blockBeamDepthInRoom

Depth of solar beam in the room

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

Information

This component computes the maximum distance at which a solar beam that enters the window hits the workplane. The distance is measured perpendicular to the wall.

The parameter azi is the azimuth of the window. For example, if the window faces south, set azi=Buildings.Types.Azimuth.S. The figure below explains the parameters.

Figure for beam depth parameters

For a definition of the parameters, see the User's Guide Buildings.BoundaryConditions.UsersGuide. The surface azimuth is defined in Buildings.Types.Azimuth.

The component requires as parameters the longitude, latitude and time zone. These can automatically be assigned by setting the parameter filNam to a weather data file, in which case these values are read from the weather data file.

Assumptions and approximations

The following assumptions and approximations are made:

If an overhang is present, then the corner of the overhang is the only object that casts a shade. In reality, for very shallow incidence angles, the top of the window frame may be sun exposed, but this model neglects any shade that is cast by the top of the window frame.
The overhang is assumed to have infinite length in the direction of the wall, as this allows neglecting any effects that the corner may have at shallow incidence angles.
The wall is vertical.

Parameters

Type	Name	Default	Description
Modelica.Units.SI.Angle	azi		Surface azimuth
Modelica.Units.SI.Length	hWorPla	0.75	Height of workplane above ground
Location
String	filNam	""	Name of weather data file (used to read longitude, latitude and time zone)
Modelica.Units.SI.Angle	lon	Buildings.BoundaryConditions.WeatherData.BaseClasses.getLongitudeTMY3(absFilNam)	Longitude
Modelica.Units.SI.Angle	lat	Buildings.BoundaryConditions.WeatherData.BaseClasses.getLatitudeTMY3(absFilNam)	Latitude
Modelica.Units.SI.Time	timZon	Buildings.BoundaryConditions.WeatherData.BaseClasses.getTimeZoneTMY3(absFilNam)	Time zone
Aperture
Modelica.Units.SI.Length	hApe		Upper height of aperature above ground
Modelica.Units.SI.Length	depApe	0.15	Depth of outer corner of aperture, measured from interior surface
Overhang
Modelica.Units.SI.Length	depOve	0	Depth of overhang, meausured from other exterior surface of aperature (set to 0 if no overhang)
Modelica.Units.SI.Length	gapOve	0	Gap between upper height of aperature and lower height of overhang (set to 0 if no overhang)

Connectors

Type	Name	Default	Description
Modelica.Blocks.Interfaces.RealOutput	y		Beam depth in room, measured perpendicular to window surface, at workplane height

Revisions

August 23, 2016, by Thierry S. Nouidui:
Propagated filNam.
April 21, 2016, by Michael Wetter:
Introduced absFilNam to avoid multiple calls to Buildings.BoundaryConditions.WeatherData.BaseClasses.getAbsolutePath. This is for Buildings, #506.
March 19, 2016, by Michael Wetter:
Set Evaluate=true for parameters lon, lat and timZon. This is required for OpenModelica to avoid a compilation error in Buildings.BoundaryConditions.SolarGeometry.Examples.ProjectedShadowLength.
November 14, 2015, by Michael Wetter:
First implementation.