At 07:46 AM 3/1/2006 -0500, you wrote:
>Mike Hord wrote:
> > In particular, I'm wondering about an equation describing the
> > behavior of a stream of water emerging from a hole in a
> > reservoir.  Google search terms are proving elusive.  It seems to
> > me that the equation should be pretty simple, based on depth
> > of water and size of hole.  The result should be a half-parabola.
>
>Once you have the velocity of the water as it leaves the hole, plain old
>highschool physics will give you the parabola.  The speed of the water would
>be a function of the pressure and probably the diameter at small diameters.
>I don't know how to compute that, but a few simple experiments should be
>able to provide the answer relatively quickly.

There's a square-root law between the pressure across an orifice and
the flow rate. Since it's subsonic, Bernoulli's equation for incompressible
flow will probably be close enough (in reality the flow will be a somewhat less
for real fluids such as water by 10-40%, and there are tables published
for correction).

The maximum height an ideal fluid jet goes to is calculated here from
Bernoulli's equation:
http://highered.mcgraw-hill.com/sites/dl/free/0072454261/132215/cen54261_ch12_web.pdf
In particular, see page 17.

>Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com




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