Sound wave energy transfer to heat water?

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SUMMARY

The discussion centers on the challenge of calculating the energy transfer from sound waves to heat in water. Participants emphasize that deriving a specific equation for this relationship is complex and not readily available in standard physics resources. Instead, they recommend conducting experiments to measure temperature changes in water when exposed to sound waves, while also considering the energy output of the sound source. The conversation highlights the impracticality of using sound energy for heating water efficiently, with anecdotal evidence suggesting that significant sound energy is required to achieve minimal heating.

PREREQUISITES
  • Understanding of basic thermodynamics, specifically heat transfer principles.
  • Familiarity with sound wave properties and energy calculations.
  • Knowledge of experimental measurement techniques for temperature changes.
  • Basic principles of acoustics, particularly related to high-intensity focused ultrasound.
NEXT STEPS
  • Research "thermodynamic calculations for heating water" to understand energy requirements.
  • Explore "high intensity focused ultrasound" for insights into sound energy applications.
  • Investigate experimental methods for measuring sound energy transfer to liquids.
  • Study the relationship between sound intensity and energy output in various environments.
USEFUL FOR

Students and professionals in physics and engineering, experimental researchers, and anyone interested in the practical applications of sound energy in heating processes.

Necessity
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I was just wondering if anyone has any idea on how I would go about working this out. I have performed the experiments at home, placing a container of water on top of a speaker and then playing a high frequency and high dB sound through them, however, I can not find any equations online or in my college textbooks which describe the calculations required to find the energy given off in a sound wave.

In a nutshell, I'm specifically after some sort of equation which describes the relationship between sound waves and heat transfer.

Any help appreciated :)

Cheers
 
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Good luck.

This is why people spend yrs getting degrees in Physics or Engineering. To solve such a problem you need to apply the basic principles and derive the relationships involved.

For your case there is NO way go come up with, from first principles the fraction of sound energy which enters the water and causes a heat gain.

It is trivial to compute the energy required to increase the temperature of a known mass of water a known amount. Measure your temperature increase, compute the energy put in. Then measure the amount of energy produced by your amp. The difference will be the amount of energy lost to the surroundings.
 
Sorry, I wasn't actually asking for someone to create a formula for me, but rather, point me in the direction to where someone may have performed the same experiment and done the maths already.

There is a way of doing it as there is a fact I've found on the internet before that says:

"If you yelled for 8 years, 7 months and 6 days you would have produced enough sound energy to heat one cup of coffee."
http://my.telegraph.co.uk/diseverything/blog/2008/09/07/some_crazy_facts

I can't find anything further on that fact though :(
 
It should not be difficult to find something about the energy content of a sound wave. But, as I said above that does NOT tell you how much of that energy is transferred to your water container. There is not going to be a canned equation which tells you that. Your best bet is experimental. IE measure it.
 
Look up "high intensity focused ultrasound". That may have some useful information although it is dealing exclusively with frequencies above the audio range.
 
Necessity said:
"If you yelled for 8 years, 7 months and 6 days you would have produced enough sound energy to heat one cup of coffee."
http://my.telegraph.co.uk/diseverything/blog/2008/09/07/some_crazy_facts

That alone is enough for a preliminary calculation.

Even if you had a speaker's volume turned up to 10 times the power of a person yelling, it would still take nearly a year (10 months) to heat a cup of coffee.

And it goes without saying, that cup would have to be extremely well insulated! Yes, insulated well enough that it would not lose any appreciable heat in 10 months. I don't know of any insulation that is that good.

Sounds like an impossible task.
 

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