Researchers map the physics of Tibetan singing bowls

Jul 01, 2011

Researchers have been investigating the connection between fifth century Himalayan instruments used in religious ceremonies and modern physics.

In a study published today, 1 July 2011, in IOP Publishing's journal Nonlinearity, researchers have captured high speed images of the dynamics of fluid-filled Tibetan bowls and quantified how droplets are propelled from the water's surface as the bowls are excited.

The first of five videos demonstrating the intriguing dynamics can be seen below:

This video is not supported by your browser at this time.

A Tibetan bowl, generally made from a bronze alloy containing copper, tin, zinc, iron, silver, gold and , is a type of standing bell played by striking or rubbing its rim with a wooden or leather-wrapped mallet. This causes the sides and rim of the bowl to vibrate, producing a rich sound.

The unique singing properties of Tibetan bowls were utilised as a way of investigating a liquid's interaction with – a situation that arises in many engineering applications such as the wind-loading of bridges and buildings.

When a fluid-filled Tibetan bowl is rubbed, the slight changes in the bowl's shape disturb the surface at the water's edge, generating waves. Moreover, when these changes are sufficiently large, the waves break, leading to the ejection of droplets.

The new findings could benefit processes such as fuel injectors and perfume sprays where droplet generation plays an important role.

The high-speed videos allowed the researchers, from Université de Liège and the Massachusetts Institute of Technology, to quantify how the droplets were formed, ejected, accelerated, and bounced on the surface of the fluid.

A similar phenomenon exists when rubbing the edge of a wine glass, which inspired the design of the glass harmonica by Benjamin Franklin. However, the Tibetan singing bowl is easier to excite than the wine glass, since its resonant frequency is much smaller.

In order to generate the waves and resultant droplets, a loudspeaker was set up adjacent to the bowls, which emitted sound at specific frequencies. Once the sound hit the resonant frequency of the bowl—a sound wave vibrating in phase with the natural vibration of the bowl—the waves would be generated.

A high speed camera was used to capture images of the , from which measurements could be taken.

Senior author Professor John Bush said, "Although our system represents an example of fluid-solid interactions, it was motivated more by curiosity than engineering applications.

"We are satisfied with the results of our investigation, which we feel has elucidated the basic physics of the system. Nevertheless, one might find further surprises by changing the bowl or fluid properties."

Explore further: Experiment with speeding ions verifies relativistic time dilation to new level of precision

More information: The published version of the paper "Tibetan singing bowls" 2011 Nonlinearity 24 R51-66 will be freely available online from 1 July 2011. It will be available at iopscience.org/non/24/8/R01

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User comments : 13

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FroShow
4.5 / 5 (2) Jul 01, 2011
I've understood the ejection of water droplets to be caused by constructive wave patterns.
When a fluid-filled Tibetan bowl is rubbed, the slight changes in the bowl's shape disturb the surface at the water's edge, generating waves. Moreover, when these changes are sufficiently large, the waves break, leading to the ejection of droplets.

This, however, implies other mechanisms at work (hinting at cavitation).
Does anyone else find this explanation inadequate? Or going against their established beliefs?
(I'm hesitant to accept that the water droplets aren't being caused by constructive wave interference.)
rawa1
3 / 5 (2) Jul 01, 2011
The complete publication with additional vids can be found here. The videos require QT or VLC Player to run.
http://iopscience...01/media
Isaacsname
2 / 5 (1) Jul 01, 2011
Cymatics on Physorg..?

Wow.

KBK
2.7 / 5 (3) Jul 01, 2011
Ultimately, no matter how it is calculated or interpreted, there is an addition of an angular vector or spin to any energetic forms or delta's encountered in the use of these bowls. This is 3 axis in time, and individual calculations on molecular action motion and charge.

The droplets could not form otherwise.

The calculations get astronomical in size and complexity.

This is hydrodynamic function on the molecular level and charge state and separation-etc. The function looked (searched for) for is probably very simple and of a 'near' 2-d nature but an individual molecule to molecule consideration.

