[Vwdiesel] PV=nRT and Hydraulics

[LBaird119 at aol.com]

In a message dated 7/21/2004 6:36:15 PM Pacific Standard Time, 
Libbybapa at wmconnect.com writes:

> Who can construct an unbiased experiment and resolve this issue?  Compress 
> liquid and release some leakage and measure temp of compressed and released 
> liquid.  I would imagine that the compression of the liquid would heat it 
> up.  The 
> release may not cool it as much as it was heated, because of the friction 
> and 
> turbulent flow of the leak.  Just a guess.  Not an educated one, and I'm not 
> 
> emotionally attached to it.
> 

  Thing is, doesn't the heat of compression come from the reduction in 
volume?  That's a different beast than pressure.  Pressure sort of depends 
on things remaining constant on the pressurized area so if you keep 
volume constant then recompressed substance replaces the released and 
you get lots of figures to run through.  Due to the lack of compressibility 
of liquids, I just don't see a lot of heat being released from the release 
of a compressed liquid as opposed to a compressed gas.  You REALLY 
see the change in temp when releasing the gas causes a change of state 
in the storage tank.  
  Anybody daring enough to stick their thumb across an open hydraulic 
line and try to squeeze it down to a fine spray?  Not a recommended 
thing to try due to the pressure but I think most of us would suspect 
our thumb would suddenly get REAL hot!  ;-)
     Loren