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大型工業吊扇運行在理想的情況下，您可以把超大型工業風扇吹出的風想象成柱狀的氣流，柱狀氣流的外表面就會與空氣產生摩擦，那 阻力=K1（阻力常數）*周長 通風量 =k2（速度常數）*截面積。拿一個直徑 為 730mm的風扇和直徑為 7300mm 的超做比較：  

1、直徑 730mm 的風扇：周長=0.73 × 3.14=2 .29m 截面積=0.36 × 0.36 × 3.14=0.407 平方米

 2、直徑 7200mm 的風扇 ：周長=7.2 × 3.14=22.9m 截面積=3.6 × 3.6 × 3.14=40.7 平方米 

由此可見，通過同樣面積的氣流的阻力是小風扇的 0.1 倍  

原理：大的氣流流體運動所受的摩擦力相對小，從而使大風扇能夠驅動大量的空氣卻比小風扇所需的能量相對要少! 一旦空氣的慣性得到克服，大量的空氣流動的自身動能使之只需很小的后續動力即可維持空氣的持續流動。而小型的風扇的氣流摩擦比較大，能量大部分都損耗在摩擦過程中。

The large industrial ceiling fan is ideally operated, and you can imagine the wind blown out by the Super large industrial fan as a columnar air flow, and the outer surface of the columnar air flow will rub against the air. That resistance = K1(resistance constant) * perimeter ventilation = K2(velocity constant) * cross-sectional area. Take a 730mm diameter fan and a 7300mm diameter super large industrial fan for comparison:
1, 730mm diameter fan: perimeter = 0.73 × 3.14 = 2. 29M cross-sectional area = 0.36 × 0.36 × 3.14 = 0.407 square meters
2, 7200mm diameter fan: perimeter = 7.2 × 3.14 = 22.9 M cross-sectional area = 3.6 × 3.6 × 3.14 = 40.7 square meters
It can be seen that the resistance of large fans passing through the same area of air flow is 0.1 times that of small fans.
Principle: The friction force of the large airflow fluid movement is relatively small, so that the large fan can drive a large amount of air but the energy required by the small fan is relatively less! Once the inertia of the air is overcome, the self-movement of a large amount of air flow can enable it to maintain the continuous flow of air with only a small amount of subsequent power. The friction of the small fan is relatively large, and most of the energy is lost during the friction process.