| 摘要: |
| 管翅式换热器的翅片优化为研究热点，而对管型的研究较少。本文提出一种与圆管相同水力半径的异型管的设计方法，建立了异型管管翅式换热器空气侧换热的数值计算模型，研究了管型、迎风方向和翅片间距对异型管管翅式换热器性能的影响。结果表明：对于双排的异型管换热器，第一排管大圆迎风，第二排管小圆迎风时，空气流动最均匀，压降最低，是综合性能最佳的迎风方向排布；在所研究的圆管、椭圆管、异型管和扁平管管翅式换热器中阻力特性和综合性能最好的是异型管i，在4 m/s风速下，异型管i的压降比圆管低31.86%，性能强化评价指标(Nu/Nu0)/(f/f0)值为1.456，主要由于管间空气的净流通面积大，流经换热器受到的扰动小；此外，翅片间距越大，管型对空气侧流动换热的影响越大，在大翅片间距下，管型对换热器阻力性能及综合性能的改善效果优于小翅片间距。 |
| 关键词: 换热器 数值模拟 综合性能 异型管 |
| DOI： |
| Received:June 28, 2021Revised:August 26, 2021 |
| 基金项目:国家自然科学基金（51506004）资助项目。 |
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| Study on Performance of Special-shaped Tube-fin Heat Exchanger |
|
Xu Rongji, Wo Long, Wang Ruixiang, Wang Suilin
|
| (Beijing Engineering Research Center of Sustainable Energy and Buildings, Beijing University of Civil Engineering and Architecture) |
| Abstract: |
| Fin optimization of tube-fin heat exchangers is a research hotspot, and there are few studies on tube types. A design method for a special-shaped tube with the same hydraulic radius as a circular tube is proposed. A numerical calculation model of the air-side heat transfer of the special-shaped tube-and-fin heat exchanger was established. The effects of tube shape, windward direction, and fin spacing on the performance of special-shaped tube-and-tube-fin heat exchangers were investigated. The results showed that for the double-row special-shaped tube heat exchanger, when the first row of tubes exposed to the air is larger than the second row, the air flow is the most uniform and the pressure drop is the smallest, delivering the best overall performance in the upwind direction. When the round tube, elliptical tube, special-shaped tube, and flat tube-fin heat exchangers are compared, the best resistance characteristic and comprehensive performance is the special-shaped tube at a air velocity of 4 m/s. The pressure drop is lower than that of the round tube by 31.86%, the value of performance enhancement evaluation index (Nu/Nu0)/(f/f0) is 1.456, mainly due to the large net flow area of the air between the tubes, and there is less disturbance when flowing through the heat exchanger. In addition, the larger the fin spacing, the greater the influence of the tube type on the air-side flow and heat transfer. The large fin spacing has better improvement effects on the resistance performance and overall performance of the heat exchanger than the small fin spacing. |
| Key words: heat exchanger numerical simulation combination property special-shaped tube |
