Using Stealth Propulsion for Ocean Travel (MHD Thruster Build) 

Let me know your thoughts down below - I'll be revising this to increase output. For the time being, 3D files can be found on my Patreon site!

Look into halbach array magnet configurations. You can double the field strength inside your thruster by arranging the magnets so that the field is contained entirely within the thruster and the external field is cancelled out.

The force on water is =B*I*L where B is the magnetic flux density, I is the current in the water( between the electrodes), L is the spacing between the electrodes(i.e length of the conducting path), Also current (I=V/R) is voltage(V) by resistance and here the resistance(R) is clearly proportional to the electrode spacing L making R=k*L where k is a proportionality constant. Long story short the force B*I*L becomes B*(V/(k*L))*L that is B*V/k i.e it is independent of the electrode spacing and linear wrt B and V. This should be fine for intuition, but the resistance is also non linear which only complicates things I must also add this, there are two currents now here, one going between the electrodes (I) and the other being the thrust flow itself(i) if you use the same rule for this new current(i) a new force arises opposing the main current (I, between the electrodes), this new force is B*i*c where B again is the magnetic field, i is the flow of water causing thrust and c now is the overall length of the electrode. The direction of this force is ixB that is the cross product of the velocity of charge flow and B(I know it's cXB but that's hard to imagine) and it is opposite to the main current I between the electrodes. This is the back emf in this system where the faster your thrust flow the lesser the current between the electrodes which inturn reduces the thrust force. To put all this mathematically, the thrust force which we saw as F=B*V/k should be replaced by F=B*(V-a*f)/k where 'a' is back emf constant, f is the thrust flow rate showing that flow rate will counter itself

I think the electrode spacing test is misleading you here. You are measuring flow velocity, but that is not your actual goal, thrust is. Thust means mass flow, which is proportional to cross section and velocity. If your velocity stays constant, but your cross section increases, it means more thrust. If you are testing with a constant voltage source, more distant electrodes will mean lower current thus lower power. You also likely have a larger flow cross section with more electrode spacing, so combine that with lower power, that means wider spacing should actually be an effective way to improve your thrust/watt.

Good work, particularly the parametric testing. The reason the electrode spacing didn't matter was that you did not account for the return path of the magnetic field. The result is a counter magnetic field on the outer fringes closest to the plates creating turbulence and drag. You can see this at timestamp 4:28 on the upper plate on the right. It is even present during the 3cm test at timestamp 4:42. Wider spacing needs a wider magnetic field, at least as wide as the plates are. The second thing is that if you use a magnetic core, such as steel, laminated iron, or ferrite, to complete the return path, your magnetic field in the chamber will be higher still, leading to higher chamber medium velocity. PM me if you need more details. :)

All this is fascinating and all, but what has me in awe is the sheer believe that he will not drill into his tempered glass table 😲

A laminar flow straightener behind the flow with something to increase the Reynold's number would likely increase efficiency. Break the boundary layer at the electrodes and then columnate the fluid again to get an even thrust across the nozzle. While water is rather sticky it is also viscous enough to react nicely to boundary layer separators especially since it's practically incompressible so there's little spring effect.

NICE! May closer spacing doesn't increase current draw because of some factors like bubbles on the metal surface could limit the draw. Good engine though, beside the side effect of electrocuting planktons!

I think this is really cool. A nice upgrade would be a hexagonal configuration and you could run it like a bldc. It could make a water screw improving velocity further

Drag is going to be the limiting factor in this thruster. On top of the thruster drag there will be a vessel drag component as well. So the lengh making faster flow is great for a practical display, but optimizing the design would require that drag be the factor used to determine field strength and voltage inputs. For any given thruster size, it will have a maximum velocity in the water due to it's drag. Practically speaking this would mean that the nozzle used in this video would be a limiting factor of volume because the fluid cannot be compressed. Therefore the nozzle increases drag, and limits volume. I would imagine that a thr

