Re: Apple IIGS Cooling

["Paul G." <carbide@egine.com>]

On Apr 10, 11:27 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:

>
> No, not a loop.
>
> The "laptop coolers" are about 10"x9"x3/8" with two very thin, quiet,
> medium-speed fans that draw air into the narrow case and vent it out
> one of the long sides.
>
> When one is placed upside down on top of a IIgs case, hot air is drawn
> upward through the case lid and then exhausted gently backward (or
> forward if you are cold ;-), where natural convection ensures that it
> will not reenter the IIgs.  The hot air withdrawn is replaced by cool
> outside air coming in from all the other holes in the IIgs case (most
> of which are on the bottom).  The power supply will be in a sea of
> cooler air, with the slight pressure differential providing assisted
> convection cooling.
>

Ah, OK, so the "laptop cooler" exhaust is at 90 degrees to the intake,
that makes all the difference. My mistake, I thought they had axial
flow.  I have to disagree on the utility of the bottom vent holes,
though- they are there, but effectively negated by the metal RF
shield.  Someone wasn't clear on the concept of convective cooling-
the big vents need to be on top, as the volume of the hot exhaust air
is greater than the volume of the cool air coming in the bottom...
-Paul