water fountains with special effects

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444 American Scientist, Volume 93 2005 Sigma Xi, The Scientific Research Society.

Reproduction with permission only. Contact perms@amsci.

Water Fountains with Special Effects

Water may be the most fundamental of human needs. Its no surprise, then, that it figuresstrongly in the earliest recorded storiesthose of the Sumerians, who built a thrivingcivilization in Mesopotamia beginning around 3500 B.C. You may be surprised, how-ever, to learn that the earliest known fountain predates the emergence of Sumerian cities by about

500 years. One example has been found from about 4000 B.C. in Iran. Public fountains soon became

gathering places, and the presence of water in the garden was recognized to offer a cooling effect

(what we now know to be evaporative cooling) by the ancient Egyptians.

For the next approximately 5,900 years fountains remained for the most part driven by

gravityactivated either directly from a running source of water such as a river at a higher

elevation or from a holding tank built behind the fountain. But that certainly did not mean that

the technology was stagnant. Far from it. Fountains emerged as more than sources of water and

space conditioning; they became objects of art and entertainment. With the advent of electrical

pumps around the turn of the 20th century, and the advancement of control technology later

on, ever more ingenuity has been applied to the design of water fountains.

From Handels Water Music to Frank Lloyd Wrights Fallingwater, most people appreciate that the

sound and sight of moving water have pleasant, relaxing effects. The spectacular displays of many mod-

ern fountains can also be captivating. I am not immune to these sensations and confess to a long-term

fascination with fountainsone that began in my childhood with the soothing sound of a simple,

single-jet fountain in our familys small courtyard in Teheran, Iran, where we spent many sum-

Said Shakerin

Although they were likely invented just to deliver water, fountains became muchmore than reservoirs early in human history

Said Shakerin is a professor ofmechanical engineering at theUniversity of the Pacific, wherehe was department chairman

from 1995 until 1998, whenhe stepped down for medical

reasons. He earned his Ph.D. inmechanical engineering fromColorado State University and isa licensed professional engineer inthe state of California. He espe-cially enjoys designing fountainswith readily found objects and

materials, and hopes to designa playful fountain based on theideas of Rube Goldberg. Address:Khoury Hall 106, University ofthe Pacific, 3601 Pacific Avenue,Stockton, CA 95211. Internet:

[email protected]


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2005 SeptemberOctober 445www.americanscientist.org 2005 Sigma Xi, The Scientific Research Society.


The Fountains of Bellagio (photograph, left, courtesy of Jim Doyle, Wet Design) in Las Vegas arearguably the most spectacular in the world and demonstrably the largest and most complex.Requiring 7.5 megawatts of power, the fountains utilize more than 1,200 nozzles that shootwater jets to heights reaching 240 feet in the air. Three hundred of those nozzles move back and

forth to dance in synchrony with musicfrom the orchestral Con te Partir to Luck Be a LadyTonight to The Star Spangled Bannerfor the enjoyment of visitors. Meanwhile, 4,000 individu-ally programmed white lights illuminate the jets, along with 230 gallons per minute of fog, atnight, the main time for shows.

The Fountains of Bellagio were designed by Wet Design, of Universal City, California. Thelake covers eight acres in front of the Bellagio Hotel and contains 27 million gallons of water.Up to 17,000 gallons of that water may be in the air at any given moment. Compressed airdrives some of the jets, and a five-minute show requires about 25,000 cubic feet of it.

Fountain to the Nth Degree

Although not quite so ambitious in scale asthe Fountains of Bellagio, Hero of Alex-andrias singing bird fountain (drawing, left)is at least as innovative in its own right.A Greek engineer active during the 1stcentury A.D., Hero was perhaps the firstdesigner of fountains with special effects,and he invented many other fascinating de-vices incorporating siphons in conjunctionwith floats, cables and pulleys to create

sound and motion. These are described inThe Pneumatics of Hero of Alexandria.

Heros singing bird gets its voice from airdriven out of a vessel and through a whistle

by a continuous flow of water into the ves-sel. The bird has moods, however: At timesit sings; at other times its silent. By installinga siphon with an exit external to the vessel,Hero allowed the water to rise to the topof the siphon, at which time the contentsof the vessel started to drain. At the same

time, the bird stopped singing as air flowed

Alternating Fountains

mer nights having supper and sleeping. And it continued as I traveled and saw magnificent

fountains in Garden of Fin (17th century) in Kashan and Garden of Shazdeh (19th century) in

Mahan in Iran. My more scholarly interest in fountains began in the early 1990s, when I saw the

innovative fountains at EPCOT Center. Moreover, I have found such devices to be useful pedagogi-

cal tools in my profession of training new engineers.

In the following paragraphs I will describe a few of my favorite fountains with special effects,

starting with the latest and greatest, then backtracking most of two millennia and following up

with relatively recent designs, all organized by type. As varied as they may be, they share common

characteristics: Successful fountains blend elements of engineering and art in elegant ways.


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into the vessel from the whistle opening. When the water leveldropped below the inlet for the siphon, air was let in that ter-minated the siphoning action, and the cycle repeated.

