No box needed if you're using a squirrel cage fan for suction...
http://koure.org:800/temp/mounted_impeller.jpg

slick, be nice to test
any comparative 'feel' Bob ?

hmm, after going through the posts, and doing a bit of internet research, i've found that really what i'm looking for is a bit out of hand. a blower with a 120mm square outlet would probably be a little large, and/or noisy. i notice that most of the blowers in the smaller range are all relatively flat with narrow rectangular outlets. even with a shroud, i'd still worry about air only being directed through a certain cross section of the rad. i was hoping that somewhere in the world, someone was making a 120mm blower like a scaled up version of the Coolermaster Aero 7. then again, i had an aero 7, and at full tilt, it sounded like i had a hair dryer running in my case (one of the reasons why i switched to water cooling). maybe i can gang four aero 7's together in a single shroud, that would be interesting....

jason

bob knows what I was saying

IIRC, that blower was less than 70CFM freeflow

aero7s are weak

how much cubic space do you have to work with? dimensions?

i have a chieftec matrix full tower case with the fan/shroud/rad/shroud/fan mounted to the roof of the case, a little rearward of center. i'd say i have 7.5"x6.5"x6.0" to play with at the moment. this was my first wc attempt so i placed things the best i could so that i could remove most any component without having to drain and remove the wc setup. here's a pic, hopefully, that may help...

@ bob, very nice. looks like what i'll be doing as i think i've got both the same blower and very similar rad. any test runs of that yet?

That would be contrary to the normally expected flow path of an ATX case (not that i'll be anywhere near a typical ATX setup!). Rear exhaust works really well for me.


I've found that a blower would have to be 4" or 5.25" in diameter, to have a decent amount of flow. Based on specs, where undervolting to 7 volts works. Run silent, run deep. ;)

whatever works for you, I just think you are losing major efficency by making the air change directions so many times, not to mention the air will be preheated by whatever's in front of the blower (maybe nothing, unsure of your final setup)

your PSUs are in the front, aren't they? kinda running the reverse of a normal setup anyway?

Ohhhhhh...... that type of squirel cage. Yeah, looks efficient. Takes a lot of space though, doesn't it?

Your not understanding what I'm saying. The way the fan blades of the "Blower Motor" works is sort of like a water mill. Picture this: If the water mill spins at 5000 rpm it'll pick up the water and throw the water beside itself from the centrifugal force. Not in front of itself.

If you look where the blower motor sits in your car, it is always positioned sideways from the heater core and the evaporator.

hey mars, you're missing it...

look at that pic you quoted

the plastic cage with the blades PULLS that air from in front of it and THROWS it out to the sides

no shroud needed

got it?

Hhmmmmm........I see what you are saying. Your going to divert the air to tunnel it backwards. Possibly in a cyclonic way. I don't know how efficient that'll be.
When I say 'I don't know', I mean you are the first person I know to use the 'Blower Motor' like that. I can tell from your posts that you are an intelligent man with excellent ideas, and strong knowledge.

Let us know how it works out, so we to can benefit from your ideas.

all clear now?

I see the pic. You are right. However, I am referring to an automotive Blower Motor. Not the pic above.

If your implementing that the "automotive Blower Motor" will work the same way as the pic above, I've never seen it that way. They are 2 different fans performing different ways. Only Big Ben, will know how well it works when he completes his project.

any blower with a cage will work for it

Exactamundo! :D

Given the shape of the shroud, I expect the airflow to be concentrated along the outer edge of the heatercore (and yes, possibly cyclonic): I just hope that there's no reflow within the center area of the core. I might have to put a bunch of little ribbons to observe the actual airflow. Worse case, I'll have to block the center area of the core, but that's really no big deal, because the airflow will most certainly be there, and the core is still relatively large, at 6" by 8". No big loss.

Right now the main issue I have is connecting the shroud to the core, but it's a minor problem. Mounting the blower is resolved, it just needs to be done.


The pic above looks a lot like JFettig's implementation of a blower on a core. Very easy to do, it's just hard to find the motorized impeller for a decent price. Allelectronics.com had one for a while, but it was seriously under-rated, as I discovered here:
http://forums.procooling.com/vbb/showthread.php?t=7314
(never mind the first few posts :D )

an "automotive blower" works the exact same way as the blower pictured (in fact, the blower pictured could be an "automotive blower", whatever that means, lol)
the difference is in your mind - all blower/squirrel cage fans work on the same exact principles.

