Plasma electrolysis at lower voltages

Quote from Stevenson

https://www.researchgate.net/p…d_engineering-An_overview

Working link: https://www.researchgate.net/p…d_engineering-An_overview

Quote from Stevenson

[...] If this theory is true, it should be possible to get electrolytic plasma by applying a relatively low voltage to deionised water (less than 50V, but dependent on the cell geometry) and then by adding some sparkling water!

Perhaps what you suggest could be more easily reproducible with ultrasonics? I have thought for some time that externally producing cavitation bubbles could make the plasma/sparking process easier to start—at least when they are generated on the cathode—but I haven't got anything yet on this regard to test.

EDIT: on a loosely related note, it turns out that reproducing the operation of the Cosmic Ray Finder program is not complex using Python and the OpenCV library. Only a few lines of code are needed for basic operation. It looks like I'm using the camera differently than that program does and the camera is heating up less and has better image quality.

Here are brief examples of the underlying principles:

https://medium.com/@rndayala/i…ms-in-opencv-40ee5969a3b7

https://subscription.packtpub.…ec28/accessing-the-webcam

To detect cosmic ray events you would read the webcam continuously and calculate the image histogram similarly to what is done in the link above, and select images that have more than a predetermined amount of pixels above a certain threshold value. Operation is fast and compared to the Russian program it uses less resources.

Today I made a few other tests, again with 10% HCl electrolyte solution of low-grade purity using a 0.3 mm Ni wire. I added a partial enclosure in the form of a plastic tube (syringe) to avoid the emission of dust and electrolyte droplets into the environment. It allowed longer testing times without strong bleach or chlorine odors, although still not as much as with alkaline electrolyte. The acidic electrolyte in these tests tends to heat up quite rapidly and evaporation (and loss of Cl from the solution?) is an issue. The anode was a large copper bracket with two cupronickel coins in electrical contact with it.

I don't think I showed the changes with voltage in detail before. The video here starts with a relatively large dendritic deposition of Cu-CuNi on the cathode, at about 40–41V. At this voltage the tips of the dendrites become incandescent. As voltage is increased, the plasma at the tips turns blue and by increasing it further, the dendrites eventually get destroyed and the reaction transitions to a standard-looking cathodic glow plasma with bright dots fixed in place on the wire surface, possibly where nanotips exist. Voltage is increased up to about 72V, where the wire is homogeneously covered by a blue plasma.

Occasionally voltage is lowered again to 40V, where dendrites can grow again.

Electromagnetic emission appears to be the strongest when the wire is in a thin state and 'regular' plasma electrolysis takes place. If dendrites are allowed to grow and stabilize up to higher voltage levels (by increasing voltage slowly), not as much EMI gets generated.

I put the webcam close to the jar, but it didn't get damaged by the EMI, somewhat disappointingly

I did not observe again any clear increase due to the testing, but I did not allow the webcam (CMOS sensor) to get too hot.

Quote from Stevenson

You got it! This is the natural evolution of this concept... Ultrasounds are able to generate plasma by themselves (sonoluminescence) under proper conditions, and probably they will facilitate the formation of plasma with an external voltage applied, because of charge separation or micro bubbles. But there is even more: according to recent experiments shown by Bob Greenyer, ultrasounds seem to directly generate EVOs (plasmoids) inside the liquid. If these entities are actual charge clusters and not only an hydrodynamic analogue, many interesting things may happen by their interaction with an electric or magnetic field... It is an entire new territory to explore.

An issue is that ordinary sparkling (carbonated) water will not have that many CO2 bubbles available in the first place, and it will even be more conducting than plain/tap water due to the dissolved salts (natural or artificially added) giving effervescence. So, to test the idea, ultrasonic cavitation seems the most reliable and reproducible choice.

It does not seem like it would be too difficult to test for people with already the ultrasonic equipment at disposal, but for a plasma to be initiated electrolytically I think one would still need either a large electrolyte concentration or sufficiently high voltages.

