Re: Beginner's Question about Bernoulli and Tanks

From: Uncle Al (UncleAl0_at_hate.spam.net)
Date: 02/11/05 

Date: Thu, 10 Feb 2005 16:14:22 -0800

anebt2@peoplepc.com wrote:
>
> Hello,
>
> I'm stuck with the conceptual understanding of using Bernoulli with
> open and closed tanks.
>
> With open tanks, I don't understand why both pressures at the top and
> bottom of the tank are both atmospheric and thus cancel in the
> equation. I keep thinking that the pressure in the bottom of the tank
> would be greater than the pressure on top (similar to the pressure at
> the bottom of the ocean being greater than the pressure on the
> surface).

If sea level air pressure is 760 torr, what is the air pressure at 10
feet altitude, 100 feet altitude? Feel free to convert to inches of
water.

>> With closed tanks, I'm even more confused and don't know how to use
> Bernoulli with these types of problems at all.
>
> If anyone knows how to explain this conceptually, I would very much
> appreciate it.

In a closed tank the water is a piston and /_\(air pressure) is
inversely proportional to /_\(ullage volume) assuming an initial air
fill and constant temp. 

-- 
Uncle Al
http://www.mazepath.com/uncleal/
 (Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf

Relevant Pages

  • Re: Find order of 2 for p=32833*2^1000004+1 and win $100
    ... then Hakim rightfully hunts a mushy per_cent on top of ... but will Mohammed fling that? ... Try warming the ferry's interim shop and ...
    (sci.crypt)
  • Re: hash of variable+constant
    ... He can mentally arise short and survives our good, ... sound any huge seminars. ... it finances a midnight too random per her modest business. ...
    (sci.crypt)
  • Re: Cortank
    ... A core 'tank' could be pressurized to four or five ... of the volume of the airship. ... as a resovior for gas panels that would form a protective inert gas ... The Shenandoah was lifted by a squall to above its pressure altitude, ...
    (sci.energy.hydrogen)
  • Re: Cortank
    ... A core 'tank' could be pressurized to four or five ... of the volume of the airship. ... as a resovior for gas panels that would form a protective inert gas ... The Shenandoah was lifted by a squall to above its pressure altitude, ...
    (sci.energy.hydrogen)
  • Re: Electric Motorglider Flies
    ... to produce electricity by a fuel-cell with a typical efficiency of ... You are forgetting about the enormous weight of a tank capable of ... appear that carbon fiber or Kevlar composite pressure cylinders may be ...
    (rec.aviation.piloting)