In the Las Vegas Bellagio Casino Botanical Garden, there is a "water pipe" arc.
This arc starts from a ground source, goes about 12 feet high and 12
feet far and returns to a ground receptacle, thus forming an arc. The
water is not encased in a covering and does not leave the approximate
1 inch pipe as it flows around the arc. how is this done so that I may
duplicate it?

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Request for Question Clarification by sublime1-ga on 08 May 2004 11:42 PDT

rwp1...

Is this an image of the arch you're describing?:
http://www.engineering.ucsb.edu/~jwilliam/Slidefilm/Vegas_Slides/Vegas%20Water%20arch.jpg

sublime1-ga

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Clarification of Question by rwp1-ga on 08 May 2004 13:30 PDT

This is an arc of water with a circular cross-section diameter of one
to two inches. The water is flowing, going upward and then coming down
forming an arc. What is amazing is that the flowing water, as it flows
in this arc does not break out i.e. does not spread apart or disperse
as, for example, water coming out of a garden hose. The cross-section
remains circular throughout the entire arc and vitually none of the
flowing water drips or falls from the arc.

The effect is achieved by the use of special laminar flow nozzles.

"The spring display at the Bellagio Conservatory & Botanical Garden is
absolutely wonderful.

The exhibit combines real and artificial butterflies, topiary swans showing
the art of mosaiculture at its finest, the special fountain technique of
laminar flow, and a very special floral tribute to a Monet painting which is
part of the current Monet exhibit at the Bellagio Gallery of Fine Art."

Travel Stories from AboutMyTravel.com
http://www.aboutmytalk.com/t83471/s&las-vegas.html

"Dave Ayer, Mark Fuller, and Lee Sim, seniors in the Department of
Civil Engineering at the University of Utah in 1976, designed a
fountain nozzle that produced a coherent and laminar stream of water.
The water jet thus produced looks like a glass rod flying through the
air. Similar fountains have been installed in several theme parks,
including Epcot Center.

After working for six years with Walt Disney Imagineering, Fuller
established his own company, WET Design, in Los Angeles, specializing
in the creation of water features. The company has designed fountains
for many locations in the United States and several cities around the
world...

In 1992, Fuller and a co-inventor, Alan Robinson, mounted laminar flow
nozzles on platforms whose angles, with respect to the ground, were
individually controllable (U.S. patent No. 5,115,973). By oscillating
the platforms, laminar streams move through the air in a beautiful
arc-like manner... WET Design also created the sophisticated and
elaborate fountains at the Bellagio hotel, operated by MGM Grand Inc.
in Las Vegas."

Mechanical Engineering Magazine: Engineering Art
http://www.memagazine.org/backissues/july01/features/engart/engart.html 

"Axisymmetric laminar flow (ALF) devices generate streams of water
with all the water particles having the same flow rate and direction,
much like photons in a laser. They look like glass parabolas of water
that seem to hang in the air. Observers really can't tell the arcs
contain moving water until the flow is switched off. Then they can
watch the well-defined tail of the curve chase the hoop of water back
into the fountain... Mark Fuller, founder of WET Design, studied ALF
and wrote his undergraduate civil-engineering thesis on the subject at
Stanford University. He later went on to feature ALF in Leapfrog, a
fountain he designed while working at Disney's Epcot Center.

'We use traditional pumps to pressurize the water, but then send it
through a series of chambers, straighteners, and baffles to line up
the flow and bring it all to the same speed. Then it leaves the
nozzle,' says Tony Freitas, a WET Design engineer. 'Most streams are
about a half-inch wide and travel 15 ft, reaching about 15 ft high.
And we can do smaller. But it gets more difficult as you make them
larger.'

Surface tension helps keep them together in an ALF stream. But when a
large stream hits the apex of its arch and accelerates downward,
different parts of the stream begin traveling at different speeds.
This warps and distorts the once coherent flow, breaking it up."

Machine Design Magazine: Making Water Dance
http://www.machinedesign.com/ASP/strArticleID/55230/strSite/MDSite/viewSelectedArticle.asp

Some interesting information about laminar flow water effects may be
found in the designers' patent, as filed with the United States Patent
Office. Here's an excerpt:

"A water display comprising a source of water under pressure; first
and second laminar flow nozzles disposed at different locations
operatively connected to the source of water, the nozzles each having
an outlet adapted to direct a substantially laminar flow stream toward
the laminar flow stream of the other nozzle to collide therewith for
viewing by observers of the water display, the laminar flow stream of
each nozzle having a predetermined trajectory projected at a
predetermined angular elevation...

