Radiator fan recommendation?

[mankx]

I'm building a full scale swamp cooler & having no junk yards handy to just grab 'whatever' is lying around, is there a known low amp model that's ideal?
Variable speed?
Thanks!
Mankx

[some seeing eye]

Use an electronic cooling fan, "boxer fan". Computer recyclers should have for free. Most are 12v DC - you can run off a battery, and bring a charged battery to test them. You can use multiple fans too, and regulate the cooling by turning them on and off.

http://www.mouser.com/ProductDetail/Orion-Fans/OD1225-12HSS/?qs=sGAEpiMZZMvuXzJ9NcThakt%252bMfQYRSTq81HMVUcpcFU%3d

[FIGJAM]

Look at the amps those fans draw for the amount of cfm.

http://www.absoluteradiator.com/FanStore.asp

If you have that kind of power available it would be cheaper to get an inverter and buy a lasco box fan from walmart. $14 (2500 cfm)

Since you'll be going AC there are a lot of pumps to choose from, also cheap.

And they still won't consume the power that those rad fans take.

Keep in mind that the bigger the cooler, the more water it will use.

A 1000 sq. ft. house here will have a 4500cfm cooler.

They use 5 gals. an HOUR!!!

I hope you post you progress and testing.

[gyre]

A blower is more efficient than a fan.
Can be quieter too.

There are two general types, high efficiency or low noise, and high flow.
Same for the muffin fans.
The good muffin fans are metal.
Electronic supply houses, hamfests, etc.
I know people that have replaced car ac blowers with these.
German made is available too.

Muffin fans may be any voltage.
Usually 5 volts in computers, but 12 and 24 volts are common too.
120 vac too.

The best radiator fans I know of are spal, of italy I think.
Not as expensive as you might think, if you shop around.
Supposed to be quieter too.

Always more efficient to use a puller, rather than a pusher for airflow.

A good trick for more efficient car ac is to add pusher fans to use as needed, especially when stopped.
This works even with mechanical stock fans pulling.

[gyre]

On cfm flow ratings, muffin fans are designed for low resistance, while radiator fans and blowers are built for high resistance.

The cfm ratings may be based on this usage.

Your design will be more drag than an open vent on a computer.

[mankx]

I think the key issue is "push" under resistance. I don't expect most computer fans (even in a bank) will do well with the resistance of ducting and the wet mat. (my first attempt at a bucket swamp cooler had little air movement.)
Automotive radiator fans can use a lot of amps, and the ones I tested would need a PWM controller to vary the speed.
Instinct tells me that using an inverter to run a 110v AC box fan, while the cheapest, is not very energy efficient. (more than just the heat lost in the inverter)
Can anyone confirm this??

I've read that the blower/cage design is great with back pressure (or pull pressure), quiet, and efficient -- so the perfect solution.
Now finding one in 12v DC... I could only find the small computer ones made mostly for rack systems I believe.
I have a couple of full sized blowers (from an Jenair oven, and some other appliance thing) that don't look easy to change out motors on.
Also, rather than the obnoxious 14" or so ducting for a big box fan (reducing would severely inhibit air flow), the blowers can move LOTS of air through 3-6" ducting very effectively.

Any thoughts?

[FIGJAM]

There are 12 volt blower fans for race cars and venting for boat bildges.

Be creative and you'll find a solution, maybe even better than mine.

Believe me I looked at a lot of options.

I'm suprised you did'nt get much air flow.

My bucket cooler moves 190 cfm with an air pressure of 17.74!!!

[gyre]

There are 12vdc blowers for almost all cars.

Mankx, are you using fans as pushers?

Never do that if it can be avoided.