This was super interesting, thanks for doing it. I had a scan through the comments and didn't find any of these points: 1) The electrode spacing doesn't change the deltaV, but it might increase the thrust because more volume is being pushed. It would be worth to measure the thrust (hang your device by a string and measure the string angle/displacement). Ultimately thrust force is what you were looking for, so that might be a better metric than DeltaV. 2) Does the current go down with increased electrode spacing? Coupled with point 1, more spacing could be even more efficient (or maybe you did test this and I missed it...) 3) When increasing the voltage, does the current increase linearly or instead have inflection point(s)? I would expect at certain voltages the chemical process (electrolysis) to change as you reach the threshold voltage for new electrolytic reactions. Although you might get less thrust from lower voltage, you might find it more efficient 4) How does the thrust change if there's already an input velocity. I suspect it doesn't (if you can rule out the drag of your vessel).

You can significantly increase the magnetic field strength by using a closed magnetic circuit instead of an open one. You can also use Halbach array

It's been a while, but the novel of the Hunt for Red October the RO used ducted turbines deep in the hull. It was called a "caterpillar" because it had many turbines spinning pushing the water. IIRC it did use magnets to move the turbines (instead of prop shafts and motors).

Fun idea! As some other said, I think that smaller opening at the back might decrease the thrust rather than increase it. It does increase velocity of the water coming out but total thrust is dependent on the flow of water as well and the increased velocity most likely doesn't make up for the lost flow. This gets even more a problem if used to power a boat - because the movement forward of the boat will cause the water to also enter the inlet at some speed relative to the unit and get accelerated to even higher speed - which increases the total flow thru the unit by a lot. This will cause that opening to act like a big choke - making the thrust decrease faster with the speed as well. If the channels have the same cross section area thru the whole unit, the water will just enter with some speed and accelerate freely to even higher speed, and continue to produce thrust even when getting up to some speed.

In the book, the Red October actually has impellers in the two shafts for the caterpillar drive. The pressure pulses, and resulting sounds, are how the sonar crew picked it up. In the book, as the story goes, the US toyed with this sort of system but wasn't able to get past the backpressure issue and abandoned it but the Russians made it work. In the movie it was a "magnetohydrodynamic drive" but again that's different than the book.

Your "bias" is pride in quality !! Thank you for your contributions.

One design consideration that you're not considering here is the drag of the thruster. It's fine for this test to have a bulky design since the surrounding water is fairly static, but on a boat once it gets going there comes a point where the bulk will definitely be a hindrance. STRICTLY SPEAKING, a MHD could be built with very little drag by lining the boat's hull length-wise with alternating electrode-magnet strips in the pattern +,N,-,S,+,N,-,S,+,N,-,S,+, ... This would mean that the hull of the boat is almost "wrapped" with an EM field where the electric and magnetic field are intersecting almost perpendicularly at every point thus generating a skin layer of thrust along the entire hull. My hypothesis with this is that the thinner the strips (and hence the more +,N,-,S sets per unit length one has along the crossection) the more efficient the energy transfer will be because the field will be more localised around the boat. Also maybe putting some thought into how the wiring is run to the electrodes might help by orienting the magnetic field their current generates to form additively to the fields of the bar magnets rather than have them be wasted EM emissions.

One suggestion - you really need an iron backer to give the magnetic field lines a place to return that aren't the 'wrong' direction through your water.

have you considered a column of ring magnets in the center of an aluminum tube? Forcing the current to run only through the magnetic fields could have an interesting effect.

Electrolysis, top secret navy propulsion systems !!! And separating the molecular bond between hydrogen and oxygen that are also explosive ... Love the Channel

It would be interesting to see how an electromagnet could be used to vary the thrust.

"To my local scientific supplier, often mistaken for a home improvement store" 😂 So true! The people at my local store have stopped asking if they can help me find something and started asking what I'm working on today. As they know I'm likely bot using something for what it is being marketed as, lol.

Are you concerned about generating chlorine gas with this electrolysis setup? Or are you using something other than NaCl for the salt in the water? I'd be worried about pushing the voltage up with table salt in the water, that could get dangerous.

