Date: Fri, 2 Jul 1999 16:41:41 -0700 (PDT)
Reply-to: classiccmp(a)u.washington.edu
From: Dwight Elvey <elvey(a)hal.com>
To: "Discussion re-collecting of classic computers"
<classiccmp(a)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