blockNightSkyTemp

Apparent night sky temperature
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Extends from Modelica.Blocks.Interfaces.SISO (Single Input Single Output continuous control block).

Information

The model also requires the apparent temperature of the night sky to compute the radiation of the structure to the sky during the night. The night sky temperature depends on the ambient temperature, the humidity, and the cloud cover. All three are retrieved from huge data tables stored on an external binary file.

References:

  1. Berdahl, P. and R. Fromberg (1982), "The Thermal Radiance of Clear Skies," Solar Energy, 29(4), pp. 299-314.
  2. Kimbal, B.A. and S.B. Idso (1982), "A Model of Thermal Radiation from Partly Claudy Skies," Water Resources Research, 18(4), pp. 931-936.

Parameters

TypeNameDefaultDescription
Realm0.556Multiplicative factor for conversion of temperature from Fahrenheit to Centigrade
Modelica.SIunits.CelsiusTemperaturea-17.78Additive factor for conversion of temperature from Fahrenheit to Centigrade
Modelica.SIunits.TemperatureT0-Modelica.Constants.T_zeroConversion between Centigrade and Kelvin

Connectors

TypeNameDefaultDescription
RealInputu (from SISO)Connector of Real input signal
RealOutputy (from SISO)Connector of Real output signal

Components

TypeNameDefaultDescription
Modelica.SIunits.CelsiusTemperaturetdpWet bulb (dew point) temperature
RealccfDiffuse radiation
Realeps1Emissivity of clear sky
Realeps2Emissivity of sky with cloud cover
Modelica.Blocks.Math.GainCelsiusConversion2
Modelica.Blocks.Math.GainCelsiusConversion1
Modelica.Blocks.Sources.ConstantOffset
Modelica.Blocks.Math.AddAdd1
Modelica.Blocks.Math.AddAdd2
Modelica.Blocks.Math.AddAdd3
Modelica.Blocks.Sources.ConstantKelvinConversion
Modelica.Blocks.Math.ProductProduct1
Modelica.Blocks.Tables.CombiTable1DsTempTable
Modelica.Blocks.Tables.CombiTable1DsWetTable
Modelica.Blocks.Tables.CombiTable1DsCloudTable