P182 and a "sandwich"

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Hypernova
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Joined: Sat May 31, 2008 2:33 am
Location: Australia

P182 and a "sandwich"

Post by Hypernova » Fri May 01, 2009 6:59 pm

Many have said that you can't have both power and silence. Well, after spending considerable time lurking in SPCR I decided to build something that would challenge that view.

Goal:
-Maximum silence during idle while maintaining safe temperature
-Maximum performance without excessive noise.
-As little dust as possible, which means keeping the filter on the intakes. Many people don't use the filter in order to have enough airflow but this means opening the case monthly to clean it, especially bad since my room gets very dusty.

Build:
Xeon 3350 overclocked to 3.2GHz
tracend 4x2GB 1066
P5E flashed to Rampage formula
4870X2
Cooler mater rs-850-emba
WD Velociraptor 300GB
Up to 8 fan active if neccessary

The build in a glance, Kama PWM on TRUE120 and S-FLEX 1600 on the back, you can also see the NB fan on the MB. The inside have Acustipack V2 triple layers on almost all surfaces. Standard 2 layers under the MB up to under the NB.
Image

The acustipacks extend all the way to the very front end of the DVD drive. I found that this significantly reduced the noise of the drive.
Image

Front fan cover after some cutting
Image

Intake grille cut down to bare minimum need to hold the air filter, you can also see the 3 layer acustipack on the door and the heart of the cooling system.
Image

The secret sauce of how to force enough air through the filter to satisfy a 4870X yet spinning slow enough. A triple fan sandwich of NMB-MAT 12G12L-BX and Saxon airflow straighteners. This triples the effective static pressure for a given rpm.
Image

A hole was cut on the case allowing front panel cables to be routed through the space next to the floppy slot. The original hole is covered up by acustipacks.
Image

Some people hate the top exhaust cover but I say its an opportunity. By weaving triple layers onto you can turn it into a muffler.
ImageImage

Unused space on front cover is filled with triple layers. This also helps blocking dust from entering through the gaps.
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I could not cut the grill on the top without making it look ugly so I just left it, there is a temp sensor measuring the exhaust temp, there is another sensor taped to the intake to make a comparison.
ImageImage

The bottom chamber is filled with triple layers where possible and the tray itself uses double layers. There is a common opinion that the middle fan is useless, what they did not think about is why. The actual reason is that the gaps at the four corners of the separators have gaps that allow air to be recycled from the PSU chamber into the HD chamber. By using an wide I shaped piece of triple layer the fan can now properly work as intended which is pulling air into HD chamber from the front filter. In practice with the S-FLEX at 480 rpm it reduces the PSU chamber temp by at least 5 degrees. This also have the advantage of having the fan absorbed by the inside of the case instead of near the front which makesthe fan noise harder to block
Image

fan(temp)
sandwich (intake), back/top(exhaust), dominator fan (ram), bottom (taped to top of PSU)
Image

The usual idle [gaming] fan speed:
top/back-540[700]
sandwich-540 to 700 in summer [900 to 1000]
bottom-480 to 540
CPU-680 [speedfan controlled up to 1200 when CPU reach 60+]
Ram and NB - off unless I want to play with more overclocking

One other important factor is keeping idle heat low, this is by under clocking the 4870X2 to 275 GPU 0.9V and 300 Vram when idle. You can shave at least 10C of heat and about 10W at the wall. This allows the GPU fan to stay at 1200 rpm at all time in idle which is inaudible inside the case.
Total power at the wall using a some cheap power meter is ~184W. Peak power running burn-in's can reach 450W.

Final result:
idle, The whole system is subjectively quieter that a tri-cool at low. the biggest subjective noise source is the coil whine from the samsung 245B and my ceiling light. The system only emits a faint whoosh.
Gaming, perceivable noise from the sandwich, but it is easily drowned out by the noise of the game especially using when headphones. And it's only as loud my brothers P182 with use tricools at med at all time.(he explicitly states that noise are not a issue for him :? )

Sidebar on my 2nd monitor, at 19.5 intake temp:
Image

JamieG
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Post by JamieG » Fri May 01, 2009 8:13 pm

Looks pretty good!

Is the triple fan sandwich really necessary though? (It may be, I'm just curious if you have tried just one fan being ducted through towards the 4870X2).

