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Buildings.Fluid.SolarCollectors.Controls.BaseClasses

Package of BaseClass models used to create the models in the Controls package

Information

This package contains base classes that are used in the Buildings.Fluid.SolarCollectors.Controls package.

Extends from Modelica.Icons.Package (Icon for standard packages).

Package Content

Name Description
Buildings.Fluid.SolarCollectors.Controls.BaseClasses.GCritCalc GCritCalc Model calculating the critical insolation level
Buildings.Fluid.SolarCollectors.Controls.BaseClasses.Examples Examples Package containing examples demonstrating the use of Controls.BaseClasses models

Buildings.Fluid.SolarCollectors.Controls.BaseClasses.GCritCalc Buildings.Fluid.SolarCollectors.Controls.BaseClasses.GCritCalc

Model calculating the critical insolation level

Buildings.Fluid.SolarCollectors.Controls.BaseClasses.GCritCalc

Information

This component calculates the solar radiation necessary for the fluid in the collector to gain heat. It is used in the model Buildings.Fluid.SolarCollectors.Controls.SolarPumpController.

The critical solar radiation level is calculated using Equation 6.8.2 in Duffie and Beckman (2006). It is

GTC=FRUL (TIn-TEnv) /(FR(τα))

where GTC is the critical solar radiation, FRUL is the heat loss coefficient, TIn is the inlet temperature, TEnv is the ambient temperature, and FR(τα) is the maximum efficiency.

References

J.A. Duffie and W.A. Beckman 2006, Solar Engineering of Thermal Processes (3rd Edition), John Wiley & Sons, Inc.

Extends from Modelica.Blocks.Icons.Block (Basic graphical layout of input/output block).

Parameters

TypeNameDefaultDescription
Realslope Slope from ratings data [W/(m2.K)]
Realy_intercept y_intercept from ratings data

Connectors

TypeNameDescription
input RealInputTInTemperature of water entering the collector [K]
output RealOutputG_TCCritical radiation level [W/m2]
input RealInputTEnvAmbient temperature at the collector [K]

Modelica definition

model GCritCalc "Model calculating the critical insolation level" extends Modelica.Blocks.Icons.Block; parameter Real slope(unit="W/(m2.K)") "Slope from ratings data"; parameter Real y_intercept "y_intercept from ratings data"; Modelica.Blocks.Interfaces.RealInput TIn(unit="K", displayUnit = "degC", quantity = "ThermodynamicTemperature") "Temperature of water entering the collector"; Modelica.Blocks.Interfaces.RealOutput G_TC(unit="W/m2", quantity = "RadiantEnergyFluenceRate") "Critical radiation level"; Modelica.Blocks.Interfaces.RealInput TEnv(unit="K", displayUnit = "degC", quantity = "ThermodynamicTemperature") "Ambient temperature at the collector"; equation G_TC = -slope * (TIn - TEnv) / y_intercept; end GCritCalc;

http://simulationresearch.lbl.gov/modelica