92mm ducting Mod?

[Autochthon]

Has anyone here ever come across a 92mm ducting Mod similar to this thermaltake 80mm one

 

[Lt.Doomsday]

you could make you own.

 

[superlyduper]

how

 

[Mr. K6]

Yah, I made my own to draw in air from outside the case.


There's an 80>92mm duct on hte heatsink which angles the air towards the center. The actual duct on the side of the case is made from a 4" wide bird feeder . I'm using a low speeds panaflo on the heatsink, but still my temps are down about 3-5C on the CPU :thumb:

 

[jwill]

fresh air duct...

for...

props to josephclemente at spcr...

cpu duct

zalman w/chrome fan

 

[legcramp]

omg....freaking sweet man.....

 

[Autochthon]

look's great Jwill. I have a thermalright 90c so I may go for a slightly different arrangement more along the lines of thermaltake. I wanted to route the air thru one of my 3 existing 80mm grills or a 60mm grill ( but fear noise created by the constriction) via a 80mm tube or duct with a fan at either end.

 

[Copenhagen69]

http://www.mnpctech.com/FanDuct.html
link to the plastic fan duct like in first post....

 

[Autochthon]

http://www.mnpctech.com/FanDuct.html
link to the plastic fan duct like in first post....

I don't think that will work. I need something that can attach to my 90c heatsink. For ex.
heat sink --> angled Ducting Mod --> 92mm fan --> 92mm to 80mm reducer --> 80 mm duct --> 80mm fan --> grill on case. The ducting mod may need to be angled as shown in the thermaltake model so as fit in the case. I point is to try and install an expansion chamber between fan and HS but avoid drilling a hole in side of case.

 

[Copenhagen69]

http://www.casecooler.com/evairdua.html
something like this?

 

[Mr. K6]

Damn Jwill, looks nice. Yah, I'm not into looks, as you can see . I tried putting a filter on mine, easily made the fan sound twice as loud, so no go there. If you use a basket like jwill did, the fan will start sucking air in through the holes and very little through the filter, so bad idea there too.

 

[Autochthon]

http://www.casecooler.com/evairdua.html
something like this?

That will work for the duct tubing portion but it's the the angled "Duct Mod" expansion chamber that I'm not finding. I'd just gut a 92 mm fan use that as the expansion chamber but 68mm (HS) + 25mm (expansion chamber)+ 25mm (fan) + 15mm (reducer) = 133 mm, I have about 170 mm of space to work with and 40 mm isn't enough to fit that duct tubing I'll either have to abandon that portion or custom build something.

 

[Copenhagen69]

ooooh..well then
id say custom build ya something...
go to lowes or home depot....
they got all sorts of stuff to use....
its where i get my plexi glass and modders mesh and soon to be fan duct....

 

[jwill]

...If you use a basket like jwill did, the fan will start sucking air in through the holes and very little through the filter, so bad idea there too.

actually you can see there is plastic around the mesh (from a cdr spindle) for the air to be tunneled, so the filter idea should work.

 

[Ice Czar]

Has anyone here ever come across a 92mm ducting Mod similar to this thermaltake 80mm one

first time I saw one was about 2001
about the time I joined the forum
reinventing the wheel is a very popular pastime

 

[Autochthon]

first time I saw one was about 2001
about the time I joined the forum
reinventing the wheel is a very popular pastime

links man I need link!!!

 

[Ice Czar]

well the first one I saw is long gone
the forums get pruned every few years
in overclocking and cooling a direct fresh air duct is a widely known, simple and highly productive mod, about three years ago I hooked up a 3 inch squirrel cage blower to one (it was outside the case) fed it AC air and just a bare heatsink.

hit between 27 and 30C at full load 1800+
funny thing was the exhaust from the heatsink would wash over the mobo sensor and as the AC kicked on and off the SYS temp would sometimes report higher than the CPU temp

Ive seen a few dozen different ones from ghetto to real nice like jwills there
(mine was ghetto )

 

[Copenhagen69]

those are some awesome temps....
hopefully mine get that low whenever i get around to makin one...

