Cavitation and electrolysis

Yes, I did some research on flat plate with nucleating pits up to 1000 PSI.

The object was to make steam with electricity and to study the heat transfer efficiency of various nucleating surfaces.

Plain stainless steel soon was covered by a sheet of steam and went red hot (we used platinum strips after we got sick of stainless steel ones burning in two).

The object was to find the max rate. We stirred it, made tiny laser pit and tiny teflon zones to force nucleation into preferred zones so that heating would take place in adjacent zones that would not form bubbles (which insulated the surface like a foam)

We found high pressure cavitation collapses did damage stainless. Platinum was more ductile and got a slight stippling. I assume iron would also be damaged. In fact cavitation in boilers is dealt with quite well in the literature

You have forgotten that elelctricity is lazy just like H2O so it will seek a ground in milliseconds or less.

the only voltage gradient was along the strip, which was a good conductor, electrolysis was minimal as we drove with high current. The strip was pretty much a short and we had to use a special low voltage transformer.

"Cavitation produces temperatures as hot as the surface of the sun, in addition to extreme pressures even at atmospheric pressure. Add electrolytic splitting of hydrogen, and we could possibly achieve an over-unity device (fusion), as the freed hygrogen is compressed when the cavity implodes"

The only problem is that fusion doesn't occur at the surface of the Sun. The fusion only happens in the core of the sun where temperatures and pressures are much higher.

So the fuel creates its own container?

Not only dose the fuel create its own container but it triggers the initial reaction, keeps it supplied with a steady flow of raw materials, gets rid of the waste and regulates the whole shebang. Pretty neat eh, and to think its been doing it for billions of years and we have trouble getting it to work for a few seconds.

There were some news articles in the paper several years ago about "cold fusion" which was essential air bubbles in water imploading. I don't know what happened to those "threads" it was probably considered as junk science, however of course it is not it may be something that just can't be used yet.

The "cold-fusion" group did not propose any theory - they stated themselves as surprised by the apparent change in radiation levels as the rest of us. In the end, the increases in measured radiation were traced to temperature changes in the radiation counters.

It's an object lesson in one of the ways science should progress - the identification and correction of false results.

On the subject of fusion itself, a high concentration of heavy-Hydrogen species is extremely desirable - and you certainly wouldn't want any Oxygen atoms getting in the way. The other thing that is worth mentioning is that the conversion rates in the sun are very low. So we need to use a more fusible feedstock than is present in the sun, as well as maintaining the same sort of temperatures and pressures as occur near its core. Quite a challenge. (I'm sometimes glad I didn't take up this area of work, as I rather like to see an end product, and doubt I will live long enough)

Fyz

Hi,

this is a very intersting idea.

What I do know about it:

Cavitation needs negative pressure, so cavitation at high pressure is normally suppressed so the necessity of very high intensity pressure waves (ultrasonic or sonic) is clear.

Cavitation is producing ultrahigh pressure spikes at the moment when the gas bubbles reach the final stage of collapse. It is not clear which temperatures and pressures are really reached as the blue light emitted is limited in the UV where water is absorbing. And if temperature is calculated by this wavelength as a pure temperature emitter then a temperature of 28oooK is resulting. Nobody knows how high the temperature is in reality and why it is necessary to have some air or argon in dissolved in the water. I suppose that may be these act as dampers and if not existing the temperature may be so high that the "light" that would be x-rays is absorbed by the water.

Passing a high current through water is not possible in the electrolytic mode. High power will produce arcing and this will give rise to a plasma channel being small in diameter as compressed by the current and its own magnetic field. Any high pressure will inhibit arcing to a certain degree unless the voltage is high enough.

If the wavelengths are matched of the sonic wave and a of a high frequency electromagnetic wave this sonic wave would be 1.5MHz at 1 mm wavelength and the electromagnetic wave with 1 mm wavelength would be 200 GHz (?).

So I think only short (nano to picoseconds) pulses of high current may support to rise the energy in the cavitation bubbles: get a high intensity ultrasonic system at some MHz and add synchronised high voltage high current pulses. Rise the static pressure to a level when the cavitation bubble is still existing. With this system there would be (I suppose) a much higher energy in the collapse of the bubble.

What to test with such a system is another point of discussion - I don't know.

Christmas greetings from

RHABE

Thanks,Rhabe, for a more direct answer to the heart of my question, which was regarding the possiblilty of splitting Hydrogen and oxygen with electricity, and using the high temperature and pressure of cavitation to recombine them.

I realized that very high-power source of a pressure wave would be nescessary, and the resultant temperature and pressure would be much higher than at atmoshpheric pressure.The theory was to drive the temperatures and pressures upward as much as possible.

