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Old 01-08-2012, 02:17 PM   #20 (permalink)
drmiller100
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Quote:
Originally Posted by Shepherd777 View Post
750 mm. I don't know what 750 mm is in inches. I'm American.
about 30 inches.

Be VERY careful about the rpm you try to spin it at. Axial flow fans (traditionally a boat's propeller, but a traditional car fan sort of acts like one) the amount of air is a function of the RPM, the diameter, and the pitch of the blades.

Your's looks to be a radial flow, which functions in part as the SQUARE of the RPM. So, as you spin it faster, your horsepower requirements can go up a LOT.

Like Instarx says, the radial fans will build more suction/pressure then axial flow.

An aside. What would be REALLY cool would be to drive the fan with a hydrostatic pump - the logic would be to measure exit temp coolant out of the radiator, and drive the fan faster until the coolant temp drops.

Optionally, the a traditional fan clutch would work also, and is much simpler, and proven and cheap and an example of doing it the easy way.
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