Maxwell's original 20 equations in 20 unknowns contained the aspects of asymmetricality (true!) and elasticity (true!).

The truth in the result must revolve around such considerations.

When making HHO (Brown's gas) the new method is to add in 'resonance' to tickle the electrically forced condition or state.

This is directly implied in this experiment here..as a fundamental aspect.

FroShow
not rated yet Jul 01, 2011
@rawa1; thanks, I wouldn't have looked at the article without your gentle nudge. Apparently I misinterpreted the physorg article and now my original beliefs remain intact (even strengthened!)

Word of the day: Cymatics. Now looking for an opportunity to use it...

@KBK; Please dumb it down for us more laymen-like. Is there an idea you're trying to convey? Are you answering an implied question? Trust me, I'd understand if you're just flaunting your knowledge. If so, help me understand what's gained by doing so.
Isaacsname
4 / 5 (1) Jul 02, 2011
@rawa1; thanks, I wouldn't have looked at the article without your gentle nudge. Apparently I misinterpreted the physorg article and now my original beliefs remain intact (even strengthened!)

Word of the day: Cymatics. Now looking for an opportunity to use it...

@KBK; Please dumb it down for us more laymen-like. Is there an idea you're trying to convey? Are you answering an implied question? Trust me, I'd understand if you're just flaunting your knowledge. If so, help me understand what's gained by doing so.


Check out this video from the Center for Non-Linear Dynamics @ the U of Texas.

http://www.youtub...jP5d6ulc

2 minutes in is very interesting.

Telekinetic
1 / 5 (5) Jul 02, 2011
@FroShow:
KBK just went out on a limb introducing Brown's Gas for the first time on this forum despite the jackals. Brown's gas has nearly miraculous properties , like welding dissimilar materials together or neutralizing radioactive material. Way to go!
Isaacsname
not rated yet Jul 02, 2011
I wanted to link this one too, it's similar to what is described in the article above.

http://www.youtub...=related
FroShow
5 / 5 (1) Jul 02, 2011
I just did a google search on Brown's Gas. Amazing the things people will believe. Somehow I'm not surprised I've never heard of it before. (Probably because most snake oil salesmen died out a long time ago.)
Telekinetic
1 / 5 (7) Jul 02, 2011
Tsk, tsk, FroShow. Is that how you make up your mind because it conflicts with your school textbook? Science is filled with anomalies/surprises that challenge pre-existing notions from the nature of a dimensional universe/multiverse to new and revolutionary forms of energy generation. The jackals find safety in numbers like a mob, but real investigators ignore the prevailing skepticism and investigate. Quantum entanglement, for example, was derided at first even by Einstein, and now what? Snake oil?
FroShow
5 / 5 (1) Jul 02, 2011
@Telekinetic, it appears that you've made some seriously false assumptions regarding my comments and chose to follow it up with inflammatory remarks. This is not the place for you trolls.
Telekinetic
1 / 5 (5) Jul 02, 2011
@FroShow:
Here is the Private message you sent to me 1 hr.-6 mins. ago; "I suggest you yourself do some reading into Brown's Gas and try to find any sources that can substantiate the claims surrounding it. Preferably any sources that do not profit directly from its sale, which shouldn't be hard, seeing as how it's been around since 1800."
Now it seems a bit peculiar to send me a PM with a reasonable tone to it, but publicly take a
hostile stance in response to my post. Are you looking for the support of the other posters knowing that they will lean toward and defend your position? That's a bit cowardly, don't you think?. It's ironic, too, we're exchanging barbs when the subject is about the most peaceful people on earth, the Tibetans. I responded to your harsh dismissal with harshness, but imagine a witness to a crime, and no one believes him. Just imagine my frustration, having witnessed not crime but events that defy what science has decreed unshakeable. I didn't mean to offend you
FroShow
5 / 5 (1) Jul 02, 2011
This is why I PM'd you and offered opportunity for discussion there. Your latest post is a perfect example of what trolls do.