I would redo your test while considering watts in relation to thrust or mass flow. Also consider lover voltage. Voltage below electrolysis doesn’t waste energy on splitting the molecules into ions so it should be more efficient.

So much stuff on youtube is one offs, watching the iterative design adds so much.

Man, when you put that thing in the ocean and traveled. Wow. This renews my hopes of someday building a balsa, rubber band powered, craft for air travel.

I'm amazed at the thrust you produced on your first attempt! For efficiency, electrode spacing should be your last parameter to test/adjust. I've seen other comments make this point as well. You didn't have enough energy in the system yet to get a measurable result. I understand why you would want to adjust voltage last, but you can definitely maximize your mag flux first before finding the optimal electrode spacing. Two variables to consider when doing this- one obvious one you are already familiar with is arcing, but the other is volume of energized medium. You will hit a point of diminishing returns as you collapse the volume of fluid that can be accelerated between the electrodes. I think this can be somewhat mitigated if you use a staged approach, perhaps with one wider MHD at entry leading down to many narrow MHDs at exit

for electrodes, check out those pool chlorine generators. They are designed for this purpose. You gotta take em apart to get the electrodes. I got mine from someone who did pool maintenance caz every so often they need to be replaced. The ones I got were completely jammed with salt. easy for me. trash for him. The electrode is some kinda vanadium oxide on titanium. I use them ALL the time & they surpass everything by lightyears. Second best non-corroding electrode if you have to buy... is ... titanium. Ti is cheap & the least prone to dissolve.

Hi folks If you want to try this at home, please ensure to do it in a well vented area as it produces flammable hydrogen and also chlorine gas. No reason not to try this though so long as basic safety measures are taken. I'll definitely be trying this myself!

I like how your adds are seamlessly integrated into the video. It's very creative and much less obtrusive

An MHD is used in the Oregon Files books by Clive Cussler. They're about a secret off-the-books outfit that operates from a super advanced ship that's disguised as a tramp steamer. It's propelled by an MHD, however, it's far more advanced and powerful than anything in real life, allowing the ship to move incredibly fast for its size.

Man your channel is more important to me than you know it’s good to see dudes doing good interesting things like this and networking with other interested professionals. Keep playing the game you’re pushing humanity forward

I think that a more narrow gaps leads to increased resistance, in the water flow, that cancels out the increased force applied. Maybe testing with different depths of water would show a difference

This is fascinating I can’t wait to see how you refine and scale up this lovely rig

Try using Pulse Width Modulation (PWM) with a Pulse Repetition Frequency (PRF), it may save on the overall wattage. You may also try and use some low amp high voltage supply. This will allow the water once it's moving to help keep the water flowing even when the voltage is off. Kinda like once you get a tire rolling it doesn't take as much force to keep it going. You may also consider using Idler Plates, they are used in Hydro Gas Generators to keep the water charged while using less electricity. Hope that helps give you some more things to consider and test with. Best Wishes & Blessings. Keith Noneya

