Sound wave energy transfer to heat water?

AI Thread Summary
The discussion revolves around the challenge of calculating the energy transfer from sound waves to heat in water. The original poster conducted experiments using a speaker and water but found no existing equations to quantify the energy transfer. Participants emphasized that deriving such relationships requires advanced knowledge in physics and engineering principles, noting that there is no straightforward formula for the energy transfer from sound to water. They suggested measuring temperature changes in the water to estimate energy input and losses, while also referencing a fact about sound energy needed to heat a cup of coffee. Ultimately, the consensus is that experimental measurement is the most practical approach to address this question.
Necessity
Messages
2
Reaction score
0
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
 
Science news on Phys.org
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.
 
Thread 'Thermo Hydrodynamic Effect'
Vídeo: The footage was filmed in real time. The rotor takes advantage of the thermal agitation of the water. The agitation is uniform, so the resultant is zero. When the aluminum cylinders containing frozen water are immersed in the water, about 30% of their surface is in contact with the water, and the rest is thermally insulated by styrofoam. This creates an imbalance in the agitation: the cold side of the water "shrinks," so that the hot side pushes the cylinders toward the cold...
Back
Top