120mm dc blower
 

greetings all. just wondering if anyone has come across a 120mm, 12v DC squirrel cage blower in their travels. i was thinking that one of those could really push some air through a radiator. perhaps plumbing in a variable resistor for noise control as well is a good idea. i was also thinking, that for my setup, it would be a simple matter to duct from the blower to the outside of the case, leading to some good temps. as always, thanks for your time...

jason

google

check out surplus stores

goldmine-elec.com, quickar.com, mpja.com, surpluscenter.com, etc

You must be new too!

Ford Mustang blower:
(work in progress)

where is the wind sock ?

how many cfm are you looking for? If its on the lower end (24-50) I can recommend a couple EBM/Pabst Blowers (particularly if you're working with a significant space limitation)

As for CFM, i'd say in the 50-70 range. i think that my current fans are running at, or slightly below 50 cfm. i was just trying to find a way to up the airflow a bit while trying something different. i know that the squirrel cage blowers lack a "dead spot" which may help my cooling as well. i have two fans in a push-pull config with shrouds and i was thinking of adding a bit more "juice"


jason

It's coming... be cool!

ideas from #rotor, eh ?
get with it

I know where to get a surplus 120v motorized impeller thats about 5.25 OD 3000 rpm or so. I have 2 that should be here tomorow so who knows what I'm getting. if your interested I'll let you know.

JR

Lacking time these days.

Actually, I work with fiberglass with my other hobby: scale modeling. I was glad to see #Rotor's article, simply because fiberglass is an easier way to make custom shapes.

I've got a series of pics to show the latest progress. Stay tuned.

Well have a look at one of these....
http://www.ebmpapst.us/allpdfs/RG125DC.PDF
Note the head vs airflow plot.

(Plots for axial fans are available from their site too for comparison. I do urge you to compare because I am doubtfull you're actually getting 50cfm from your fans.
This fan does ~52cfm at zero head which is enough to be felt standing 1-2 meters away. Feel free to prove me wrong though.)

Its bigger than 120mm (@ 180mm ) but it fits my chevette heater core decently with a small customized alu shroud. I think it pushes alot of air - more than any axial I've experienced - but it is noisier than I expected and you'd probably be better off with a large sized blower if you can afford the space.

Anyway... EBM has a boat load of datasheets available for all sorts of sized blowers and axial fans.... typically they dont come cheap though, but the datasheets should give you an idea of what kind of performance to expect out of an appropriately sized blower.

I spent a while looking for a Conair Rotron or EBMPAPST distibuter that would deal with selling only a couple of motorized impellers...no luck, The one I liked the best was a Comair DD402112B1R. @ 4' in Dia it is physically smaller than what I came up with and moves less CFM but thats not a bad thing in this case. Rated fom 6 to 14v dc, at 12v it moves 0 CFM @ 1.1"wc and 97 CFM @ 0" wc...it should move plenty of air @ 6v. If anyone knows of a source let me know.

The Nidec Gamma 30 is about the size of a 120mm fan, if thats what you're after. They can be had for around $10 US.

well, if you don't mind a blower that isn't some monster from a heater system, This might be interesting. I don't know the exact specs on it, but it is a comair rotron 12v 250mA blower, and so far i'm pretty happy with the one that came in the mail. its very quiet compared to the two 120mm fans i got and seems to move a decent amount of air (no idea what cfm though.) figured i'd share my experience. now i just need to build my waterblock and see how the system fits together.

Why not just get a very good 120mm fan and stack them. The fans I have here at 12V will come close if not excede a blower with less noise. Their inexpensive also.

Shameless plug, I know.

stacking fans is a truly terrible idea, get one the correct size

murray13
what are you basing your suggestion on ?
most interested in making axial fans behave like squirrel cage ones

Only when cost is not an issue.

I was only comparing vs these here.

Comparing air flow at pressure. That's all.

Up here in canada... I'm pretty sure electrosonic will sell in small quantities...
http://www.e-sonic.com/acc/products....&groupname=Fan

Stuff comes at a premium though... and from the looks of it they dont have that much in stock and the lead times aren't great either... 119 days for EBM, 57 for Comair Rotron

I'm guessing it is rated @ about 45 CFM @ 0" Prolly about 2500 RPM or so. Good find. I saw it B4 and didn't bother to do calcs...just got up hpe I did them right.

Terrible in the sense of spending too much money? Too much energy for moving a given CFM through a particular resistance?
I had thought that stacking fans would not change CFM but would increase pressure - and that if you didn't have sufficient pressure it might not be a bad idea.
My own (personal, very limited) experience it that "it depends".
For instance, stacking a second panaflo L1A at 5V delivered (reported by diode but exact same system) the same temps as a single L1A at 7V. I tried measuring 12V single vs 12V stacked and got the same reported temps for stacked and not.

This may have been a special case in that the L1A at 5V is pretty much stalled trying to pull air through a 2" core.

Or it may also be a (more typical) case of me not understanding what I'm doing...

yes
I'd say you understand your results just fine
(ignore theory, look at the results)

Squirel Cage? O.k.. Almost all automotive blower motors are squirel caged, and run on 12v. But they need to be in a box of some sort to direct the airflow. The motor itself isn't that loud, its the airflow that makes it loud. Try a scrap yard, for the cheapest in price. New ones cost anywhere from $40-$80us and sometimes don't come with the fan on top. Downfall would be that they are not to be run contiuously all day all week long, as amperage can get pretty high. At the same time you can also use a blower resistor from a car to regulate the voltage.

Your right. I wouldn't stack fans. I wouldn't even sandwich them (one pushing, the other pulling) in front of each other. There will be too much air turbulence and not enough going through the radiator. :rolleyes:

Hey Ben, you have the blower motor positioned wrong. Unless, this is just a temporary install for the picture. The side of the cage should be pointing towards the radiator.

naw, come on
inductive cooling, you just have to be near the moving air
or he could reverse it and suck ?