Here is some ideas to implement into more research in the design to generate increased thrust in the divice. 1. Conical Intake Design: The idea revolves around shaping the intake structure in a manner reminiscent of a cone. This means that the intake's geometry gradually widens from a pointed tip to a broader base. This design choice has functional implications: the narrower tip corresponds in size to the entry area that accommodates the magnets and electrodes. As you move toward the wider base of the cone, the intake's capacity increases. The tapered nature of the cone encourages fluid or gas to flow more smoothly and efficiently, as the gradual expansion reduces sudden changes in flow patterns that might cause turbulence or inefficiencies. 2. Enhancing Fluid Flow: At the tip of this conical intake, you suggest integrating blade-like contours. These contours serve as strategic features that influence the flow of the fluid or gas entering the device. The intention here is to initiate a spiral-like motion, gently coaxing the fluid or gas to follow a swirling trajectory. This spiral flow pattern carries several benefits. It can aid in efficient mixing of gases, improving combustion in the combustion chamber if applicable. Additionally, a controlled swirling motion could help in preventing stagnation or dead zones within the intake, leading to a more consistent and even distribution of the incoming fluid or gas. 3. Central Conical and Cylindrical Structure: You propose extending the conical design concept to the central part of the device. In this case, you're considering the possibility of shaping the central region into a cylindrical form with a spiraling exit opening. This central cylindrical configuration could be designed to complement the conical intake, maintaining the same fluid dynamics principles. This design evolution, although more complex to engineer, holds the promise of further streamlining the flow patterns within the device, possibly enhancing overall efficiency. 4. Timing Spark Gap Innovation: The innovation of introducing an adjustable timing spark gap within the exit orifice carries intriguing potential. This feature essentially enables the controlled ignition of the mixture of hydrogen and oxygen gases as they exit the device. This ignition could lead to a significant burst of energy, propelling the device forward. However, this dynamic ignition approach comes at the cost of generating noise due to the rapid combustion. To harness this concept effectively, meticulous synchronization is necessary. Adjusting the timing of the spark gap becomes critical, taking into account not only the ignition process but also the counteracting force from the incoming water, creating a harmonious burst of outward propulsion. In summary, your concept involves employing conical shapes throughout the device's intake and central structure to optimize fluid dynamics and gas combustion. Additionally, the inventive introduction of an adjustable timing spark gap introduces a dynamic element that has the potential to significantly enhance the device's propulsive power, albeit at the expense of noise. This amalgamation of design principles seeks to harmonize various factors to achieve the desired efficiency and performance. Cant wait to see more on this.

This is a fun project. I would like to see it propel a kayak for a long distance. It doesn't seem like it can produce enough thrust for a long enough period of time without making one that's too heavy.

This is so cool I hope I can do things like this some day as I am still learning about high voltage and electronics and this channel has been an inspiration for that thank you

ACTUALLY in Hunt For Red October it was not an MHD drive. At least not in the book. It was an impeller design. The film made some remarks pointing towards MHD (Superconductors), though.

Definitely looking forward to seeing this applied

This is so amazing. Thank you for sharing this with us. Using this to advance desalination with no moving parts. So many other places this tech could be used.

I see stuff on this off and on every so often. Its a really cool concept and on small scale can produce some entertaining results. So far however I've never seen anyone able to scale it up to a usable size. The one attempt I heard about (bear in mind this was a decade or more ago i read about this) got a ship up to 15 knots and maxed out there for a lot of energy. They figured out Magnet tec is not there yet. Electronics and Salt water don't mix well (surprise). And it needed a LOT of power.

Probably should be measuring volume of flow instead of just velocity of flow. 3cm vs 5cm, with the same velocity, but 5cm (looks like) has nearly double the total volume. Especially if it allows you to put more magnets next to eachother. More magnets is probably a lot easier than more power in an actual vehicle.

FANTASTIC! A clear design direction for dramatically increased thrust from an electromagnetics engineer: Widen the port aspect ratio (more distance between electrodes, less distance between magnets), and add a magnetic return path between top and bottom magnets. Reasoning: 1. Low to no loss of thrust from widening the gap between electrodes. 2. HIGH gain of thrust from increase in magnetic field strength easily obtainable by moving magnets closer together and adding a magnetic flux return path from top to bottom magnets. A bit like two custom C-clamps wrapping around each side and clamping against the top and bottom magnets, creating a flux return path. Think of each magnet like a "magnetic battery," and the gaps between magnets as resistors. If you want more current (flux) to flow, you can increase the "voltage" (magnet strength), and/or reduce the path resistance (distance between magnets). A flux return path is like a low-resistance solid conductor in an electrical circuit, so the lower "circuit" resistance means the "current" (flux) goes up. Higher flux, higher thrust of your design. Beautiful work. Thanks for sharing it!

Excellent job at communicating a complex process and theory into something easily understood. Way to go!!!

