碩士 / 國立勤益科技大學 / 冷凍空調系 / 98 / The two row fin and tube heat exchanger with continuous fin and stacked split fin are investigated numerically. The split heat exchangers are stacked with single row heat exchanger under different split span and the fin is arrayed in-line and staggered. The plain plate fin and enhanced slit fin are used with two fin pitches 1.21 mm and 2.5 mm, the air velocity is increased from 0.25 m/s to 3.5 m/s to see the fin split effect upon heat transfer rate and pressure drop of the heat exchangers. The heat transfer among fin and bare tube in the 1st and 2nd row are also analyzed in the results.
The results show that the stacked split fin and tube heat exchanger has little difference with the continuous fin heat exchanger in the heat transfer and pressure drop when the split span is smaller than 1.2 mm. In all heat exchanger combinations between 1st and 2nd row, the 1st row in the 2.5 mm fin pitch slit fin stacked with the 2nd row in the 1.25 mm fin pitch plain plate fin has the best j/f value in the studied air velocity range. The first row heat exchanger accounts for the most heat transfer rate of the heat exchanger in the low air velocity, and the second row has obvious heat transfer contribution when the air velocity is high. This study provides the important design information about the stacked fin and tube heat exchanger.
| Identifer | oai:union.ndltd.org:TW/098NCIT5703030 |
| Date | January 2010 |
| Creators | Wen-Yong, Wang, 王文揚 |
| Contributors | Wen-Chien, Hsieh, 謝文健 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 70 |
Page generated in 0.0103 seconds