Thanks for your thoughts on how you envision the mechanism for cavitation with regards to the production of excess heat, fabrice DAVID , I like the way you separate the cases for ionic liquids.

I suspect that you are on a very good trail.

Quote from Alan Smith

Method of generating energy by acoustically induced cavitation fusion and reactor therefor

Abstract

Two different cavitation fusion reactors (CFR's) are disclosed. Each comprises a chamber containing a liquid (host) metal such as lithium or an alloy thereof. Acoustical horns in the chamber walls operate to vary the ambient pressure in the liquid metal, creating therein small bubbles which are caused to grow to maximum sizes and then collapse violently in two steps. In the first stage the bubble contents remain at the temperature of the host liquid, but in the second stage the increasing speed of collapse causes an adiabatic compression of the bubble contents, and of the thin shell of liquid surrounding the bubble. Application of a positive pressure on the bubble accelerates this adiabatic stage, and causes the bubble to contract to smaller radius, thus increasing maximum temperatures and pressures reached within the bubble. At or near its minimum radius the bubble generates a very intense shock wave, creating high pressures and temperatures in the host liquid. These extremely high pressures and temperatures occur both within the bubbles and in the host liquid, and cause hydrogen isotopes in the bubbles and liquid to undergo thermonuclear reactions. In one type of CFR the thermonuclear reaction is generated by cavitation within the liquid metal itself, and in the other type the reaction takes place primarily within the bubbles. The fusion reactions generate energy that is absorbed as heat by the liquid metal, and this heat is removed from the liquid by conduction through the acoustical horns to an external heat exchanger, without any pumping of the liquid metal.

Images (2)

Classifications

G21B3/00 Low temperature nuclear fusion reactors, e.g. alleged cold fusion reactors View 2 more classifications

https://patents.google.com/patent/US4333796A/en

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Great find Alan Smith , I think the “brute force” for smashing atoms is not what cavitation really brings to the table, but it seems in 1982 it was believed to be. I wonder whatever happened to this IP during its period of exclusivity, if anyone ever invested on it.

After reading the patent and finding out more about Dr. Flynn, and while admitting that I have since long left behind the idea that the anomalies (both energetic and elemental) observed in cavitation experiments have anything to do with the “smashing of atoms together” approach of hot fusion, I also have to comment that I had thought that the sonofusion and ensuing controversy about the validity of the idea had been first put forward by Taleyarkhan in the 2000’s, so I have been very surprised to realize that it had been proposed and even patented in 1982 by Hugh G. Flynn, who now I know, was a prominent author and explored cavitation and ultrasonic cavitation in depth (some consider his books to be the seminal work of ultrasound and he was one of the first working in lithotripsy of kidney stones). To think that he died in 1997, and that the patent expired in 1999, and even tho it seems that, in general terms, his work in this concept seems to have went largely unnoticed, is surreal.

This paper about Flynn's work published after his passing is interesting.

https://asa.scitation.org/doi/10.1121/1.422386 (Physics of acoustic cavitation in liquids: H. G. Flynn’s review 35 years later The Journal of the Acoustical Society of America 103, 2970 (1998); open access)

Quote from Ahlfors

Publication Number WO/2021/072152

Publication Date 15.04.2021

[MIT] SYNCHRONOUS EXCITATION OF MULTIPLE SHOCK WAVES FOR FUSION

Very interesting, achieving coherence once again is regarded as key.

Quote from fabrice DAVID

Thank you for this information, I did not remember that the patent was so old. But I had seen the photo of the General Fusion reactor in Science & Vie (The French Naukha y Jizhii, it's my favorite science journal)

But a kilogram of NaKLi at 40 ° C with tweeters glued around the spherical container (two stainless steel bowls from IKEA) is easier to make than a reactor with giant pistons which will be very difficult to synchronize. (And much cheaper)

I love cheap experiments that you can do on the corner of a lab bench, but which change the world.

Here, while I am writing to you, I have the hardcover volume of the Bulletin of La Société Chimique De France in my library in front of me. I cannot resist the temptation to show you an illustration of the article by my teacher Prof. Marius Chemla regarding the isotopic separation of lithium. The Americans were using thermal gradient tubes 15 meters high in a huge factory, and with a device that stood on a laboratory bench, he brought the French prime minister the first gram of pure lithium 6.

So I think it is perhaps possible to do the same thing with fusion.

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Very inspiring, I also think that a principle that can be proven by simple means is more elegant in the long term.

Your account made me recall that the controversial Bob Lazar had a contraption in the ceiling of his house to produce Lithium 6 which he claims is an excellent material to store hydrogen in large amounts as an hydride and just requires a little heat to release the hydrogen. As Lithium 6 is forbidden to be sold to anyone, he had to make that makeshift system that he used to get enough Lithium 6 to use in the hydrogen storage tank to run his famous hydrogen powered Corvette.

Quote from fabrice DAVID

This seems to me very strange. I am a former student of Pr. Marius
Chemla, who discovered the Chemla effect, the best way to make
lithium isotopic enrichment. (He is the little man with brown hairs
beside me and Bill Collis at ICCF 11. He was over 80 at this time.
A great scientist. )

So the lithium enrichment don't need huge amounts of lithium. About
hundred tons for the warhead program, hundred tons for the civil
reactors neutron balance, and the same amount for the submarines, no
more.

(For the warheads, the exact value of the best isotopic and chemical ratio
Li7/Li6/Be/B is classified.)

I don't think that this isotopic enrichment program was sufficient
to produce a big isotopic shift on commercial lithium, since the
« boom » of lithium batteries market. For our
experiments, it is not relevant.

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This comment from fabrice DAVID tells the story Peter