Also, your fans are all hard-mounted with screws. Some soft rubber mounts would be something worth trying. I use a combination of these and the Nexus version of these that come with Nexus fans in my P182.

(Australian website only, but I'm sure you should be able to find them in one of your local stores).

Hypernova
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Location: Australia

Post by Hypernova » Fri May 01, 2009 8:28 pm

JamieG wrote:Looks pretty good!

Is the triple fan sandwich really necessary though? (It may be, I'm just curious if you have tried just one fan being ducted through towards the 4870X2).
You need it if you want to use air filters as the impedance kills almost all air flow without enough pressure.

"Also, your fans are all hard-mounted with screws. Some soft rubber mounts would be something worth trying. "

Soft mount isn't really necessary when the fans are under 800 rpm most of the time.

Ash
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Post by Ash » Tue May 05, 2009 12:04 am

that is nice.
i did a similar job about a year ago with acoustipack and posted pics aswell, done know where that thread has got to now though.

doesnt the sandwich make cause more noise though? i have to slipstreams using the hdd cage to mount the 2nd. 1 controlled by the MB and the other set at around 600.

the psu chamber is interesting, i took the fan out, as i didnt want another fan in the system. but have what difference did it make to the hdd temps?

also, i have never got around to cutting away the edges of the grill at the front. what did you use to cut it, nice job. mine has been sitting there with the jagged edges since i cut the middle away.

Hypernova
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Location: Australia

Post by Hypernova » Tue May 05, 2009 2:37 pm

Ash wrote:that is nice.
i did a similar job about a year ago with acoustipack and posted pics aswell, done know where that thread has got to now though.

doesnt the sandwich make cause more noise though? i have to slipstreams using the hdd cage to mount the 2nd. 1 controlled by the MB and the other set at around 600.

the psu chamber is interesting, i took the fan out, as i didnt want another fan in the system. but have what difference did it make to the hdd temps?

also, i have never got around to cutting away the edges of the grill at the front. what did you use to cut it, nice job. mine has been sitting there with the jagged edges since i cut the middle away.
You do get additional turbulence noise at 900+rpm but remember the whole point of the sandwich is that you won't have to do that often, Plus with the triple layer acustipack on the door it will block out most of that anyway.

The HDD chamber fan makes a huge difference on temps. The VC never exceeds 35C. Although indeed the PSU fan would have been enough if you don't use the air filter. With the filter on though if you try to depend on the psu fan you will get next to no airflow.

Cutting was done by diagonal cutter. Ryobi not dremel brand since the store my bro works at don't stock them. But I get to use his employee discount. Blade is steel-diamond disc. Finish with sandpaper.

xev
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Post by xev » Tue May 05, 2009 7:40 pm

I'm liking your sidebar, is it the vista version, or from desktopsidebar.com?
I tried the site and didn't find the graphics and cpu info that you have as an option

Hypernova
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Joined: Sat May 31, 2008 2:33 am
Location: Australia

Post by Hypernova » Tue May 05, 2009 8:53 pm

xev wrote:I'm liking your sidebar, is it the vista version, or from desktopsidebar.com?
I tried the site and didn't find the graphics and cpu info that you have as an option
They are all on the MS sidebar database.

Ash
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Joined: Tue Apr 15, 2008 12:36 pm
Location: London

Post by Ash » Wed May 06, 2009 12:14 am

thanks hypernova

i guess you would be the best judge as to how effective your cooling is in relation to noise level aswell but all in all its a nice build.

iv been considering placing a thin scythe fan at the front of the bottom chamber for cooling the HDD's. as i have the dust filters at the front i guess you are right about them limiting air flow. but my apartment is really dusty, i could clean it now, and come back in 30 minz and find more dust in the same place. so the filters are a must for me.

the lower chamber with just the psu fan has no dust in it, but the upper chamber with the 2 slipstreams takes in a lot of dust, although most of it stays on the fans and in the HDD cage between them.

but i opened it up to clean it after a long time as i had been busy, i found the cpu fan and heatsink had a lot of dust in there, which i can not get to without taking it out. with the acoustipack it can sometimes be a pain to take out the MB and put back again.

iv been considering removing the top fan or blocking it off, i still have some acousipack left over so i may copy your 'muffler' and switch the fan off that the top with the sunbeam fan controller.

i need to get a better cutter, and il finish off when i get time. if i get time.