Sonoluminescence from isolated cavitating bubbles is likely to involve different mechanisms than electrolytic plasma, in any case. The conditions needed for obtaining the latter seem significantly different; bubbles alone are not enough, and plasma generation does not seem to be a sort of resonating phenomenon as with sonoluminescence (if I understand its general idea correctly).

Quote from Stevenson

Yes, the algorithm is quite simple. The only thing to consider is using the RAW images and not the compressed ones (usually webcams provide JPEG or MPEG streams that remove most of the information, the uncompressed images are available at a lower rates).

I noticed this addition only now. The Cosmic Ray Finder application apparently uses MJPG with my webcam, which caused sometimes noticeable block compression artifacts. By default it seems that OpenCV uses instead YUY2, which brings better quality. In both cases at least with my webcam the maximum is 10 fps. The codec can also be forced as seen in the example given here: https://github.com/opencv/opencv/issues/7013

In response to suggestions (e.g. Matsumoto) of plasma balls detaching from the cathode I made a quick test.

What is going on: The electrolyte is a moderately concentrated K2CO3+KOH solution dirtied by iron oxide impurities. Voltage is about 69V. The cathode is a 1 mm tungsten needle with a sharp tip immersed for about 1–2 mm in the electrolyte. There are two anodes: one composed of two 10mm-thick steel brackets and a 0.3 mm tungsten wire.

The test starts with cathodic plasma already ongoing with the large steel anode and the 1 mm tungsten needle. I then submerge the 0.3 mm tungsten wire anode and remove the steel anode. The reaction at the cathode keeps going at a lower rate and nothing of interest occurs at the anode regardless of the distance. I try switching anodes a few times and at times both are immersed.

The most interesting observation is that once the cathodic plasma is initiated, the wire anode does not need to have a large immersed surface area. I could not observe plasma balls (or similar) detaching from the cathode and going to the thin anode, though. If different testing conditions to see this are needed, please advise.

EDIT: here is one source for that from the attached PDF document (around page 81), although it is not here that the use of two anodes is mentioned.

I do easily get "separated sparks" with titanium wire as the cathode, but that's due to it (or the hydride formed) igniting with temperature, and generally the process is destructive for the wire. Perhaps other hydride-forming metals (e.g. Pd) just emit sparks at a low rate under similar conditions, as they get eroded.

The dust on the bottom of the jar is iron oxide powder.

EDIT: to clarify, titanium also reacts (combusts) similarly by excessive joule heating in the atmosphere.

EDIT: also clarified that I meant the "separated sparks" mentioned in the previously posted excerpt relatively to figure 4. I have otherwise never observed these features in the tests except possibly from excess K2CO3 electrolyte accumulated on the cathode dissociating to potassium metal and reacting violently with water.

Curbina

The following papers (1992–1993) discuss those experiments with Pt "pin" and Cu plate, but I don't understand why in the first paper the pin is referred to as an anode since AC was used. Since anodic plasma needs considerably higher voltages than cathodic plasma, it is possible that a plasma only appeared when polarity was negative (I personally never tried AC, though, so I could be wrong).

https://doi.org/10.13182/FST93-A30209

https://doi.org/10.13182/FST93-A30214

In the experiments described in the Journal of New Energy issue I uploaded earlier, DC was used instead.

This more recent (from year 2000) brief open-access paper again from Takaaki Matsumoto seems more relevant (low-voltage discharges/plasma electrolysis using DC and thin cathodes) to this thread, but to be honest the 150 keV claim sounds in-credible. It refers to the same tests described in the Journal of New Energy 1996 1-4 issue linked above:

https://www.osti.gov/etdeweb/servlets/purl/20133163

Quote

Feasibility of X-ray laser by Underwater Spark Discharges

Abstract: The method of Underwater Spark Discharges(USD) is one of the most effective ways for generating extremely compressed atomic clusters (called itonic clusters or micro Ball Lightning(BL)). It is also associated with energetic X-rays, which are caused by the break up of the itonic electrons. Despite of low voltage discharges of about 50 V, the high energy X-rays up to 150 keV can be generated. This paper proposed two methods of generating X-ray laser by using micro BL: (1) micro BL on surfaces of regularly arrayed wire cathodes and (2) gas of micro BL generated by USD. (author)

Here it is mentioned that the X-Rays are due to the break up of the clusters (Bremsstrahlung?).

