- 學位論文
冷卻樑板空調系統熱流場特性之數值模擬分析
Numerical Study of Thermal-Fluid Field of Chilled-Beam Air-conditioning System
摘要
冷卻樑板空調系統具有低能源消耗、節省空間、低噪音、維護保養容易，且可以提高室內舒適度等優點，在歐美已逐漸取代傳統空調系統成為市場主流，本文目的係要探討冷卻樑板空調系統熱流場特性及其對的人體舒適度。 本研究利用計算流體力學軟體模擬分析冷卻樑板空調系統的熱流場分佈，藉由熱流場可視化模擬，觀測模擬空間熱流場分佈特性，再利用紅外線熱攝像儀擷取其溫度場之分布與模擬結果進行驗證後，再以商務旅館房間及會議室空間模型模擬空間內之熱流場分佈特性。 研究結果顯示：1.冷卻樑板空調系統室內溫度分布均勻且平均風速0.5m/s，符合熱舒適要求室內均溫，平均風速低於1m/s；2.熱源位置及室內物品設備擺放位置對冷卻樑板空調系統室內熱流場有相當大的影響；3.設計冷卻樑板空調系統時需先行計算室內最高及平均熱負荷，依照熱負荷計算結果設計冷卻樑板空調系統，其中冷卻樑板冷卻能力需大於平均熱負荷，但小於最高熱負荷，不足之熱負荷由外氣空調箱協助冷卻，如此設計除可降低建置成本外，亦可達到節能效果。
並列摘要
With the advantages of low-energy consumption, space saving, low noise, easy maintenance, and indoor-comfort improvement, chilled-beam air-conditioning system is gradually replacing the traditional air conditioning systems in the area of Europe and the United States. The purpose of this paper is to explore the performance of the thermal-flow fields and the comfort of indoor climate that the chilled-beam air-conditioning system gives. This paper presents a computational fluid dynamics (CFD) simulation of the chilled-beam air-conditioning system. The visualization of air temperatures distribution and airflow patterns obtained from CFD calculation, which is validated by comparing with the thermographic images of temperatures distribution measured from an infrared camera, is used to analyze the performance of the chilled-beam air-conditioning system. In this study, two practical case studies - the air temperature and flow distributions in a hotel room and a conference room were discussed using the present CFD simulate method. Results indicate that: 1. using the chilled-beam air-conditioning system can obtain the uniform indoor air temperature distribution with the mean air speed less than 0.5m/s, satisfying the requirements of thermal comfort; 2. the position of heat sources and house furniture have a notable influence on the airflow pattern and air temperature distribution of the chilled-beam air-conditioning system; 3. to design a chilled-beam air-conditioning system, the room maximum and mean cooling loads should be found first. The cooling capacity of chilled-beam air-conditioning system must be greater than the average cooling load, but less than the maximum cooling load. The additional cooling load can be removed by the makeup air unit. The air-conditioning system built by the above design rule will reduce the cost of construction and save energy.