Hypernova
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Post by Hypernova » Thu Jul 16, 2009 5:08 pm

[UPDATE]
Some new pics.

Mess at the back
Also stuck a piece of foam on the PSU temp probe so it can measure PSU better and not just the air temp of the PSU chamber.
Image

Big hole to front panel sealed up except for ground wire which is too short. And audio to avoid interference with others, though it still picks up a lot of noise. Need to work on some shielding for it.
Image

What I meant by sealing the edges of the bottom divider. This increase the effectiveness of the bottom fan.
Image

Mankey
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Post by Mankey » Wed Jul 22, 2009 10:36 am

What did you use to undervolt your video card?

Hypernova
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Location: Australia

Post by Hypernova » Thu Jul 23, 2009 2:55 am

Mankey wrote:What did you use to undervolt your video card?
Radeon BIOS Editor.

A less involved method is rivatuner, google for guides and utilities that may assist in finding out the lowest voltage you can get for your card. And note that some cards aren't supported by RT for volt tuning.

My setting for 4870X2:
GPU 0: 275MHz core 300MHz Vram, 0.9V
GPU 1: 275MHz core 300MHz Vram, 0.85V

wsxcde
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How do you reverse the middle NMB fan?

Post by wsxcde » Wed Jul 29, 2009 8:14 am

Hi, Hypernova;

How do you reverse the middle NMB fan to rotate in counter direction? I actually want to buy a Delta EFB1212LE 120x38mm Triple Blade Low Speed fan, which rotates counter-clockwise, to try this idea out. But this Delta fan is out of stock everywhere.

Thanks.

Hypernova
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Location: Australia

Re: How do you reverse the middle NMB fan?

Post by Hypernova » Thu Jul 30, 2009 5:24 am

wsxcde wrote:Hi, Hypernova;

How do you reverse the middle NMB fan to rotate in counter direction? I actually want to buy a Delta EFB1212LE 120x38mm Triple Blade Low Speed fan, which rotates counter-clockwise, to try this idea out. But this Delta fan is out of stock everywhere.

Thanks.
I didn't, that's why there are honey comb air flow straighteners between the fans. When stacking fans it's either that or as you intend to do use counter direction models. However most fans aren't sold with a counter version.

Shamgar
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Post by Shamgar » Thu Jul 30, 2009 6:49 am

Hypernova, that's an impressive P182 build. You must be happy with all the work you've done. How much did all the case dampening material cost you? Looks like you've left few stones unturned, or should I say, few case parts undamp'd.

You know, no PC is perfect and I have to take issue with something. Don't take this the wrong way.
Hypernova wrote:The secret sauce...
I hope you're not using your computer to serve your dinner on. Every chef is entitled to his secret recipes, but this time, I think you've gone too far.

RoGuE
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Post by RoGuE » Thu Jul 30, 2009 7:31 am

Don't take this the wrong way, but the fan stack is useless, despite what you may believe..and here's why.

Adding honeycomb does cut down on air circulation between fans, but it actually works against you. All that surface area adds what's called "head loss" in the stack. This head loss is a frictional loss that the fans have to fight to make a pressure differencial across them. It not only adds more work for the fans, but introduces fluid turbulance which reduces the efficiency of the fans as well. That said, without the honeycomb, it wouldn't be any better, becasue now you would see air circulation between fans, which is the opposite of what you want to achieve with the stack.

A better solution would be to keep the fan closest to the VGA card and duct to the front of the case from that fan. Preferebly, this would be a round, smooth duct. And the reason? Having a fan at the end of this duct allows the incoming air to "develop" or create a smooth velocity profile before it hits the fan. Developed flow is the best thing that ever happened to a fan. It not only improves fan efficency, but it allows you to increase fan RPM while keeping the same acoustic properties.

The solution I provided came straight out of a fluid mechanics class I took last fall. But if you'd rather read for yourself, pick up a copy of "Cooling Technicques for Electronic Equipment" by Dave S. Steinberg. You can probably find it an your local library.

I definatly see what you were trying to go for, and I think it's an interesting premise. However, the only pratical way for this sandwich to be viable would be to have a reversed direction fan in the middle (like jet engine compressors). Even then, you would experiance so much shedding it would only serve to annoy you.