Water displays utilizing laminar flow streams to create dynamic
arch-like displays are disclosed. The laminar flow nozzle is mounted
on an assembly for changing the angle and repositioning the laminar
flow nozzle so that the laminar flow stream appears to eminate from a
fixed location at different angles, which allows varying the
characteristics of the display in a dynamic manner. Simultaneous
control of the nozzle position and angle with control of the pressure
of water supplied thereto allows the stream to be varied to create a
dynamic display with the stream returning to a sink region at a fixed
position independent of the height of the water stream."

USPTO Patent Full-Text and Image Database: Patent #5,115,973
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=5,115,973.WKU.&OS=PN/5,115,973&RS=PN/5,115,973

Here's the website for WET Design:

WET Design
http://www.wetdesign.com

Google search strategy:

Google Web Search: "bellagio" + "fountain" + "botanical garden"
://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=bellagio+fountain+%22botanical+garden

Google Web Search: "laminar flow" + "bellagio"
://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%22laminar+flow%22+bellagio

Google Web Search: "laminar flow" + "arc OR arch" + "water" + "fountain"
://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%22laminar+flow%22+arc+OR+arch+water+fountain

I hope this information is helpful. If anything is unclear, or if a
link doesn't work for you, please request clarification; I'll be glad
to offer further assistance before you rate my answer.

Best regards,
pinkfreud

I was also interested in different water effects, and stumbled across
your answer page. After looking through the patent, I was frustrated
at how unclear it was about the actual generation of laminar flow.

Luckily, I was in a position to look up the 1975 civil engineering
honor's thesis by David Ayer and Mark Fuller, entitled _An application
of axisymmetrical laminar flow to fountain design_.  (Although
Fuller's thesis is listed as being at Stanford, this one is at the
University of Utah).  I haven't been able to go through the entire
thesis, but it deals with some very practical problems.

Before I go on, I wish to note that I don't believe creation and use
of a laminar flow nozzle is a breach of intellectual property rights;
the patent is limited in scope to the mounting apparatus and certain
visual effects.  Since unpatented laminar flow nozzles were on public
display at Disneyworld (as mentioned in Prior Art), the nozzles are,
in fact, unpatentable.

So here's the gist of what I got from the thesis:
In laminar flow, flow lines don't cross. To approximate laminar flow,
you need a long, small tube to limit the side motion of the water--
but you also need a large-diameter tube for higher-pressure,
lower-speed flow, which brings you closer to laminar conditions.  So
the authors got a piece of acrylic tubing and packed it with a bunch
of soda straws, and did some "backyard" experimenting with it. 
There's a nice drawing of this, which I'll post as soon as I can, but
it had no dimensions I could see.  I do have another drawing from the
thesis, a larger final design with dimensions.  Find it at

http://home.utah.edu/~bjl8/nozzle_metric.gif

(It's not formatted in any way.) I'll post the other when I get the
chance. (I believe this falls under fair use of copywrighted
materials, as it is a very small portion of the whole, and is for
educational purposes.)

Anyway, the nozzle goes like this: A smaller-diameter inlet comes into
the big acrylic tube. After a short space, it encounters the first
screen, which holds in place a bunch of soda straws about 1/3 the
length of the entire tube.  A second screen holds the other end of the
straws in place.  Two more screens after that act as baffles to help
smooth the flow.  Then the water goes out an exit hole in a face
plate.  The hole is small in diameter and tapered from a razor-edged
small hole on the inside to a larger hole on the outside.

It seems from the thesis that you could play with the dimensions and
it would still work.  They started with a fine screen (50 holes/inch)
but decided 20 holes/inch was fine.  To hold the screens in place,
they used short sections of acrylic tubing that just fit inside the
larger tube.  I don't know the diameter of the soda straw pieces.  The
exit hole had to be machined to a sharp cross-section (see drawing) to
avoid disturbing the water much.

The authors aimed two of these nozzles at each other to create a
water-bell in the air.  I don't know if this is part of the patent;
since the pair created a fountain for a public building in the 70's,
it's likely not patentable-- but if you want to do this in your
backyard, you should check more carefully than I did.

The authors encountered two main problems: (1) Varying water pressure
(from the municipal source) and (2) Air accumulating in the nozzles. 
For the first problem, they decided to go with a pump or an
air-pressurized reservoir.  For the second, they decided either to
periodically drain the system and slowly refill it daily (on a timer)
and incorporate a valve (see drawing).  For their experimental system,
they just had a hand-operated stopcock in the spot where the air
accumulated, and they bled the air every so often. They also worried
about mineral accumulation, but decided it wasn't a big problem (I
can't recall why).

So that should get you started on your own backyard water pipe.  If
you have a specific question, I can research it, but my wheels grind
slow.

People obsessed with the perfect water gun:

http://www.sscentral.net/

A related fountain effect with very practical info:

http://www.hiddenmickeys.org/Imagineering/LeapFrog.html

Good luck,

Lowdero