百葉式太陽集光器在建築日光照明的應用

Abstract

本論文提出一種日光導引系統，利用百葉式太陽集光器將日光重定向後導入建築物內部，可應用於日光輔助照明。本論文中提出的日光輔助照明系統主要包含三個部分：第一部分是利用單軸追跡之百葉式集光器將日光重定向到建築物內部天花板。集光器末端安置擴束器，以確保集光器輸出光線的方向能在預期的範圍內。第二部分在導引系統入口上方建立一可收折的短檐，其上具有微結構，能夠避免仰角較大之入射光經重定向後會以接近水平入射建築物而產生眩光。第三部分是透過室內天花板的光導管及擴散板，讓入射日光能更深入室內，並且經由混光後再向地板照射，提升室內整體的採光範圍及均齊度。本研究針對百葉式太陽集光器、短檐微結構、室內光導管、擴散板等部件進行優化，以提升整體系統光效率以及室內照明的均齊度。提出的百葉式太陽集光器模型經過優化後以550 nm單頻光光源進行模擬分析，結果顯示其對於入射光仰角容忍度可達 ±1.25°，方位角之容忍度則達 ±80° (維持95%效率以上)。最後將優化後的日光導引系統設置於摩洛哥的朝南建築，並同時考慮該地的直射光與漫射光進行模擬評估，結果顯示建築物內部的採光範圍可達室內7公尺，且全年之平均照度均齊度可達0.64，且最低均齊度大於0.56。This paper proposed a daylight guidance system to redirect sunlight into the building through a louvered solar collector for the application of daylight-assisted lighting. It includes three parts. The first part is to use the louvered collectors by means of single-axis tracing to redirect the sunlight to the ceiling of the room in buildings, and a beam expander was attached to the end of the louvered collector to ensure that the light emerging from it can fall within the desired directional range. The second part is to create a retractable short eaves with microstructures to prevent the light coming with a large elevation angle from being redirected into the building in a near-horizontal direction. The third part is to utilize a light duct and a diffuser plate to let the incident sunlight go further into the room and get mixed for the following irradiating the floor, which improves the overall lighting range and uniformity of the room.This study optimized components such as louvered solar collectors, short eaves microstructures, indoor light guides, and diffusers to improve the overall light efficiency of the system and the uniformity of indoor lighting. The proposed louvered solar concentrator model was optimized and simulated for a light source with an wavelength of 550 nm. The results show that its tolerance to the incident light elevation angle and the azimuth angle can reach ±1.25° and ±80°, respectively (maintained more than 95% efficiency). Finally, the optimized daylight guidance system model was assumed in a south-facing building in Morocco, and was evaluated in the simulation with considering the local conditions of both the direct light and diffused light. The average uniformity of illuminance can reach 0.64, and the minimum uniformity is greater than 0.56.