Abstract Shortwave solar irradiance through building windows may have significant impacts on indoor thermal comfort, especially in near-window zones. Such effects change with intensity and spectral variations of the solar irradiance incident on building windows, which is related to the day of the year, time of day, orientation and dimension of the window, and atmospheric conditions. To assess the effects on thermal comfort, we derived a variable - mean radiant temperature delta based on a proposed spectrally-resolved method to represent the quantity of shortwave solar irradiance incident on occupants and be incorporated into PMV (predicted mean votes)-based thermal comfort models. By characterizing the variations of the calculated PMV values under different solar conditions, the influencing factors to indoor thermal comfort by shortwave solar irradiance were obtained and analyzed. Last, upon a series of parametric settings and numerical analysis, simplified statistical regression models were also established to directly predict spectrally-resolved mean radiant temperature delta and PMV values. This could be convenient and extensively to estimate the solar effects on indoor thermal comfort within the near-window zones.
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Steps in Designing an Indicator for Assessing Window’s Effect on Indoor Thermal Comfort
The effects of solar radiation play an important role in human thermal comfort, especially within the near-window zones. In the incorporation of the solar effect into the thermal comfort model, the comprehensive solar-optical characteristics of windows have to be taken into account, especially when it came to a largely variant or unbalanced spectral distribution of a building window. In this work, we examined the thermal effects varying with different spectral characteristics of glazing systems and also preliminarily proposed a new indicator “thermal effect index (TEI)” that can be used to estimate the impact levels of window systems on indoor users’ thermal comfort in near-window zones. TEI could be used as a benchmark for assessing a window system’s potential impacts on indoor users’ thermal comfort, especially when direct sunlight is enabled in a space.
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- Award ID(s):
- 2001207
- NSF-PAR ID:
- 10425047
- Date Published:
- Journal Name:
- Proceedings of the 5th International Conference on Building Energy and Environment
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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