Hello from London

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Hello from London

Postby JonathanH13 » Fri Dec 31, 2010 1:57 pm

My name is Jonathan Howard, I live in London, UK.

I love physics! And like most of us on here, it's pretty much an all consuming passion. I have a degree in Electronic Engineering, a masters in Neuroscience and a PhD in Synthetic Intelligence.

I work for a large pharma company as a biomedical physicist, looking after two MRI scanners, two PET scanners and two cyclotrons. At work I have access to a lathe, mill, etc. We also have a 3D printer which is handy - I built a little forge in the garden and do some metal casting off the 3D printed parts.

I am old enough to have 'caught the wave' in home PC's back in 1980, and have been writing software ever since. I’m also pretty good with graphics/computer generated art. For my PhD I built a large cognitive architecture (complete with autonomous mobile robot), which worked very well. But our technology is 'just not there yet' for massive parallel architectures - so I'm going to leave that field alone for 10 years and do some fusion in the meanwhile ;)

I'm very concerned about the environment, and have been working with alternate/renewable energy systems for around 20 years. Some of the highlights of this work involved launching homemade rockets into African thunderstorms with ground wires attached. Oh, and a 10 meter diameter parabolic solar concentrator. It's briefly described on my website:

http://jonathanhoward.org/

I travelled around the world for five years, making a point of crossing the length and breadth of every continent, overland. This has given me a fairly good idea of the culture, aspirations and dreams of the world's population, along with their general foolishness, greed and ignorance.

Oh, and most importantly! I'm a rock-climber, and the climber's philosophy saturates every fiber of my being - that is, use your brain, not your muscle - although if you're not bleeding you are not trying hard enough. I guess it also involves risk, and doing difficult things just because they can be done. Persevere!

A recent documentary about my fusor:



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Re: Hello from London

Postby William A Washburn » Fri Dec 31, 2010 5:13 pm

Welcome Jonathan,

I'm very impressed with your computer work and especially your lab.
In addition, it looks like you are one of the folks who actually gets
things done. Best of luck with your continuing renewable energy
research. I think its about time we actually began.

I'm retired from 40 years of computer systems analysis. I'm just
an old rascal with an old BS in applied mathematics. I did spend
half of my study in the physics department before switching to math
which is why i am trying to re-educate myself in current physics and to
build a lab. Physics was my real first love.

Happy New Year, Bill Washburn
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Re: Hello from London

Postby chrismb » Fri Dec 31, 2010 6:59 pm

Thanks for the info/intro, Jonathan. That's a lot of cool stuff you do/done. Not all in London, by the sounds of your S.African accent?

I've been slow to post an 'intro' for myself yet. I'm just a plumping-up middle aged engineer and feel quite un-cool these days (with no lovely wild land like John F or Doug, no yachts, no sporty activites!.. sigh... such is family life!).

Anyhows, a happy new year to you all on this forum, and here's looking at a productive 2011 for all! I've only got my 'lab-space' for another year, so what I don't achieve [and show y'all] in 2011 I'll likely never get to do.
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Re: Hello from London

Postby chrismb » Mon Jan 03, 2011 4:56 am

Jonathan, are you in a position to say what experiments you want to do with your fusor? You indicated that you had some things you want to try, with a view to heading towards over-unity output.
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Re: Hello from London

Postby JonathanH13 » Thu Jan 06, 2011 2:27 am

Bill, Chris,

Thanks! I'm very glad to be onboard with such a talented group. Yes, originally South African, but I've been in the UK now for over 10 years, which I like to grumble about.

>Over-unity output.
Hmmm, well my thoughts on this are pretty much based on the results from Doug's fusor - that is: moving the entire system towards lower pressure and higher voltage with a strong external ion source. That is easier said than done though, what with feed-through problems and contamination issues. But the physics makes sense and this is the direction that I'm going in - first 60KV, and then 80KV.

Another point concerns reducing the input power - if one can achieve the same fusion rate with higher efficiency power-supplies and pumps, then less output power is required to achieve unity. Although this is kinda 'stating the obvious' and is only going to get us so far, consider an analogy such as: Early pioneers of flight building an airplane from lead - accurately engineered in every detail. It would be aerodynamic and structurally accurate, and it could even taxi on the runway, but it would never be capable of flight, simply because it is too heavy.

While we are on analogies, something else I like to consider is this: imagine a car with a badly tuned engine - able to drive, but only slowly, with tremendous inefficiency. But just tune it correctly and suddenly everything works, even though the design and infrastructure of the vehicle has not changed at all. This point refers more to the chaotic nature of the fusor - once inside the chamber the ions are not controlled, regulated or synchronized in any way. They are not even very well focused. That's not really a good design for an engine! Improvements in grid precision, field homogeneity, and pulsed input power result in considerably more fusion collisions - this really makes sense to me.

At some point I would like to try introducing heavier fuel mixtures such as deuterium with tritium or boron. I have a little bottle of pure boron metal standing by. 8-) But I know what the implications of this are, and realistically, any system utilizing these fuels (or approaching unity on deuterium) is not something you want to be in the vicinity of. So I'm some way off trying this. It is one thing to generate measurable fusion, but it's a whole other ball game to go for over-unity.

