百叶窗形式对蒸发空冷器迎面风速的影响

Impact of Shutter Forms on Head Wind under Bundle in an Evaporative Air Cooler

用FLUENT数值模拟方法,研究了仰角进风百叶窗和俯角进风百叶窗对管束下方迎面风速分布的影响。研究结果表明,百叶窗俯角或仰角越大,管束下方气流的竖直分速越不均匀;俯仰角绝对值相同时,俯角进风的竖直分速分布较为均匀,但气流压降较大。百叶窗进风角度以15°左右为宜,此进风角度,空冷器压降小,进入管束的气流竖直分速分布较均匀,有利于发挥全部管子的换热能力。

Based on the FLUENT software,the wind speed under the tube bundle impacted by two different forms of shutters was investigated.The greater the depression angle or elevation angle of the shutter blades,the more uneven the vertical air speed distribution under the bundle.As the absolute value of depression angle equals to that of elevation angle,the vertical air speed distribution with depression angle is more uniform than that with elevation angle,but the pressure drop is bigger than the drop with elevation angle.The angle of 15° is better than others of the shutter because of smaller pressure drop and flatter profile of wind distribution favorable to play the rolls of heat exchange of all tubes.