Hey, at least your computer is has better EMI shielding right? lol

Hypernova
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Post by Hypernova » Thu Jul 30, 2009 2:35 pm

RoGuE wrote:Don't take this the wrong way, but the fan stack is useless, despite what you may believe..and here's why.

Adding honeycomb does cut down on air circulation between fans, but it actually works against you. All that surface area adds what's called "head loss" in the stack. This head loss is a frictional loss that the fans have to fight to make a pressure differencial across them. It not only adds more work for the fans, but introduces fluid turbulance which reduces the efficiency of the fans as well. That said, without the honeycomb, it wouldn't be any better, becasue now you would see air circulation between fans, which is the opposite of what you want to achieve with the stack.

A better solution would be to keep the fan closest to the VGA card and duct to the front of the case from that fan. Preferebly, this would be a round, smooth duct. And the reason? Having a fan at the end of this duct allows the incoming air to "develop" or create a smooth velocity profile before it hits the fan. Developed flow is the best thing that ever happened to a fan. It not only improves fan efficency, but it allows you to increase fan RPM while keeping the same acoustic properties.

The solution I provided came straight out of a fluid mechanics class I took last fall. But if you'd rather read for yourself, pick up a copy of "Cooling Technicques for Electronic Equipment" by Dave S. Steinberg. You can probably find it an your local library.

I definatly see what you were trying to go for, and I think it's an interesting premise. However, the only pratical way for this sandwich to be viable would be to have a reversed direction fan in the middle (like jet engine compressors). Even then, you would experiance so much shedding it would only serve to annoy you.

Hey, at least your computer is has better EMI shielding right? lol
Actually I did some crude experiments before I went ahead.

2 Tri-cools stacked with or with out honey comb, sticking a piece of paper 12x12cm to the output and see how high it's blow upward:
without honey comb and with filter - 2cm, you can also clearly hear the 2nd fan stalling.
with honey comb and filter - 7~8cm
no filter single fan - 6cm
no filter two fan with honey comb: 9~10cm

So the interesting conclusion is that yes you will lose peak performance due to friction loss but the increased back pressure more than make up for it. The friction is not that big due to the honey comb been made of very thing sheet aluminium, from what I can tell less than 0.2mm.

And from a book on googlebook on fans (name of which escapes me), besides the reverse fans straightening the output before feeding it to the 2nd fan is also a valid strategy. As long as the friction loss isn't that great. Besides, your method would only allow two fans given the space.

RoGuE
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Post by RoGuE » Thu Jul 30, 2009 4:27 pm

I see..

well, I was goin for a single fan solution..and ditching the stack. But honestly, if it works..why not I guess.

Sometimes I analyze things a bit too much, I guess its my engineering background.

Although I still think my method would preform better given constant acoustics, if the stack works for you, it's definitely a cool thing to have in ur case! haha (pun intended)


It seems like you have a passion for cooling, and the mechanics of it all, which I share with you. Nice job on the rig.

Hypernova
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Post by Hypernova » Thu Jul 30, 2009 6:30 pm

RoGuE wrote:I see..

well, I was goin for a single fan solution..and ditching the stack. But honestly, if it works..why not I guess.

Sometimes I analyze things a bit too much, I guess its my engineering background.

Although I still think my method would preform better given constant acoustics, if the stack works for you, it's definitely a cool thing to have in ur case! haha (pun intended)


It seems like you have a passion for cooling, and the mechanics of it all, which I share with you. Nice job on the rig.
I got a degree in Compsys eng too.:wink: It's important to experiment to verify theory.

My method is certainly a far cry from the optimal solution. It was simply the best I could come up with given the space restraints. If it wasn't for the filters this would have been a colossal waste of $ and time. As it is my room is just too dusty.

My real passion is not really cooling nor silence, it is simply confort.

And this is technically my very first ever build. Before that I had a laptop so I'm used to low noise.

My dream build if I ever get rich is a sound proofed room where it has it's own filtered and chilled air feed, a small hole leads to the screen and KB/M to the next room and then I can use what ever ear piercing cooling there is and OC to my hearts content.

