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Moisture-proof cooling fan air volume
- May 31, 2018 -

Moisture-proof cooling fan air volume

The air volume refers to the product of the fan ventilation area and the area plane speed. Ventilation area is the area of the exit area minus the projected area at the tongue. Plane velocity is the velocity of gas flow through the entire plane, in meters/second. When the plane speed is constant, the larger the outer diameter of the blade impeller is, the larger the ventilation area is, and the larger the air volume is. The greater the volume of air, the greater the amount of heat absorbed by the cold air, and the greater the amount of heat that can be removed when the air flow is transferred, the more pronounced the cooling fan effect.

    In practical applications, the nominal maximum air volume value is not the actual amount of air flow from the heat sink. The air volume is large and does not mean that the ventilation capacity is strong. When the air flows, the air flow will encounter the heat radiating fins in its flow path, and its impedance will limit the free flow of air. That is, when the air volume increases, the wind pressure decreases. Therefore, there must be an optimal operating point, which is the intersection of the fan performance curve and the windage resistance curve. At the operating point, the slope of the fan characteristic curve is the smallest, and the change rate of the system characteristic curve is the lowest.

    Air volume refers to the total volume of air sent or sucked by the air-cooled radiator fan every minute. If calculated in cubic feet, the unit is CFM; if it is calculated in cubic meters, it is CMM, and the air volume unit that the radiator product frequently uses is CFM.

When the heat sink material is the same, the air volume is the most important indicator to measure the heat dissipation capacity of the air-cooled radiator. Obviously, the greater the amount of air flow, the higher the cooling capacity of the radiator. This is because the heat capacity of the air is certain, and the larger air volume, that is, more air per unit of time, can take away more heat. Of course, in the case of the same amount of air flow, the heat dissipation effect is related to the flow of the wind.

Air volume unit

CFS: Cubic Feet Per Second, (ft3/s)

CFM: Cubic Feet Per Minute, (ft3/min)

CMS: Cubic Meter Per Second, (m3/s)

CMM: Cubic Meter Per Minute, (m3/min)

CMH: Cubic Meter Per Hour, (m3/h)

L/s:Liter Per Second,(L/s)

L/min: Liter Per Minute, (L/min)