不同空調運作方式對於公共空間熱舒適度之數值模擬分析

The Numerical Analysis of Thermal Comfort in Public Space by Different Operational Modes of Air Conditioners

徐偉展(Wei-zhan Xu)

指導教授 ： 洪勵吾

國立中央大學/工學院/機械工程學系/博士(2011年)

摘要

一般室內空調啟動後，即依據空調配置方式，對整個空間進行降溫，若考量空間人數與活動範圍，改變空調的運作模式，即可減省空調所需能源。本研究將利用計算流體力學的(CFD)方法，探討不同的空調運作方式如：十二進風口、單一進風口、雙進風口、調整進風口角度，在不同流速與溫度下，對於熱舒適度的影響。其中要使小區域空間達到熱舒適度，以單一出風口表現較佳。這是因為進風口彼此間的距離或總數增加，使室內流場中的渦流變多，因此提高冷熱空氣的混合，造成目標區域熱舒適度變差。此外在流速與溫度參數對於熱舒適度的影響，在溫度較低時，以調整流速影響較大；而進風口較高溫時，以調整溫度較大。另外以進風口與回風的流速、溫度進行空調能源使用評估，單一進風口最為節能，而若要維持相同的熱舒適度，在流場的初期空調以低溫、低流速較為節能；流場後期則提高溫度、流速較為節能。

關鍵字

熱舒適 ； CFD ； 空調

並列摘要

The cooling of space depends on the configuration of the air conditioners. Considering the numbers of people and their activities, we can change the mode of operation to reduce the energy consumption. In this study, the computational fluid dynamics (CFD) methods are used to analyze the differences of thermal comfort among operation modes, for examples: twelve inlets, single inlet, dual inlets and the angle of inlet at different velocities and temperature . The results show that single inlet system yiedlds better thermal comfort. This is because that the decreasing of distance between the air inlets or the increasing of number of air inlet generate lots of turbulence in the flow field which mix hot and cold air, and therefore cause the deterioration of thermal comfort. When the inlet temperature is low, flow velocity has more effect cmpared to other parameters. As the inlet temperature is relatively high, changing inlet temperature affect the thermal comfort mostly. The assessment of energy efficiency based on the temperature and velocity in inlet and outlet has been studied. At shows that the single inlet is the most efficient. If we want to maintain the same thermal comfort level but reduce the energy comsuption, the best way is to feed air with low temperature and low velocity in the beginning, and feed air with a higher temperature and velocity after the temperature reaching a certain value.

並列關鍵字

CFD ； Air Conditioner ； Thermal Comfort

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