integer	n		Number of orientations (without ground)
Real	wfWall[n]		Weight factors of the walls [1]
Real	wfWin[n]		Weight factors of the windows [1]
Real	wfGro		Weight factor of the ground (0 if not considered) [1]
Temperature	TGro		Temperature of the ground in contact with floor plate [K]
CoefficientOfHeatTransfer	alphaWallOut		Exterior walls convective coefficient of heat transfer (outdoor) [W/(m2.K)]
CoefficientOfHeatTransfer	alphaRad		Coefficient of heat transfer for linearized radiation [W/(m2.K)]
Boolean	withLongwave	true	Set to true to include longwave radiation exchange

Connectors

Type	Name	Description
input RealInput	HSol[n]	Solar radiation per unit area [W/m2]
input RealInput	TBlaSky	Black-body sky temperature [K]
input RealInput	TDryBul	Dry bulb temperature [K]
output RealOutput	TEqAir	Equivalent air temperature [K]
input RealInput	sunblind[n]	Opening factor of sunblinds for each direction (0 - open to 1 - closed) [1]

Modelica definition

model VDI6007 "Equivalent air temperature as defined in VDI 6007 Part 1" extends BaseClasses.PartialVDI6007; initial equation assert(noEvent(abs(sum(wfWall) + sum(wfWin) + wfGro - 1) < 0.1), "The sum of the weighting factors (walls,windows and ground) is <0.9 or >1.1. Normally, the sum should be 1.", level=AssertionLevel.warning); equation delTEqLWWin=delTEqLW; TEqAir = TEqWall*wfWall + TEqWin*wfWin + TGro*wfGro; end VDI6007;

Buildings.ThermalZones.ReducedOrder.EquivalentAirTemperature.VDI6007WithWindow

Equivalent air temperature as defined in VDI 6007 Part 1 with modifications

Buildings.ThermalZones.ReducedOrder.EquivalentAirTemperature.VDI6007WithWindow

Information

This model is a variant of the calculations defined in VDI 6007 Part 1. It adds a second equivalent air temperature for windows in case heat transfer through windows and exterior walls is handled separately in the Reduced Order Model. The sum of all weightfactors for windows should be one as well as the sum for all wall elements.

Extends from BaseClasses.PartialVDI6007 (Partial model for equivalent air temperature as defined in VDI 6007 Part 1).

Parameters

Type	Name	Default	Description
Emissivity	aExt		Coefficient of absorption of exterior walls (outdoor) [1]
Integer	n		Number of orientations (without ground)
Real	wfWall[n]		Weight factors of the walls [1]
Real	wfWin[n]		Weight factors of the windows [1]
Real	wfGro		Weight factor of the ground (0 if not considered) [1]
Temperature	TGro		Temperature of the ground in contact with floor plate [K]
CoefficientOfHeatTransfer	alphaWallOut		Exterior walls convective coefficient of heat transfer (outdoor) [W/(m2.K)]
CoefficientOfHeatTransfer	alphaRad		Coefficient of heat transfer for linearized radiation [W/(m2.K)]
Boolean	withLongwave	true	Set to true to include longwave radiation exchange
CoefficientOfHeatTransfer	alphaWinOut		Windows' convective coefficient of heat transfer (outdoor) [W/(m2.K)]

Connectors

Type	Name	Description
input RealInput	HSol[n]	Solar radiation per unit area [W/m2]
input RealInput	TBlaSky	Black-body sky temperature [K]
input RealInput	TDryBul	Dry bulb temperature [K]
output RealOutput	TEqAir	Equivalent air temperature [K]
input RealInput	sunblind[n]	Opening factor of sunblinds for each direction (0 - open to 1 - closed) [1]
output RealOutput	TEqAirWin	Equivalent air temperature for windows (no short-wave radiation) [K]

Modelica definition

model VDI6007WithWindow "Equivalent air temperature as defined in VDI 6007 Part 1 with modifications" extends BaseClasses.PartialVDI6007; parameter Modelica.SIunits.CoefficientOfHeatTransfer alphaWinOut "Windows' convective coefficient of heat transfer (outdoor)"; Modelica.Blocks.Interfaces.RealOutput TEqAirWin(final unit="K") "Equivalent air temperature for windows (no short-wave radiation)"; initial equation assert(noEvent(abs(sum(wfWall) + wfGro - 1) < 0.1), "The sum of the weightfactors (walls and ground) is <0.9 or >1.1. Normally, the sum should be 1.", level=AssertionLevel.warning); assert(noEvent(abs(sum(wfWin) - 1) < 0.1), "The sum of the weightfactors (windows) is <0.9 or >1.1. Normally, the sum should be 1.", level=AssertionLevel.warning); equation delTEqLWWin=(TBlaSky-TDryBul)*alphaRad/(alphaRad+alphaWinOut); TEqAir = TEqWall*wfWall + TGro*wfGro; TEqAirWin = TEqWin*wfWin; end VDI6007WithWindow;