Subtask C2--New Daylight Algorithms

Available light

1.1 Solar geometry
1.11 Solar declination
1.12 Equation of time
1.13 True solar time and hour angle
1.14 Solar altitude and azimuth
1.15 Astronomical daylength
1.16 Shadow length
1.17 Ground shadow area of a rectangular building

1.2 Sunlight
1.21 Illuminance turbidity factor
1.22 Relative optical air mass
1.23 Extraterrestrial solar illuminance
1.24 Illuminance from direct sunlight

1.3 Skylight
1.31 Daylight availability: global & diffuse
1.32 Clear sky luminance and illuminance
1.33 Overcast sky luminance and illuminance
1.34 BRE average sky luminance and illuminance
1.35 Daylight coefficients and subdivision of the sky

1.4 External surfaces
1.41 Light reflected from the ground
1.42 Luminance of external obstructions
1.43 Specular reflection in external surfaces
1.44 Obstruction of the sky by trees

Daylight factor methods

2.1 Total
2.11 Daylight factor definition
2.12 Average daylight factor
2.13 Corrections to calculated daylight factor

2.2 Externally reflected component
2.21 Externally reflected component of the daylight factor

2.3 Sky component
2.31 Sky factor for unglazed vertical rectangular opening
2.32 Sky component for unglazed vertical rectangular opening
2.33 Sky component for unglazed horizontal rectangular opening
2.34 Directional transmittance of clear glass
2.35 Directional transmittance of non-clear glass
2.36 Diffuse transmittance of non-clear glass
2.37 Diffuse reflectance of non-clear glass

2.4 Internally reflected component
2.41 Average internally reflected component for vertical windows
2.42 Minimum internally reflected component for vertical windows
2.43 Average internally reflected component for rooflights

Finite area methods

3.1 Form factors
3.11 Configuration factor and form factor definitions
3.12 Form factor for identical parallel, opposite rectangles
3.13 Form factor for two perpendicular rectangles
3.14 Configuration factor for element parallel to rectangle
3.15 Configuration factor for element perpendicular to rectangle
3.16 Configuration factor and form factor with triangular subdivision

3.2 Radiosity method
3.21 General radiosity method using triangular patches (Currently Missing)
3.22 Test for hidden points with triangular subdivision
3.23 Daylight coefficient: direct component
3.24 Solution of inter-reflection equations

Ray tracing methods

4.1 Monte Carlo method
4.11 General procedure for Monte Carlo method
4.12 Random emission from point source and diffusing surface
4.13 Monte Carlo reflection at a surface


5.1 Geometrical framework
5.11 Axes and coordinates
5.12 Direction cosines of the normal to a plane
5.13 Angle between two vectors
5.14 Distance and direction between two points
5.15 Interception of a ray and a plane
5.16 Test whether a point lies on a plane
5.17 Sides, internal angles and area of a spherical triangle
5.18 Subdivision of a spherical triangle

5.2 Symbols and names of variables

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