PC form factor

From: jpero_at_cgocable.net <(jpero_at_cgocable.net)>
Date: Fri Jul 2 15:07:14 1999

> Date: Fri, 2 Jul 1999 16:41:41 -0700 (PDT)
> Reply-to: classiccmp_at_u.washington.edu
> From: Dwight Elvey <elvey_at_hal.com>
> To: "Discussion re-collecting of classic computers" <classiccmp_at_u.washington.edu>
> Subject: Re: PC form factor

Snip! Good comments...

> > Allison
>
> Hi All
> Actually air flow is quite complicated. Using muffin type fans
> makes it worse. Here are some basic rules of thumb.
> 1. Fast moving air in an open space will find a surface
> and run along it.

I append: Air likes least resistance paths. Suppose: bunch of
short cards with space above it and space front of it. Most of air
will not go into it, it will bypass it.

> 2. The only way to make uniform air flow is with restriction.

In other words: ducts and shrounds?

> 3. Rotating air will do strange things until straightened
> out. ( examples, air coming from a rotary fan and also
> most air going through a single small restriction ).

Tell me about this "rotating air will do strange thing till
straightened out" what it do strange thing? And how is done to
straighten it out?

> 4. Laminar flow is best understood but turbulent
> flow removes more heat.

Correct.

>
> I have seen the above problems cause all kinds of effects
> that were not obvious at first.

Do tell your tales about this! I'm trying to design a case to do
cooling of all drives, PSU motherboard and CPU by one large quiet
fan and ducts/shrounds. Isssues: noise and reliablity from too many
fans.

> Dwight

Wizard
Received on Fri Jul 02 1999 - 15:07:14 BST