中国电机工程学报
中國電機工程學報
중국전궤공정학보
ZHONGGUO DIANJI GONGCHENG XUEBAO
2012年
5期
1-8
,共8页
涡流发生器%直接空冷器%强化传热%数值模拟%倾角
渦流髮生器%直接空冷器%彊化傳熱%數值模擬%傾角
와류발생기%직접공랭기%강화전열%수치모의%경각
vortex generator%direct air-cooled condenser%heat transfer enhancement%numerical simulation%angle of inclination
通过数值模拟研究了矩形小翼、三角小翼、梯形小翼、柱面梯形翼、柱面三角翼和柱面矩形翼等6种涡流发生器分别安装于直接空冷凝汽器单排蛇形翅片扁管中的压降和换热性能。Re数在600~1800范围内,涡流发生器采用相同高宽比、尾高、攻角以及安装位置。结果表明：矩形小翼的换热及压降增大最多,Re=1729时,相比平直翅片分别增加了14.27%和18.32%。Re=1 729时,柱面梯形翼的压力损失比矩形小翼少4.7%,换热低1.5%。当以（j/j0）/（f/f0）1/3作为综合换热性能评价标准时,柱面梯形翼的综合换热性能最好。另外,考察了柱面梯形翼倾角的影响（0°、6°、12°、20°、24°和26°）,相同工况下,倾角为12°的柱面梯形翼换热最好（较平直翅片增强4.29%~14.1%）、压降最小（增大7.5%~12.8%）且综合换热性能最好。柱面梯形翼因其迎流面积与斜边长度的匹配以及流线型柱面,具有良好的强化传热效果以及较小的压降。
通過數值模擬研究瞭矩形小翼、三角小翼、梯形小翼、柱麵梯形翼、柱麵三角翼和柱麵矩形翼等6種渦流髮生器分彆安裝于直接空冷凝汽器單排蛇形翅片扁管中的壓降和換熱性能。Re數在600~1800範圍內,渦流髮生器採用相同高寬比、尾高、攻角以及安裝位置。結果錶明：矩形小翼的換熱及壓降增大最多,Re=1729時,相比平直翅片分彆增加瞭14.27%和18.32%。Re=1 729時,柱麵梯形翼的壓力損失比矩形小翼少4.7%,換熱低1.5%。噹以（j/j0）/（f/f0）1/3作為綜閤換熱性能評價標準時,柱麵梯形翼的綜閤換熱性能最好。另外,攷察瞭柱麵梯形翼傾角的影響（0°、6°、12°、20°、24°和26°）,相同工況下,傾角為12°的柱麵梯形翼換熱最好（較平直翅片增彊4.29%~14.1%）、壓降最小（增大7.5%~12.8%）且綜閤換熱性能最好。柱麵梯形翼因其迎流麵積與斜邊長度的匹配以及流線型柱麵,具有良好的彊化傳熱效果以及較小的壓降。
통과수치모의연구료구형소익、삼각소익、제형소익、주면제형익、주면삼각익화주면구형익등6충와류발생기분별안장우직접공냉응기기단배사형시편편관중적압강화환열성능。Re수재600~1800범위내,와류발생기채용상동고관비、미고、공각이급안장위치。결과표명：구형소익적환열급압강증대최다,Re=1729시,상비평직시편분별증가료14.27%화18.32%。Re=1 729시,주면제형익적압력손실비구형소익소4.7%,환열저1.5%。당이（j/j0）/（f/f0）1/3작위종합환열성능평개표준시,주면제형익적종합환열성능최호。령외,고찰료주면제형익경각적영향（0°、6°、12°、20°、24°화26°）,상동공황하,경각위12°적주면제형익환열최호（교평직시편증강4.29%~14.1%）、압강최소（증대7.5%~12.8%）차종합환열성능최호。주면제형익인기영류면적여사변장도적필배이급류선형주면,구유량호적강화전열효과이급교소적압강。
The performances of pressure drop and heat transfer of six kinds of vortex generators in single-row wavy-finned flat tube of direct air-cooled condenser were numerically investigated,respectively.The considered vortex generators including rectangular winglet,delta winglet, trapezoidal winglet,cylindrical-shell rectangular winglet, cylindrical-shell delta winglet and cylindrical-shell trapezoidal winglet which have the same aspect ratio,trailing height,attack angle and placement in the flow channel with Reynolds number（Re） ranged from 600 to 1 800.The results show that rectangular winglet has the best heat transfer enhancement and the largest pressure drop with factors j and f are 14.27% and 18.32% higher than those of the flat tube for Re=1 729 respectively.The pressure drop and heat transfer of cylindricalshell trapezoidal winglet are much lower than the rectangular winglet by 4.7% and 1.5% at Re=1 729 respectively.With regard to the comprehensive factor [（j/j 0）/（f/f 0） 1/3 ],cylindricalshell trapezoidal winglet has better overall performance.In addition,the effect of angle of inclination of cylindrical-shell trapezoidal winglet（0°,6°,12°,20°,24° and 26°） were evaluated and the results show that cylindrical-shell trapezoidal winglet with angle of inclination of 12° has the best heat transfer enhancement（4.29%~14.1% more than the flat tube）, lower pressure drop（7.5%~12.8% larger than the flat tube） and the comprehensive performance.This results from the optimal combination of the projectional area facing air flow with the length of inclined edge as well as the streamlined surface structure.