Actually that there are two types of blowers shown, one forward inclined and onebackwards. Both have their advantages, forward is quieter, but reverse works non overloading, that is it works better against restrictions. It'll be interesting to see results....too bad it's so hard to quantify noise levels.

What will you use to dampen vibration? Rubber washers?
I understand the issue you have, and I think now's the time to face it: This is one of the rare moments in your life where it's OK to use duct tape. It's really OK.

Larger blowers get connected/shrouded with heavyweight plasticized cloth. It won't rattle, and allows some play in installation. A lightweight plasticized cloth is duct tape.

Any chances of posting links? I'd like to learn about the differences.
I'm guessing that forward inclined means the blades tip inwards in the direction of rotation? And so pull from the center and expel to the outside? (btw, the forum editor wants to change o-u-t-w-a-r-d-s to ****wards - is this some kind of rude language I don't know about?)
Backwards inclined means the reverse of this? Blades tipped to the outside? Flow towards the center? This would mean that, in spite of looking like centrifugal pumps, squirrel cage fans are actually using aerodynamic lift?
Thanks!
Bob

Thank You! Finally,someone who see's the difference between the 2 fans besides me. The BLADES. They will perform differently, and I'm not sure how different. Big Ben, will make that decision when he is done.

Not, any squirel cage will do. They are not all designed the same.

How many 80mm 12v fans have you seen that have different cfm flow and rpm speeds. I've seen many.

ok, so who is going to become the squirrel cage fan man ?
it is clear we need more info

I've got to believe that a blower configured to suck is different than one designed to blow

jlrii just became our defacto "expert", just for coming up with that distinction! ;)

Yeah, I'm there.

Rubber grommets will dampen the vibration from the blower. I'm in the process of putting a frame into the case, to hold it into place. A mix of steel and aluminium, a little riveting, etc. I have muffler tape, which would be ideal. The issue right now is that the fiberglass shroud I built just barely fits over the core, and the inlet/outlet actually interfere with it, a little bit. Otherwise, the core is already sitting on sticky foam strip insulation, again for sound dampening.

I'm also looking to paint the inside of the case in flat black, so I'm going to have to do this "American Chopper" style, i.e. build the raw components, assemble, then strip it all apart for painting, then re-assemble the whole kit-n-kaboodle.

if it's a DC motor, can't you reverse polarity to reverse effective incline?

OK, this'll be my third attempt at replying. The Mozilla spell checker, when installed into firefox sometimes freezes firefox. I've done the uninstall everything / install different spell checker (actually same one but properly packaged for firefox) dance and am trying yet again (sigh...)

I do not recommend this impeller for anyone who's not primarily interested in silence. It has a tendency to shake when run at 12V, even when carefully installed. I'm using this one at 6V, and get about the same cooling (CPU diode but system otherwise exactly the same) as a single L1A at 7V (or two of 'em stacked at 5V) - and about the same noise level as the two L1As at 5V - so somewhere between 18 and 22dB.
It's an improvement over the two fans stacked as it's much smaller - and I get no change in my cooling when I replace the filter cover on the PC bezel (it's a FS020, radiator in lower front, pull only).

From looking at the Panaflo L1A fan curve for 7V, I'm probably getting 25CFM or less through the radiator.
I've been looking for one of the 5" or 6" cage fans from JapanServo (they seem to be the only cage fan manufacturers focused on making this kind of fan quieter).
I found what appear to be 4" 24V JS fans and ordered a couple to play with.
http://www.herbach.com/Merchant2/gra...01/blr4707.jpg
I am hoping that these might move the same amount of air at 12V as the one I'm using now does at 6V - but with a bit less noise.

Those look interesting. Has anyone tried them, shrouded and mounted on a heater core?

Very different blade design + typical small dc fan motors no likey reverse polarity. A forward inclined blower has a lot of small blades cupped towards the direction of flow, run it backwards and you get practically no air movement. A reverse inclined blade has a lot fewer blades that are a lot straighter, same deal if run backwards...practically no flow. As BillA noted reverse inclined seen mostly in exhaust aplications, and forward inclined for supply. Not to imply that one couldn't be used for the other, it depends on the specifics of the setup.

Tonight at work I saw the biggest blower I've ever seen. The cage itself was about 30" in diameter and about 18" deep, no motor though. I'm guessing its part of an indutrial AC system since it was coming from Carrier.