Nonuniform Woven Solar Shading Screens: Shading, Mechanical, and Daylighting Performance

Abstract

This study investigated the potential of using a nonuniform woven panel with nonuniform strips—thick sticks and thin battens—as an external solar shading screen that addressed daylighting, shading, and mechanical performance factors. The sustainable material, namely, bamboo, was used as the demonstration material for the screen. An on-site experiment and ANSYS simulation were carried out to investigate the basic solar optical performance and structural strength of the proposed screen, respectively. Then, a series of daylighting simulations were conducted to optimize the configuration of the screen. The results showed that the nonuniform woven solar shading screen reduced up to 80.3% of the solar radiation gain in a room during summer months while ensuring a relatively even distribution of useful daylight during the year. Moreover, the screen effectively reduced the negative impact of glare to a level below “imperceptible” and enabled a relatively clear view through the window and shading. Regarding the structural strength, the screen with a size smaller than or equal to 1 × 1 m withstood a wind load of 12 m/s. Furthermore, this study proposed two optimal configurations: a screen woven of square sticks and battens with a distance of 10 mm between them, and a screen woven of round sticks and battens with a distance of 8 mm between them. This study illustrated the superiority of the nonuniform woven solar shading screens, which supports a wider application of solar shading screens made of other materials with similar structures and reflectance values.

Numerical Study on Performance Optimization of an Energy-Saving Insulated Window

“…Other proposed sophisticated technologies include triple-glazing technology [17], external solar shading screens [18], doubled glazed window combined with light colored walls and roofs [19], natural ventilation [20], indoor thermal environments [21], Parallel Slat Transparent Insulation Material (PS-TIM) systems [22], window-opening behavior [23], impact of energy retrofits [24], translucent solar walls [25], active/passive ventilation walls [26], and windows with photovoltaic (PV) technology, aerogel glazing, or phase change material (PCM) glazing [27][28][29][30][31]. These methods are very efficient for satisfying building envelope thermal regulations, but they substantially deteriorate the view and reduce the occupants' thermal comfort.…”