But earlier on (JNE) it was suggested this was just electromagnetic noise:

Why in-credible? 150 keV x-rays would pass through many meters of air and several centimeters through glass and water, and I think I would have felt them if they are routinely emitted in the experiments.

Also see: X-Ray attenuation & absorption calculator (gsi.de)

Curbina

If they are X-rays, I think they are unlikely to have been emitted directly by the reaction. The signal at 70V, if you carefully check out the different vertical scales (counts/min, counts/5 min, counts/30m), was about 2000 times larger than background. Such strong signal should be easily detected by most radiation detectors.

It's still possible that the signal was generated inside the detector itself while still not necessarily being electromagnetic interference, and so that it appeared larger than it actually was. A similar principle is used with Leif Holmlid's "muon detector", where the muons generate electron-positron showers directly inside and in front of the window of the "blind" photomultiplier tube (PMT) used for detection (see here). No scintillation crystal is normally used, just aluminium foil in its place.

If this was the case, it would mean that an ordinary scintillation detector as used by Matsumoto would be enough to detect the 'muons', although making sure that it really isn't just EMI under these these conditions would be a challenge.

Using again an alkaline electrolyte cell, I tried retrieving the average strength of the signal over time at a frequency where the difference between the on/off state was high. I used a standard RTL-SDR USB adapter (radio receiver), a ready-made utility (rtl_tcp from the 'osmocom' package) to retrieve the samples and custom-made code in Python to process them.

Some related links:

• https://hz.tools/rtl_tcp/
• https://ftp.osmocom.org/binaries/windows/rtl-sdr/
• https://osmocom.org/projects/rtl-sdr/wiki/Rtl-sdr#rtl-sdr
• http://whiteboard.ping.se/SDR/IQ

The average strength is calculated roughly every second with samples retrieved at a rate of 256 kHz. The peak value over those samples is also retrieved. Below is the graph from a brief period of testing under various conditions. The low flat areas are during off conditions.

It appears that many dynamically changing variables affect it, and the EMI might not necessarily always increase when increasing applied voltage. The onset of plasma appearance can be stronger in magnitude, to only drop substantially when a visible plasma appears (left portion of the graph).

After a plasma is visible and voltage high, The signal at times slowly increases under stationary input conditions, presumably from the electrolyte heating up and its concentration increasing near the cathode. Sometimes instead it suddenly drops in response to spontaneous changes in the reaction (middle portion of the graph).

The signal can also be affected by walking in the same room, which presumably causes the generated emissions to bounce differently to the antenna, which seemed unusual for a ~82 MHz frequency. The line-of-sight path between the antenna and the cell is unimpeded (not shown here).

Both with an acidic and alkaline electrolyte it does not seem that a large cathode helps, even if the reaction looks stronger and power put into the cell substantially increases (from prior testing—not shown here).

I also tried retrieving data at a high rate (about 2MHz) and as I pointed out in a different thread, the noise appears to have a 1/f character. With a logarithmic scale for both axes in the frequency spectrum, a more or less straight line is obtained.

What this implies exactly, I'm not sure but it's probably not too unexpected. More information here: 1/f noise - Scholarpedia.

Curbina

I don't have the suitable Peltier coolers for that.

I'm aware that Sveinn Ólafsson and Sindre Zeiner-Gundersen have used a cloud chamber in some of their experiments.

Curbina

I think it would be simpler to get suitable high-power Peltier cells (+ cooler + fan + all the rest) than dry ice. I am just doubtful that much will be seen besides a [high] background signal, since not much else than that was seen so far with a CMOS sensor (often used for detecting cosmic rays) or with a Geiger detector I previously had.

This and the inconvenience of not being able to properly log or quantify the observed traces, as well the need of periodically refilling the device with alcohol make me not very inclined to put funds on building one such DIY cloud chambers.