- 學位論文
同心圓鰭片管上濕空氣對流冷凝熱傳之研究
Investigation of Convective Condensation Heat Transfer for Moist Air on a Concentric Circular Finned Tube
摘要
濕空氣的凝結現象在日常生活和工業領域中扮演著關鍵角色。在冷凝過程中，單相熱傳與相變熱傳會同時發生。同心圓鰭片管被認為是增強熱傳的有效元件。然而，對於濕空氣在同心圓鰭片管外冷凝過程中的潛熱和顯熱傳遞，尚未經過實驗研究。本研究旨在通過實驗使用同心圓鰭片管來增強濕空氣的冷凝效果。為了更好地理解增強機制，測量並分析了相對濕度範圍在75%至95%之間的潛熱和顯熱傳遞變化。此外，還對比了光滑管的性能，結果顯示同心圓鰭片管在強化濕空氣冷凝過程中尤為有效，尤其在潛熱傳遞方面表現突出。在相對濕度範圍為75%至95%時，同心圓鰭片管的單位時間冷凝水量和潛熱傳遞分別比光滑管高出69.09%至168.96%和68.9%至148%。此外，研究還測量了在溫濕度控制器中，不同傾角之不同濕空氣速度下同心圓鰭片管和光滑管的潛熱與顯熱傳遞，這些結果為設計用於濕空氣冷凝的同心圓鰭片管提供了寶貴的參考。
並列摘要
The phenomenon of moist air condensation plays a critical role in both everyday life and industrial applications. During the condensation process, single-phase heat transfer and phase-change heat transfer occur simultaneously. Concentric circular finned tubes are considered effective elements for enhancing heat transfer. However, the latent and sensible heat transfer during the condensation of moist air on the outside of Concentric circular finned tubes has not yet been experimentally studied. This study aims to enhance the condensation process of moist air by using Concentric circular finned tubes through experimentation. To better understand the enhancement mechanism, the variations in latent and sensible heat transfer within the relative humidity range of 75% to 95% were measured and analyzed. Additionally, a comparison was made with the performance of smooth tubes, and the results showed that Concentric circular finned tubes were particularly effective in enhancing moist air condensation, especially in terms of latent heat transfer. When the relative humidity ranged from 75% to 95%, the amount of condensate per unit time and the latent heat transfer of the Concentric circular finned tubes were 69.09% to 168.96% and 68.9% to 148% higher than those of the smooth tube, respectively. Moreover, the study also measured the latent and sensible heat transfer of Concentric circular finned tubes and smooth tubes at different moist air velocities and inclinations in the temperature and humidity controller. These results provide valuable reference data for designing Concentric circular finned tubes used in moist air condensation.