I know the Japanese have a high pressure chamber where they test submersibles that can crush 1 inch thick steel spheres with air pressure.Something of this pressure range is what I had in mind.

Do you know of anyone doing research in this area?

Merry Christmas to you, as well, Rhabe, and may all your days be filled with an increase in wisdom and happiness.

Hello HiTekRedNek,
As I read your question, the objective appeared to be to achieve some kind of energy gain (which would need fusion, and so I think I've shown this to be improbable). Was there another agenda, or was it really a matter of curiosity (no bad thing, and nicely answered by RHABE) with the idea of fusion as a (to me distracting) wrapper?
Fyz

This has nothing to do with the capitation that HiTeckRedNek was proposing but while we are on the subject of nuclear fusion I thought I would mention it.

While the process scientists and engineers are attempting to get to work economically is a fusion process and the process that powers is also a fusion process the two are not identical. The difference is that the process that is being attempted her on earth is the fusion of two deuterium nuclei to form a helium nucleus while the process that takes place deep within the sun is the fusion of four hydrogen nuclei to form a single helium nucleus. I believe the reason for using deuterium is that it is far easier to push two positive/neutral pairs together than four positive charges.

Now I am not well versed on nuclear physics and the sub nucleic particles that make up the protons and neutrons. However I understand the process of proton to neutron conversion takes place in the nucleus of an atom all the time and is caused by neutrons and protons passing mesons back and forward between them. Somebody else might be kind enough enlighten us on the details of how the sun forces two of the protons too turn into neutrons and how much energy is involved in the process.

The description you give is essentially correct. The result is that the conversion takes place only when four hydrogen atoms collide with sufficient energy, and all other conditions are favourable. This is (fortunately) a very rare event (less than once per ten-billion years for any Hydrogen atom), otherwise the rate of heat generation would lead to a much larger sun than we have at present, and also a far shorter life.

Returning to why we need a different fuel from the sun: for fusion power-stations to be a viable, we need a reasonably proportion of the fuel to be converted in a time that is short compared with the life of the power-station. At the moment, the requirement is even more stringent than that, as it appears that we need to use small volumes if the overall power is to be kept at a tractable level. The result is that we would need either to have temperatures and pressures that vastly exceed those at the centre of the sun, or to use a more tractable fuel.

I hope that all makes sense.

Fyz

Compared to the human body's thermal output, on a pound-for-pound basis, how does the sun rate insofar as thermal energy output?

humans who massed as much as the sun would put out a lot more heat as they all metabolize. The reacting core of the sun is about .2 radii, as per this reference, and other data

http://en.wikipedia.org/wiki/Solar_core

That's an interesting take on things.
The following data on power output is derived from Wikipedia - there could be some numerical errors in the calculations:

The Sun's thermal output is about 3.8E26-W, and its mass is about 2E30-kg.

So 60kg of Sun would generate 14-mW, compared with ~100-W average for a human. So the power/mass from the Sun is only 0.00014 times that of a human.

On the other hand, the Energy output from a human is (say) 70-years'-worth, from the Sun is 10-billion years'-worth, so the Energy/mass of the sun is about 2300x that of a human body.

But remember that, in this respect, the human body is only the furnace for about 2-kG of food per day, so the actual energy-mass ratio is more like 20-million to one.

Notes:
The numbers are relative to the entire mass of the sun. The core in which reaction takes place is only about 10% of that - and (again according to Wikipedia's calculations of the Sun's expected life) not much mixing is expected in the 10-billion year life of the sun (someone please tell me if this is wrong - this is not my direct area of expertise).
In addition, the reaction in the Sun will not proceed to completion, because it will slow down as the proportion of Helium increases (I do not know what the end-point will be).

I knew how the answer would come out, but I just wanted to illustrate the unrealized power of humankind if we alll united together.Multiply 70 years times(say) a billion people and the numbers are amazing.And unlike a star, our mental energies can be focused on an objective, and multiplied by our technologies.If we could only focus.

(exit 0)

HTRN

The statement below this one is true.

The statement above this one is false.

Which forum do you think you have joined?

N.B. The only interesting thing I could ever find about the pair of statements is that only one of the four possible versions has a unique and consistent meaning.

Dear Sir,

I am a research associate at IIT Roorkee India. My work is on cavitation erosion of modified metal surfaces.

I would like to hear more from you if you also have an exposure in this subject. My project is funded and is on begining stage so gund can be directed to any suitable direction.

Your comment shall be appreciable.

Ajay Bhargava

+911334286612