Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!batcomputer!munnari.oz.au!bruce!trlluna!titan!rhea!aduncan
From: aduncan@rhea.trl.OZ.AU (Allan Duncan)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: The Fanning of the Amiga
Message-ID: <1991Jun16.225909.26026@trl.oz.au>
Date: 16 Jun 91 22:59:09 GMT
References: <3079@public.BTR.COM>
Sender: news@trl.oz.au (USENET News System)
Organization: Telecom Research Labs, Melbourne, Australia
Lines: 35

From article <3079@public.BTR.COM>, by thad@public.BTR.COM (Thaddeus P. Floryan):
> In article <00676835659@elgamy.RAIDERNET.COM> elg@elgamy.RAIDERNET.COM (Eric Lee Green) writes:
>>>       a fan blowing ONTO a power supply will keep the supply cooler than
>>>       will a fan sucking air OVER a power supply.
>>
>>Correction: AIR blowing onto a power supply will keep the supply cooler
>>than will a fan sucking air over the power supply. Whether that air is
>>coming from a fan or from a case opening doesn't matter.
> 
> Six of one, half-a-dozen of the other!  :-)

Not really, if the fan is blowing directly onto the power supply, there
will be substantial turbulence in the  air flow which promotes heat
transfer.  Air being sucked at moderate speeds is laminar flow, and will
leaves an insulating layer of still air on the component surface.

[...]

> As just one example (which some of you have seen), I converted one of my AT&T
> 3B1 systems to a tower configuration earlier this year and showed it at the
> Silicon Valley AT&T UNIX Users' Group meeting; the overwhelming comment from
> everyone was "Is it on?" because I applied my theory of cooling to that system
> and changed the location of the fan ... the system actually runs BELOW ambient
								   ^^^^^^^^^^^^^
Eh?  Patent it quick!  (Or, look carefully at your calibration
procedure)

> (measured using a YSI 43TC multiple thermocouple temperature instrument output
> to a Gould plotter) and it's almost totally SILENT except for the whirring of
> the hard drive ... I'm using the EXACT same fan that was in the stock 3B1.  So
> it CAN be done, with filtered air, and a clean system as a (side) benefit.
Allan Duncan	ACSnet	 a.duncan@trl.oz
(+613) 541 6708	Internet a.duncan@trl.oz.au
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