Can you imagine what our ancestors 300 years ago would of thought about today's technology? Salem Witch trials 2.0

The distance between the electrodes mostly applies as a function of ion density/saturation. Since you're ion saturation is fixed then there will be a maximum distance where there will be no added loss with additional distance. To counter this situation you can boost the effectiveness exponentially using alternating current and a matched phase electromagnet. The additional usefulness is compounded by a reduction in erosion effects. If you're going to try it, then definitely use stainless steel electrodes. You can also apply the halbach array concept to the electro magnets to increase performance further

Great video. Was left pondering if you went back to the testing that failed to produce results and retested using the enhancements you already found. Sometimes a factor is limited by other elements and might not be limited after changing other elements in the test article.

I don't know how it is I worked with plasma systems for 4 years and only stumbled across this channel last night... but yeah subscribed.

I worked on MHD projectiles in the 80's, it is a pretty cool technology.

What would be really interesting is to know the effectiveness of this kind of propulsion and how it compares to other types like typical propellers or jets.

If you want to try something, use different shaped exhaust nozzles. I believe (my assumption) that incompressible water doesn't work well with de Laval nozzles, try straight and divergent only. This is something I noticed on jet pumps.

It was given the nickname "Caterpillar" because they used several in series which not only applies thrust but were also optimized for the pre-accelerated input flows. One can take advantage of moving flows by designing the next in series optimized for the higher speeds and advance that by a higher amount.

How awesome! We are definitely getting into a magnet era. Our world will be so different in 30 years from now. 😊

Fascinating! You could use niobium for the electrodes as they are very conductive and won't break down at all. Niobium is used as electrodes in hydrolysis for production of hydrogen gas in the clean energy sector for that reason. It can take very high voltages- I anodise to a variety of colours for jewellery at voltages as high as 120 volts.

I love the idea and concept. Just wondering, have you tested the salt water afterwards? Because of the electricity passing through the water, doesn't it become more chlorinated?

Two major concerns that came to my mind: One, your electrodes and magnets were steadily and rapidly dissolving, especially at higher voltages. Two, those dissolved metals, ions, and oxides may be toxic to the same marine life that this drive is supposed to be protecting.

Umm... The way I remember the story of the Mitsubishi MHD is that the strength didn't really scale well, and despite having massive diesel generators it produced some pitiful amounts of thrust. But it's a nice project :)

There you go girls , length matters, and circumference matters, to increase the velocity of the fluid. It's called magnetism. This is a most informative video and interesting new science to me. Thank you for sharing.

"This is also how a railgun works"... I find that explanation the best hit in the entire movie. If you know how a maglev/rail-gun/gauss-gun/etc. works, you know the basics of this MHD propulsion. Thanks for the hint.

Hey Jay! can you give us any updates on the nuclear fusor you made? :)

Hey! It'd be cool if you included how the thrust compares to other devices of similar class and their counterparts at the end.

Is thrust scaling linearly with voltage? Might be interesting to try the stun gun modules to get that insane spike.

I have come to really like this channels plasma theme. Keep up the great work! You have inspired me to build my first tesla coil. Slayer is going to be my first circuit. Coil is done.

Imagine - using this device on not only on boats of all kinds, but also on cars and maybe even planes and drones. The possibilities are endless.