Another alternating device used extensively in fountains isthe tipping bucket designed by the Bana Musa brothers in the9th century and perfected by Al-Jazari in the 12th century(drawing, left, adapted from Hill 1984). This fountain alternates

between a single jet (A") and several curved jets (B"). The tip-ping buckets (T and T') cause the fountain to alternate. In thedrawing, the water supply is to the vertical jet. But when thesmall orifice on the right (O) fills the right bucket (T) until itsweight is sufficient to tip on its pivot, a small protrusion onthe right side of the bucket will push the main pipe in a coun-terclockwise direction on the central fulcrum. This will causethe fountain to switch to the B" jets, and orifice O' will beginto fill bucket T', repeating the process. Al-Jazari described thisand other inventions in his 1206 work, The Book of Knowledgeof Ingenious Mechanical Devices.

The tipping-bucket idea was used for the design of the

Germaul water automat (or Big Mouth) at Hellbrunn Pal-ace, outside Salzburg, Austria, in the 17th century (drawing,left, and photograph, below, courtesy of Hellbrunn Palace). Notethat the lower jaw is a tipping bucket. When it fills with wa-ter, it tips over, grabbing a bent rod that actuates the tongueand the eyelids. Once emptied, the lower jaw returns to itsclosed position, and the cycle is repeated as long as there iswater flow into the lower jaw. This automat (a reproduc-tion) is only one of many operating at Hellbrunn Palace,which is open to the public.

water source

AB

B

B A

TT

A

O

O


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Fountains that allow the water flow to be initiated by the userare particularly charming, and potentially commercial. Theearliest interactive fountain, also designed by Hero of Alex-andria, was a coin-operated water dispenser (drawing, left).A user would drop a small-valued coin in a slot at the top of

the dispenser. The coin would fall on a lever arm actuating avalve momentarily to let out water. When the coin fell off thelever arm, the outlet was closed.

Another well-known interactive fountain is the OrganFountain built in the 16th century at Villa dEste in Tivoli,Italy. A water wheel operated bellows to pump air for theorgan, which would start playing when visitors stepped oncertain pavement-stone blocks near the fountain. A mecha-nism hidden below those blocks activated the organ keyswhen they were stepped on.

Mark Fuller and Alan Robinson (Wet Enterprises) invent-ed a fountain activated by sound sensors installed on the bot-

tom of a fountain pool. The drawing below, taken from U.S.patent 4,817,312, shows the general layout of the nozzles(22) and sensors (11A and B). When a coin is tossed into thefountain, the sensors pick up the sound waves generated bythe coin. By gating (triangulation of) the sensor outputs, thearea of the pool in which the coin was tossed can be identi-fied. The nozzle action can then be directed to that area ofthe pool. After a predetermined length of time, the fountainis turned off and is ready for the next coin.

Interactive Fountains

One exception to the rule that preelectricpump fountains were gravity fed is a com-pressed air parlor fountain patented in 1874

by Richard Briesen (drawing, left). A handpump was used to pressurize air in a waterreservoir (A), which allowed for a steady jetof water from the nozzle (D). The fountain isfilled by pouring liquid into the bowl while avalve (e) is open. Once the reservoir is about

two-thirds full, the valve is closed. The air in

Air- and Steam-Assisted

Fountains


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In 1975 Gunter Przystawik patented (3,907,204)a mechanical arrangement to rock (move backand forth) multiple nozzles for water shows syn-chronized with music and perhaps lighting. Usingan arrangement of linkages and pivots connectedto a gear motor, groups of nozzles can be made

to move together but in different directions fromother groups. The height of the water jets can also

be varied.Thomas Simmonss 1996 invention (5,524,822)

used opposing streams to produce pleasing wa-ter displays. As shown in the drawing at left, twoseparate streams (flowing through parts 92 and 93)enter conduits (91) from opposite ends. The twostreams combine and produce jets emitted fromthe openings. According to the inventor, one cancontrol the jets direction and flow rate by varying

the pressures and flow rates of the streams.

Dancing Fountains

the reservoir is then pressurized, and anothervalve (a) can be opened and used to regulate theamount of liquid discharged through the tubeand nozzle (D). Steam has also been used to drivewater jets in small fountains for indoor use.

Fuller and Robinson invented a modern ver-sion of the air-powered water display. As shownin the drawings at left, taken from U.S. patent4,852,801, water is allowed to fill in the nozzle

body, and then a blast of compressed air from astorage tank shoots most of the water out of thenozzle to great heights. This effect could be pro-duced by pressurized water as well, but it wouldcost much more to pressurize water than it doesto compress air. The fountain also refills withwater passively. Fuller and his co-inventor madeimprovements to their air-powered fountains,for example, by using computer-controlled pro-portional valves to allow water jets with varying

heights.


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Integrating fire into fountains may seem likely to be a problematic, ifintriguing, task, but several designers have been able to do so using bothgaseous and liquid fuels. Ed Pejack, of the University of the Pacific, and hisstudent Erik Eubanks designed a small-scale decorative fountain with eightwater jets surrounding a propane jet (photograph courtesy of Ed Pejack, right). Aslight wind in the proximity of the fountain causes interesting fluctuationsand separation in the flame. Flow rates of propane and water are adjustablevia appropriate valves.

