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Sky Series #

A sky series contains both cumulative and over time data about the energy emitted from the sky, at a location during a specified time period. It is used for both radiation and daylight related analyses, usually in combination with a shading mask. See the sky instance for further description about how the sunlight is represented in the sky.

Series Data#

The point in time data in the sky series covers each time step in the specified time pattern. This data is used for analyses that measure conditions over time, like useful daylight illuminance. Each patch for each time step contains the diffuse, direct and total amount of irradiance \(W/m^2\) and illuminance \(cd/m^2\) emitted at the specific point in time.

Cumulative Radiation Sky Cumulative Radiation Sky
The point in time diffuse, direct and total irradiance in a sky series covering the full day for the 21st of March in London.

Cumulative Data#

The cumulative data in the sky series is used for analyses that measure total recipience over time, like the cumulative radiation analysis. Each patch contains the diffuse, direct and total amount of irradiation \(Wh/m^2\) and cumulative illuminance \(cd.h/m^2\) emitted over the time span in the time pattern.

Cumulative Radiation Sky
The cumulative diffuse, direct and total irradiation in a sky series for a whole year in London.

Create Sky Series#

Weather#

The weather describes the location specific conditions that will be used to determine the sky conditions. The weather data is measured on an hourly interval and will be interpolated for sub hourly time steps.

Hemisphere#

The hemisphere decides the subdivision of the sky dome and thereby the amount of patches that should be used to describe the sky conditions. More patches produce a higher resolution and
thereby a more accurate interpretation of the sky but will also lead to longer analysis times.

Time Pattern#

The time pattern specifies the points in time that will be sampled in the sky series. The amount of time steps in the time pattern will decide the amount of skies sampled per hour and thereby greatly affect the time based resolution, especially for the directional factor.

Time Steps directional light
The directional irradiation for two cumulative skies. They are based on the same weather data, cover the same total time span and have the same total amount of irradiation but different time step settings. The left sky has 6 time steps per hour while the right one has 1 time step per hour.