 

[Ice Czar]

well you cant go lower than the ambient temperature without phase change
which is what that indirectly is since I fed it via the Air Conditioner
the blower was 3" Diameter and about 3" deep for the squirrel cage and had a honking big AC motor (for the size of the squirrel cage) it was providing say 400 > 500 CFM (not sure got it at a garage sale, think it might have been a bathroom exhaust) through a square channel directly to a very old very low tech CoolerMaster Heatsink (Aluminum)

there was simply a low enough ambient temperature, and a high enough static pressure and airflow to maintain the heatsink at or near the ambient

a more typical expectation with this mod is to drop 5 > 10C over your current temps
(depending on how well ventilated your box already is and the total heat production in it)

and a cut and paste

--------------------------------------------------------------------------------------------------------------------------------

boning up on Fans might be helpful as well
its not just the airflow that is important, but the static pressure
a supply with a greater resistance will benefit from a higher static pressure



Air Flow Vs. Pressure Characteristics
Parallel & Series Operation
Stall of Axial Flow Fans

Basic Fan Laws
How to measure Airflow vs Pressure
How to Achieve Low Noise
Accoustic Noise
EMI
Introduction: Forced Convection Cooling
How to select the right fan or blower
Step 1: The Total Cooling Requirements
Step 2: Total System Resistance / System Characteristic Curve
Step 3: System Operating Point

-----------------------------------------------------------------------------------------------------------------------

there are three basic components to any thermal solution:
the heat transfer interface
(in this case the heatsink\waterblock total area)

the heat transfer medium's volume\pressure to time
(in this case for airflow, with additional variables like airflow resistance
w\ water flowrate and additional variables like turbulence, jet impingement)

and the temperature differential
(where using a cooler fluid air or water has a huge impact)

a real good computer oriented guide to thermodynamics
General Heat Transfer Guide

Heat transfer is all about temperature differentials. Conduction through materials and convection away from surfaces is proportional to the temperature differential that exists. Basically the thermal resistance of a given solution changes with the temperature differential, which is why thermal solutions are rated in °C/W which leaves that variable ambient open but gives you a formula

The heat transfer through the wall follows a simple equation:
Q=k/L(T1-T2)

We can draw some interesting conclusions from this equation. First, heat transfer is proportional to the temperature difference on the object. If the temperature differential doubles, the heat transferred doubles. Second, the conduction coefficient "k" is proportional to heat transfer. If the conduction coefficient doubles, the heat transfer doubles Alternatively, for the same differential temperature, twice as much heat may be transferred. The final observation is "L". As thickness increases, heat transfer decreases. Alternatively, to maintain the same heat transfer through a material twice as thick requires twice the temperature differential.

while that addresses conductance, there is a corrallary for convection (transfer from the heatsink to a fluid (air\water\ect)
its known as Newton's Law of Cooling

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[Autochthon]

thx great reads Ice even if those engineer's can't spell It formalized a lot of idea's I'd taken for granted. I fear that common sense and trial and error will end up being my method. Too many variables for me to calulate. I suppose I should at least test if the case is under positive pressure. I have 3 .36A 80mm panaflos in parallel on the intake side and a .1A 60mm, .2 A 92 mm and 80mm PSU fan on the outlet side. Don' thave CFM's on any of them though.

My biggest issue is that I don't want to take the simple and most efficent path and just cut a hole in the side of the case; as a result I make all kinds of trouble for myself

 

[Ice Czar]

thx great reads Ice even if those engineer's can't spell It formalized a lot of idea's I'd taken for granted. I fear that common sense and trial and error will end up being my method. Too many variables for me to calulate. I suppose I should at least test if the case is under positive pressure. I have 3 .36A 80mm panaflos in parallel on the intake side and a .1A 60mm, .2 A 92 mm and 80mm PSU fan on the outlet side. Don' thave CFM's on any of them though.

My biggest issue is that I don't want to take the simple and most efficent path and just cut a hole in the side of the case; as a result I make all kinds of trouble for myself

OEMs have thermal engineers using computational fluid dynamics software like Icepac
and we always get trial and error


when you get serious about it, youll likely go get a something like a Digitldoc5
with alot of movable thermal sensors, so you can map out various cases thermal gradients and search for hotspots