Robinson and Fuller invented a fountain system (patent 4,858,826)capable of illuminating water jets with colored flames. The flame colorsare produced by solutions of various metallic salts injected from colo-rant nozzles (34 in drawing below) into the main burner (22). Note thatthe water nozzles are part 20 in the figure. Various sensors are used forsafety; for example, an ultraviolet-light sensor causes the fuel to be shutoff when the flame is extinguished, whatever the reason.

Fire on Fountains

Fountains often accompany sculptural elements, but sometimesthey become sculptures themselves. In particular, fountainswith laminar streams have become relatively common since

the 1980s in theme parks such as EPCOT Center and in shop-ping centers. Dave Ayer, Mark Fuller and Lee Sim designed alaminar-flow fountain nozzle while seniors at the University ofUtah, and Fuller later patented (4,795,092) a nozzle producinga stream with substantially no turbulence in 1989. The draw-ing at left shows a cutout of the nozzle. It is made of a cylinderwith a tangential inlet and a knife-edge orifice outlet (12).Screens (19 and 22) and a honeycomb (21) significantly reducethe turbulence and cause the exiting stream to be laminar.

Fuller and Robinson refined this design by devising a quickdiversion method by which the laminar stream can be control-

lably terminated to give the effect of slicing the stream perpen-

Laminar-Stream Fountains


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Although fountains today are primarily built for entertainment, there are excep-tions. Architect and sculptor Maya Lin, for example, designed Timetableafusion of fountain and clockfor Stanford University in 2000 (photographs, below).The fountain-clock sculpture consists of a 10-ton piece of stone that moves in anelliptical rotation, 360 degrees per year to indicate the months. A clock mecha-nism is situated in a cavity in the middle of the rock, and the clock hands have aspecial clutch to allow for slippage and prevent damage when curious onlookersgrasp the hands and stop them from moving. According to Lin, it is the first clock

mechanism to be completely immersed in water. Timetable cost $500,000.(Photographs by Mahnaz Saremi and the author.)

I have also done some experimentation with fountains myself. The photo-graphs at the top of the next page show a small-scale, decorative fountain thatcan create letters of the alphabet and simple geometric shapes with water jets.In this example, it produces the letters A and S, the abbreviation forAmericanScientist. The fountain is described in detail in a paper listed in the bibliographyto this article, but briefly, it is made of nine outlets arranged in three rows with

Informational Fountains

dicularly to its longitudinal axis(patent 4,889,283). Further im-provements (patents 4,955,540,5,078,320 and 5,115,973) in-cluded adding a mounting as-sembly used to change the angleof and reposition the nozzles sothat the laminar stream appearsto emanate from a fixed loca-tion at different angles. This al-lows varying the characteristicsof the arch-like laminar streamin dynamic displays. At left arefour laminar-flow streams cre-ating water sheets on impact inthe Bellagio Conservatory in LasVegas. (Photograph courtesy of

Jim Doyle, Wet Design.)


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three outlets per row. The jets are spaced 2 inches apart, and each is connectedto a small submersible pump. A programmable microcontroller (BASIC Stamp 2)

turns the pumps on and off as instructed. The programming is done in PBASIClanguage via a serial connection to a personal computer.

As noted earlier, I have also found fountains to be useful in teaching engineering. In particular,

although studying patents is not a routine part of engineering curricula, the practice can offer

a rich source of design knowledge and can be suitable for any class level. Reproducing simple

historical fountains can also be a useful addition to introductory-level classes. For more advanced

students, the design and construction of a special-effects fountain can be an excellent senior proj-

ect. The fountain shown in the photograph on page 449 is one such project built by a colleagueand his student. (Links to Internet resources about fountains, including their use in teaching, can

be found atAmerican Scientist Online, for which there is a link below.)

Of course, since fountain construction involves water and electricity, one must be careful in

following safety rules and procedures in general and relevant electrical codes in particular. Like-

wise, fountains that include flames must be equipped with fire-safety devicesfor example, an

automatic shut-off valve in the fuel line in case the flames go out. But these matters are also a

worthwhile part of engineering study.

Just as important, studying and building fountains has proven to energize my students, as I

hope reading about and looking at a few examples has intrigued you.

Learning with Fountains

Bibliography

Grimshaw, N. 1995. Architecture & water.Architectural Digest(JanuaryFebruary).

Helminger, B., and S. Schally. 2002. Hellbrunn: A Guide Throughthe Trick Fountains, the Park and Palace. Salzburg: ColoramaVerlag.

Hero. 1851. The Pneumatics of Hero of Alexandria, ed. and trans.B. Woodcroft. London: Taylor, Walton and Maberly.

Shakerin, S. 2001. Engineering art. Mechanical Engineering123(7):6366.

Shakerin, S. 2004. Microcontrolled water fountain: A mul-tidisciplinary project. International Journal of EngineeringEducation 20(4):654659.

For relevant Web links, consult this

issue ofAmerican Scientist Online :

http://www.americanscientist.org/

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