"DC Fan" leaf number and amount of wind: when the speed has reached the limit, to increase the amount of wind, the only way to change the angle of the blades or vanes increase the fan air flow is proportional to the relationship. Power consumption and air volume: The ideal design is the large amount of wind power consumption, but in general, when the efficiency reaches a certain level, and the current consumption is proportional to the amount of wind. Wind speed and volume: the faster the speed of the wind blowing amount per unit time and more, so speed is proportional to the amount of wind. "DC Fan" static pressure and air flow: Known by the Boyle's law, Pl. V1 = P2. V2, so the air volume and static pressure is inversely proportional. Temperature and air volume: from Charles' law known as fixed under pressure situations, V1 / T1 = V2 / T2, so the higher the temperature the greater the volume of air, the lower the density, the more by weight, so the small fan wind resistance, at the same power consumption case, the amount of air increases. Humidity and air flow: air humidity, the greater the more water, because water is a large proportion of the higher air humidity it is more important than air, air flow naturally less. "DC Fan" rubber magnet magnetization intensity and the amount of wind: rubber magnet magnetized stronger suction denounced the greater the speed faster, higher air volume.