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From: Clemens Winkler <ClemensWinkler@gmx.net>
Newsgroups: comp.soft-sys.matlab
Subject: SimHydraulics: "Hydraulic Fluid" question
Date: Tue, 12 Aug 2008 08:05:02 -0700 (PDT)
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Hello,

the SimHydraulics toolbox provides the "Hydraulic Fluid" block, as
described here:http://www.mathworks.com/access/helpdesk/help/toolbox/
physmod/hydro/ref/hydraulicfluid.html

The mentioned formula calculates a new bulk modulus against the
"Relative gas content at atmospheric pressure" (alpha).

But let us assume, that we have pure liquid, so alpha = 0. Now there's
no dependency of the pressure at all, because all terms with pressure
vanish, due to alpha = 0.

What I do not understand is: shouldn't there still be a dependency,
even if there's no gas in my liquid? The formula provides only a
pressure-dependency for the unsolved gas in the liquid. What about the
liquid itself?

Can anyone help me to understand that?
Thanks a lot!
Clemens