Very interesting. Thanks for taking one for the team, and performing this experiment. I do think you need to look at what those same 225 watts input, gives you in thrust, from an ordinary electric trolling motor. Also, you might figure out what fraction of a horsepower (hint... a whole horsepower basically equals 746 watts, and is defined as the power required to lift 550lbs at one foot per second.) I am guessing that your device is operating full throttle at about .01hp. Or about 7.46 watts of output power. So your efficiency is roughly 3%, assuming that my eyeball guesstimate of output power is in the ballpark. I am not too surprised that you achieved a positive result. I am also not surprised that it is incredibly inefficient. Since the effect is well known and easily implemented, but nobody is doing it commercially even though an awful lot of people out there are desperate to make money, that it had already been tried a lot, and dismissed as pretty much a failure, in practical terms. Viable ideas have a habit of being turned into commercial success. Everyone has to be that guy who did it first. Rudolf Diesel. George Westinghouse. Thomas Edison. The Wright Brothers. All proved a concept but initially only showed laughable results in terms of efficiency and practicality. But honestly I don't see this as really becoming a thing. And I can tell you positootly that it is NOT silent. You just aren't listening correctly. One thing you might try, is a very fine matrix instead of discrete magnets and electrodes. Think like nanotubes, bundled together. Maybe the electrodes and magnets etched in the manner of modern integrated circuits of high order, such as microprocessors. Maybe at some point of miniaturization, the induced turbulence or something would begin to cause a diminishing returns effect. Who knows? But one thing is for sure, and that is that you are not giving your viewers any hard data on efficiency. Now you probably have a hundred shade tree redneck physicists buying golf cart batteries and magnets, and butchering boats, and dreaming about clean, silent, swift and efficient passage to their favorite bass fishing holes, and winning tournament after tournament against guys sporting 1200hp pro bassing machines. They are gonna be pretty disappointed. The same guys who saw Wile E. Coyote using a fan blowing into a sail to reach potential roadrunner-catching speed, or who thought that he could hook up a really good motor to a really good generator and make them run each other, with energy left over to tap off and use for other stuff. Well, it's not like you encouraged anyone, but you should level with your viewers about the apparent efficiency of your first iteration of this concept.

What is the thrust per Watt ratio of this compared to an electric motor in energy used?

My guess is closer electrode spacing leads to higher E field strength, but proportionately less volume of water between the electrodes to actually be thrusted, so the two things cancel out? Also, presumably there is nothing to stop you using plastic coated electrodes that would never corrode?

Your videos remind me of what TKOR was in its prime, but with more advanced topics. Didn't know I needed that itch scratched in years

Very cool experiment! One side note: using current instead of voltage as a parameter could give a clearer picture of the effect of varying parameters. For example, making the electrodes longer doesn't increase efficiency, but it does allow more current to flow which is actually what causes the increase in thrust/flow.

Could you increase thrust with/by laminar flow??? Either before it gets between the two metal parts or after...

I cross B is what drives the force. Water has constant resistance per length we will say and so you should see an increase of current with a smaller gap. But your gap may be so wide that is acting more as a capacitor than a resistor making the current leakage driven. If I remember from my course though, mhd is voltage driven. If you perform all the maths you end up with the voltage and the pressure rise in the pump being related and independent of gap distance. The pressure rise determines the power and the current is a balancing term.

Really liked the explanation about the use of brass

Awesome creative effort. Humans at their best creatively. Will save a lot of marine life if it ever goes to scale.

You have the smoothest segue into sponsored content of anyone.

This was very cool and interesting. I had never heard of this concept before this. Thanks for sharing this experiment.

I worked in a magnet shop and we would stack magnets sideways to make the magnetic field reach out further and have a more direct area. For instance stack vertical of north on its side and south on the other then put one in the middle of the 4 facing the opposite of the 2 and in the middle has a further gause

This is really cool, and I appreciate the care and attention to detail here! A couple of thoughts on some of the results here (my background is fluid dynamics): the water is pretty shallow in your testing, so that might be somewhat damping out the effects on velocity (although this is only a guess). The flip side is that if your velocities are constant, you might want a wider spacing because that means you're moving more water, which means you'll have higher amounts of thrust for the same water velocity. The parametric testing was cool, and I appreciate it! Have you heard of Box-Behnken design of experiments? It's a way of testing a bunch of parameters together that reduces the total number of experiments and takes into account that parameter A and B might have positive or negative correlations. Thanks again for the video!

Idk how far this can go but I'm here for the ride.

Earning Trust takes time but... I " TRUST" what you say.

I cheer for you, regardless of outcome, you did this well with a great approach. Be proud.

Very nice. For reduced corosion you can use stainless steel 316L, it is used in marine and oil rig instalations. More exotic it is 316L with a coating of titanium. This materials are used in HHO instalations to prevent corosion and contamination of the cells.

