Re: Doucet effect....
--- G Tanner <g1tanner@yahoo.com> wrote:
> The differential pressure from atmospheric sea level
> to the inside of a pressurized aircraft is more than
> from sea level to 10,000 ft. Ray Waterman , Bill
> Bobier, who ever sent one to China and any others
> who
> have shipped a pumpkin via Aircraft- did any of the
> pumpkins split in flight ? I haven't heard of this
> happening to any of them.
--------------------------------------------
Thanks Gordon for your input. I'm glad there are some
engineering types out there reviewing my theory.
However, modern airplanes are pressurized to stabilize
the internal air pressure in the plane so that the
passengers don't blow their ear drums and pass out at
30,000 feet. The cargo areas are also pressurized or
you would hear more than the pumpkins popping down in
the hold.
You can safely ship a pumpkin by airplane and not
worry about the Doucet Effect because the air pressure
in the plane is held almost constant during the
flight.
I thought you aeronautical engineering types would
know this.
I agree with almost everything else you say in your
post. However, nothing in your post disproves my
theory in any way. Your experiment of opening pumpkins
and not hearing whooshing sounds is a relevent
observation. (We'll call it the Gordon Tanner Whoopee
Cushion Experiment) However, I would expect that the
pressure of the air pocket in a pumpkin would tend to
normalize with the outside pressure, so that most of
the time the pressure difference between the interior
pocket of air and the outside world would be zero.
Your experiment helps prove this.
The Doucet Effect is transitory and any induced
pressure differential dissipates over time.
It would be only during periods of rapid growth, rapid
temperature change or rapid outside pressure change
that a pressure diffential would develop. The
pressure would then tend to equalize over some period
of time with the outside because the pumpkin acts like
a sealed container with a slow leak. The leak
provides the equalization. If this were not true, the
interior cavity pressure would rarely be equalized
with the outside pressure.
Think about this a little more. I have a little
engineering in my background too and I'm not ready to
roll over on this idea yet.
diana
3rd year grower,
best 587 est. 1999
A+ in physics
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