sunrise hour angle is the negative of the sunset hour angle From this it

# Sunrise hour angle is the negative of the sunset hour

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s  20 SHADING - Solar plots Solar plots are a 2D representation of the sun paths over the sky dome. These paths are plotted for different periods of the year and are the projection of the sun orbits over the horizontal plane. Each solar plot is draw for a specific location (that is, for a certain latitude, φ ) and allows to assess the sun position for every hour of the day and for every day of the year, by means of the solar altitude angle, α s , and of the solar azimuth, γ s . Solar plots may be plotted in either polar or rectangular coordinate charts. Solar position plot of θ z and α s , versus γ s , for latitudes of ± 45°is shown in Figure. Lines of constant declination, δ , are labeled by dates of mean days of the months (see Table 1.6.1). Lines of constant hour angles, ω , are labeled by hours. (plots for latitudes from 0 to ± 70°are included in App endix H of Duffie & Beckman). SHADING - Type a) – Use of Solar plots (rectangular coordinate plot) The angular position of buildings, wingwalls, overhangs, or other obstructions can be entered on the same plot (the angular coordinates corresponding to altitude and azimuth angles of points on the obstruction - the object azimuth angle, γ o , and object altitude angle, α o ) can be calculated from trigonometric considerations and drawn on the plot). For obstructions such as buildings, the points selected must include corners or limits that define the extent of obstruction. It may or may not be necessary to select intermediate points to fully define shading. IDES-EDU 21 SHADING - Type a) – Use of Solar plots  #### You've reached the end of your free preview.

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