The ultimate angler's propulsion system. Not unlike electric bikes; adding this to SUP could be next. Way more sophisticated than my mundane ryobo 18 volt powered submersible water pump. But, no saltwater required!

that's a pretty nice presentation, clear and excelent, thank's for sharing

biggest issue I'd see regarding commercialisation is in the "leisure boat" department. some people mostly have their yachts in salt (and brackish) water, others only yacht around fresh water, some switch it up every now and then. Considering that salt water is going to be a lot easier to electrify, the setup of the 'optimal MHD thruster' might be different in salt vs fresh water, leading to wildly different outputs depending on whether the boat is in salt water or fresh water. would love to see this revisited to compare performance in salt vs fresh (vs brackish) water and to see what the differences in optimal setup would be and whether minimal adjustments (that might be made automatically, like toggling fresh vs salt water mode) would be doable.

I could watch his videos all day …

Wtg!!! Don't know why, but I knew magnetism was key a lot of scientific revolution when I was growing up...perhaps I was tapping into the Life Scrolls or someone else's tap..but I even felt it was the key to space travel(turns out it gives ship it's own gravitational field), as well as free from fuel/resource necessity which is totally awesome to be APART of the generation/ERA to bring about SO MANY IMPLEMENTED IMPROVEMENTS THAT NOT JUST HELPED MANKIND BUT TURNED AROUND OUR PLACE UPON THE PLANET WHERE WE HELPED IT RATHER THAN HURT IT AND THUS HURT EVERYTHING AND EVERYONE ELSE.

I think you’ll find the exposed electrodes in the water are causing losses. The whole point of the drive is to accelerate charged particles, in the form of ions in the salt solution, using Lorenz force. By having the electrodes exposed you’re allowing ions to loose their charge and escape as gases. You should insulate the electrodes to prevent this, while the losses may be minimal you should still do it to prevent chlorine/hydrogen from being produced which could potentially cause you harm. This may also be the reason why you’re not finding gains in fluid velocity when moving the electrodes closer, as this makes it easier for the ions to move to the electrodes and neutralise, increasing losses. Oh and Lorenz force is governed by electric field flux density, not potential, (I think) so I’d be measuring the effect of current rather than voltage on performance for more direct results. Sorry for the long reply lol, I think the project’s really cool and I’m planning on building one myself at some point!

Hi , I have been a sea captain for 45 years and found this very interesting . I don't know if anyone has mentioned that the anode on boats naturally degrades and gets eaten away . This would be a real problem as the more you increase the power the faster the anode and cathode will disappear. if you can overcome the degradation problem it may be viable . Just look at the anode zinc blocks on a standard vessel . Electrolysis will eat away a steel hull very fast if the zinc anodes are of poor quality or are badly connected . Just saying this is a problem . Good luck

Linear induction motor. Vary phasing and frequency thru several coils in physical series but electrically variable phasing to add push to the liquid.

"The world trembled at the sound of our rockets, they will tremble again at the sound of our silence!" Sean Connery as Captain Ramius in the film "The Hunt for Red October" based on the Tom Clancy novel of the same name.

Very interesting, good job I'm excited with this

Higher voltage also increases the rate of hydrolysis (lost energy), reducing efficiency. It voltage/current also increases the corrosion rate, so you would likely need to coat in inert material (platinum) for long-term use.

This is cool Read about these drives in Clive Cussler books for the past 20 years That’s a cool application

The US navy did experiment with MHDs but found that they are still plenty loud at high thrust levels because of all the bubbles formed on the electrodes, and a large slow turning prop is very quiet especially next to all the pump noise for cooling the reactor.

More space for the same velocity means moving more water, more work. You may be capping how much your magnet can push within that area, and it's dumping the excess energy into heat? maybe corrosion? Can probably have some fun with bernoulli's principle.

Closer spacing also increases the channel resistance of the water flow, cancelling out the effect of the higher current.

When looking at the spacing you only measured velocity and not mass flow. You may find that the wider spacing gives improvements as your percentage losses to wall friction will also be reduced with a larger cross section. Height or depth of the thruster would also be something to optimise again whilst looking at the mass flow.

electrolysing salt water (indoors too) is such a great idea, like i get this is small scale but idk i personally wouldn't.

Thank you for making it simple and understandable.