How does a slim radiator cooling fan work?
Cooling fans are used in automotive applications to provide airflow to the vehicle’s heat exchanger(s). The most common application is the radiator, but some vehicles may require fans for the oil, transmission, or air-to-air, heat exchangers.
To understand how the electric radiator fan works we must first understand how the radiator works in your vehicle. Vehicle radiators, or “heat exchangers,” are simply mechanical devices that transfer heat from one medium to another. In the case of an automobile, your car is using engine coolant to circulate heat away from the engine. The hot engine coolant then transfers its heat to the incoming air (ambient air), thereby lowering coolant temperatures before circulating back to the hot engine. It is the radiator that makes this heat exchange possible by forcing the liquid, in this case coolant, through thin tubes in the core. These thin-walled tubes have external fins that transfer heat to the ambient air. While the total amount of fins and the total volume of the core play a predominant role in determining the overall cooling efficiency, radiators only work as well as the volume of air that you can move through them. There are two ways to generate a greater rate of heat exchange. The first way is to increase the velocity of air moving through the heat exchanger, and the second is to increase the volume of the heat exchanger core. If the airflow velocity is zero (parked) then the radiator cannot do its job. This is where the slim performance fan comes into play.
What electric fan do I need to cool my radiator?
The correct fan size for your vehicle depends on the size of your radiator core. Generally you want the largest fan (or fans) you can fit on your radiator. This will provide the largest amount of air movement. Air movement is rated in CFM, or cubic feet per minute. CFM is a unit of measure based on the air velocity the fan provides multiplied by the surface area of the fan. ie.:
(XYZ ft/min) x (XYZ ft^2) = ft^3/min.
The higher the CFM rating, the greater the amount of heat transfer your radiator can provide for your engine.