室內空調進排氣口配置熱舒適性探討

A Study on the Arrangement of Air Conditioning Inlet/Outlet and the Thermal Comfort

就生理與能量傳輸觀點而言，欲使人體的冷熱感覺達到舒適程度，人體與外界的熱量傳輸關係必須達到平衡。當此熱量傳輸關係無法達到平衡時，即會形成人體的熱負荷，造成對冷熱感覺的不舒適感。而人體與環境的熱量傳輸關係又與風溫、風速、濕度、輻射溫度等環境因素有關以及衣著量、活動量等個人因素相關。PMV （Predicted Mean Vote）熱舒適指標即根據熱負荷與人體主觀感覺之間的關係而建立，可自環境與個人因素量化推估人體對環境的冷熱舒適感。本研究使用二維渦流流場模式計算在不同空調進排氣口配置形態下室內溫度與風速的分佈。在其他因素固定的條件下，可根據風速與風溫計算室內人員活動區域各點之 PMV 值。本研究先分別以實驗室量測與模擬計算求得流場中的風速與風溫，據以計算 PMV 值，做為驗證比較依據；其次再以經驗證的流場模式探討各種空調進排氣口配置對 PMV 值的影響。根據 PMV 指標量化評估結果，可瞭解在不同進排氣口配置形態與位置變動狀況下對室內熱舒適性的影響，並有助於達成進排氣口配置之最佳化設計。

From the viewpoint of physiology and heat transfer, a heat balance between the human body and its surrounding environment is a necessary condition to achieve thermal comfort. An unbalance will generate a thermal load to the human body, and then uncomfortable feeling to the environment. Heat transfer of the human body depends on several factors such as temperature and humidity of the air, wind speed, mean radiation temperature, clothing, and the human activity. The PMV (Predicted Mean Vote) index has been established based on the relationship between thermal load and subjective feeling. This index allows us to evaluate thermal comfort in terms of the factors mentioned above. This study employed a model of two-dimensional vorticity to calculate the air temperature and wind speed in an indoor environment under a variety of air-conditioning inlet/outlet arrangements. While the other parameters are given, the PMV values in the human activity zone can be obtained by calculated air temperature and wind speed. The model was first validated by comparing the PMV values based on calculated air temperature and wind speed with those based on experimental measurement. Then the effect of inlet/outlet arrangements was evaluated quantitatively in term of an over-all PMV-related index. This enabled us to understand the impact of air-conditioning inlet/outlet arrangements to the indoor thermal comfort, and suggest an optimal arrangement.