Hypernova
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Post by Hypernova » Thu Jul 30, 2009 6:55 pm

Thought I should do a little winter update while I'm at it:

-The fan stack speed is reduced to 570~630. It simply can't go lower than that as I can't hear any changes, the biggest noise source is the air passing the filter. However it is a smooth whoosh.
-The most annoying source of noise now is actually the transformers in the florescent light on the ceiling and inside my SS 245B LCD. Some day I'm going to rip it open and add some hot glue to the offending coil.
-something I forgot to mention in the original post but can be seen in the photos, The 2nd HDD LED is actually serving as the power LED. Thus when the door is closed no light is showing from the front of the case. Makes it easier to sleep at night as the original power LED is quite blinding.
-I bought a WD20EADS and the extra sata cables can be seen in the update post. It didn't add any perceivable noise in the annoying range.

@Shamgar
"How much did all the case dampening material cost you?"
I got them from FrozenCPU.com. Things were extra expensive for me with the added shipping cost. Luckily they were bought when the NZD/USD were still good.

The X3350 which is actually just a Q9450 was bought from US too and even after shipping and duty (nasty surprise) it was still 10NZD cheaper then getting a Q9450 locally. Plus the intel sticker says you have a server CPU :P so there's a small fun factor in it.

ddrj
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Post by ddrj » Thu Jul 30, 2009 8:11 pm

Hypernova wrote: ............
@Shamgar
"How much did all the case dampening material cost you?"
I got them from FrozenCPU.com. Things were extra expensive for me with the added shipping cost. Luckily they were bought when the NZD/USD were still good.
......
thanks for this, i was wondering the same thing too

speedkar9
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Post by speedkar9 » Tue Aug 04, 2009 11:00 am

RoGuE wrote:Adding honeycomb does cut down on air circulation between fans, but it actually works against you. All that surface area adds what's called "head loss" in the stack. This head loss is a frictional loss that the fans have to fight to make a pressure differencial across them. It not only adds more work for the fans, but introduces fluid turbulance which reduces the efficiency of the fans as well. That said, without the honeycomb, it wouldn't be any better, becasue now you would see air circulation between fans, which is the opposite of what you want to achieve with the stack.

A better solution would be to keep the fan closest to the VGA card and duct to the front of the case from that fan. Preferebly, this would be a round, smooth duct. And the reason? Having a fan at the end of this duct allows the incoming air to "develop" or create a smooth velocity profile before it hits the fan. Developed flow is the best thing that ever happened to a fan. It not only improves fan efficency, but it allows you to increase fan RPM while keeping the same acoustic properties.

The solution I provided came straight out of a fluid mechanics class I took last fall.
I too come from an engineering background, and have to agree with this (haven taken Fluid Mechanics this past winter 8) ). All those Fluids terminology are now haunting my memory.... lol

Its always interesting to notice how theory matches up with reality. My sense would have told me to also go with the single fan near the video card, with a duct going to the front of the case (or perhaps the case fans themselves as a round duct with their rotor, motor and blades chopped off).

RoGuE
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Post by RoGuE » Tue Aug 04, 2009 1:02 pm

speedkar9 wrote:(or perhaps the case fans themselves as a round duct with their rotor, motor and blades chopped off).
Now THATS a cool idea. Or maybe using 1 bored out fan as a diameter "holder" and put some aluminum flashing rolled up inside the bored out fan. damn..all these ideas are gonna make my next build so fun

Hypernova
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Post by Hypernova » Tue Aug 04, 2009 3:57 pm

Given that you guys are the ones with the fluid dynamic stuff. Perhaps you guys can calculate the minimal distance needed between two 38 or 25 mm fans for the flow to sooth themselves. Given that following facts:

1) My experiment shows 0mm space will just stall the 2nd fan
2) Honeycomb for about 20mm and then 5mm free space works good enough.

3) The delta dual fan is 76mm, assuming the fans are 25mm models that means they thought with counter fans 26mm space is still needed to be optimal. So for two 25mm same direction fans the distance will be longer.

Personally I think an empty frame with say slipstream's impeller facing out would would work. Don't have the money to experiment though.
Last edited by Hypernova on Tue Aug 04, 2009 4:07 pm, edited 2 times in total.

Hypernova
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Post by Hypernova » Tue Aug 04, 2009 4:00 pm

DP
Last edited by Hypernova on Tue Aug 04, 2009 4:02 pm, edited 2 times in total.

Hypernova
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Post by Hypernova » Tue Aug 04, 2009 4:01 pm

gahh, keep clicking quote instead of edit

RoGuE
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Post by RoGuE » Tue Aug 04, 2009 5:02 pm

Hypernova wrote:Given that you guys are the ones with the fluid dynamic stuff. Perhaps you guys can calculate the minimal distance needed between two 38 or 25 mm fans for the flow to sooth themselves. Given that following facts:

1) My experiment shows 0mm space will just stall the 2nd fan
2) Honeycomb for about 20mm and then 5mm free space works good enough.

3) The delta dual fan is 76mm, assuming the fans are 25mm models that means they thought with counter fans 26mm space is still needed to be optimal. So for two 25mm same direction fans the distance will be longer.

Personally I think an empty frame with say slipstream's impeller facing out would would work. Don't have the money to experiment though.
There's an old saying in engineering and it's this..

K.I.S.S. (keep it simple, stupid!)

More often than not, it's the simple solutions that work the best. That's why I still think my solution of just 1 fan and a duct would work the best. It's simple, employ's basic fluid dynamic principals, and has a lower chance of failing ( more fans = greater chance one of them is gonna wear and start making noise).

I wasn't really sure what you were getting at with your question in this quote..maybe you could rephrase it and ill try to help you out?

Hypernova
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Post by Hypernova » Tue Aug 04, 2009 7:49 pm

RoGuE wrote:
Hypernova wrote:Given that you guys are the ones with the fluid dynamic stuff. Perhaps you guys can calculate the minimal distance needed between two 38 or 25 mm fans for the flow to sooth themselves. Given that following facts:

1) My experiment shows 0mm space will just stall the 2nd fan
2) Honeycomb for about 20mm and then 5mm free space works good enough.

3) The delta dual fan is 76mm, assuming the fans are 25mm models that means they thought with counter fans 26mm space is still needed to be optimal. So for two 25mm same direction fans the distance will be longer.

Personally I think an empty frame with say slipstream's impeller facing out would would work. Don't have the money to experiment though.
There's an old saying in engineering and it's this..

K.I.S.S. (keep it simple, stupid!)

More often than not, it's the simple solutions that work the best. That's why I still think my solution of just 1 fan and a duct would work the best. It's simple, employ's basic fluid dynamic principals, and has a lower chance of failing ( more fans = greater chance one of them is gonna wear and start making noise).

I wasn't really sure what you were getting at with your question in this quote..maybe you could rephrase it and ill try to help you out?
Basically if one is to use a simple gap and not have any special fins to straighten the flows between the fans, how far of a gap are we looking at?

And I noticed you mention only one fan, the whole point of this exercise is to combine the static pressure of multiple fans to over come air filters. There is no point to any of this if you are only going to use one fan.

RoGuE
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Post by RoGuE » Tue Aug 04, 2009 8:44 pm

I dont know how tight knit your filter is, but if one good slipstream fan cant make enough pressure to pull air in, then ill be damned.

The fact is, it can. And making the sandwich is really, and truely pointless if you can just duct to the front of the case.

Either you need to invest in a better fan, or replace the air filter you have with a higher quality, less restrictive filter.

If you are still dead set on making a fan stack, the only practical way of figuring out spacing is experimentation. It would take an enormous amount of brain/computing power to model the fluid dynamics in your fan stack.

Hypernova
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Post by Hypernova » Tue Aug 04, 2009 9:09 pm

RoGuE wrote:I dont know how tight knit your filter is, but if one good slipstream fan cant make enough pressure to pull air in, then ill be damned.

The fact is, it can. And making the sandwich is really, and truely pointless if you can just duct to the front of the case.

Either you need to invest in a better fan, or replace the air filter you have with a higher quality, less restrictive filter.

If you are still dead set on making a fan stack, the only practical way of figuring out spacing is experimentation. It would take an enormous amount of brain/computing power to model the fluid dynamics in your fan stack.
I'm just using the stock P182 filter, and it will certainly cut down on the intake without some effort. Like my experiment showed you are left with somewhere near <30% of free air throughput with filters for a single tri-cool. A slip stream will of course manage to suck 'some' air, but I can guarantee it will be at volumes next to useless for a 170 W idle rig.

frenchie
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Post by frenchie » Tue Aug 04, 2009 11:37 pm

How about with the fan at an angle at the end of the tube ? does that change anything ?

In other words, does the tube have to be in line with the fan to keep all those nice properties ?

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