I also have some ideas on magnetically shielding the grid, a bit like a polywell, but utilizing a different geometry. This may require a super-conductive grid shield, complete with cryo-pump and helium compressor, which I have, but am reluctant to install due to liquid helium logistics. I went some way into writing a software simulation for it, but gave up after realizing that any accurate simulation would require several years of team effort. The first baby step in exploring this idea is establishing a fully functional and reliable system as a benchmark, and I'm not there yet with my neutron measuring capabilities, and several other loose strings. But I do aim to test, verify and/or discard several ideas this year, so it looks like 2011 is going to be a great fusor year for many of us!
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Re: Hello from London

Postby Bill Fain » Thu Jan 06, 2011 9:59 am

Jonathan, Hello. I gather that tritium may be a little easier to obtain in the UK than the States? Reason I say this is we're pretty much unable to obtain any other than gun sights or watch dials. Exit signs are regulated. Even the tritium key ring I have I had to order from Ebay/UK. You can obtain it over here if you're a university or a business with government ties and only then after extensive paperwork. procedures, safeguards etc. -bill
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Re: Hello from London

Postby Doug Coulter » Thu Jan 06, 2011 10:30 am

This all brings up the idea of a complex "error surface" loud and clear. Optimizing along a gradient from wherever you happen to be gets you to a local minima in that surface for sure -- it just many not be the global one -- to find a global in a complex surface requires another strategy, like simulated annealing or a genetic algorithm (and you, Chris, are our wildcard there). One thing I seem to be finding out is that it's effective density at the interaction zone that seems to matter most, and that at least in a local sense, going to lower gas pressure, higher voltage helps with that (along with other things), even though the basic media is less dense -- this is taken from years of work with electrons, same issues in various electron-based devices -- same issues, just a different scaling factor involved there (and with ions, it tends to be worse re defocusing). It only needs to have high luminosity in the collision zone, having it elsewhere just makes it want to "Coloumb explode", attract neutralizing electrons, and be hard to manage. Hence the various approaches by others that seem to think that having a bunch of electrons in the mix will cancel some of that out. I personally am having troubles making that work philosophically, due to some experience with what the electrons actually do -- where they wind up in the mix at least in the rigs I've tried so far.

In fact, in my estimation, the electrons are the very main source of losses in a normal fusor, from visible light, to X rays to heat to neutralizing ions you've invested significant energy in and taking them out of the game. Not too surprisingly, a Faraday probe "out in the tank" always reads very negative (in non pulsed running) -- there are far more electrons in play than ions in my particular lashup, which has encouraged me to try grid materials with less secondary emission, and propose a new design of shielded grid (more on that in its own thread, soon). Having run the numbers and thought about it some, I think Jon and I might be on the exact same page re a bit of magnetic shielding. For example, in a cylinder fusor, one might consider a couple of donut magnets with the H field aligned down the length of the cylinder. "In theory" this should inhibit the electrons released from the grid due to ion impacts from having a straight path to the tank walls. It's worth trying, I've got the stuff, but just haven't gotten to it. A minute worth of math says that it should not take a lot of field to have quite an effect on electrons while barely perturbing any fast ions -- you might even get some good out of increasing their path lengths, due to the fact that they will help ionize more neutrals, like in a magnetron ion gage. Of course, I know from experience that any permanent magnet will quickly be fried in there, but speaker type ceramic donut magnets are cheap enough to be worth roasting a couple in the attempt -- if it works, then one could solve the other problems involved. Probably best to try a duct tape class solution first to see if it's worth going down that road, in an otherwise well characterized situation. When I have that (not quite, yet), then will be the time to give it a go. At this instant, cracking the door to put them in changes so many other things that it wouldn't be a conclusive test, and making that level of field from outside the tank is onerous to do for the "just try it" attitude. Probably need about a k gauss for that.

As Jon says -- reducing input power is the way to go for a home situation. If you got to breakeven, or even factor 100 better than now, at these input powers you'd be life threatening danger at hundreds of watts input. Our little finding of higher Q's in a pulsed mode still made millions of fusions/second -- but at 5 watts input. That's about the limit of what I want to have in my house!

TD fusion is known to be about 100x better than DD in most setups, but T is a little hard to get hold of, and is a controlled substance in most countries, so sadly, we can't talk about it all that much here without risking some issues we don't want to have with our governments. It's available in tiny quantities (glow in the dark things like gun sights and exit signs), however, so at some point I suppose we try it. Those super high energy neutrons from that reaction are going to be an issue, as ITER is just figuring out, re damage to everything else. A possible issue in a fusor is the differeing charge/mass ratio, which would affect focus if one believes the classic math on that one. All other known fusion reactions take more input energy, and are harder to measure the output from till you get a lot closer to breakeven. I'd love to be working with say, P->Li for example, but how to see the hot alphas in a sea of hot protons? Further, if working with Li metal, it would get all over everything in the tank, especially insulators, and wreck them. LiF is a possible candidate, but would release some F in the process, also not very good for the gear.

I second the idea of skipping the cryo. Where I live it's just not realistic to tool up for. The nearest place one can have it delivered is an hour drive from here and that is huge added expense. I'd have to see a really good justification to want to go there, and the only one I have now is that it'd be nice to have a really good gamma spectrometer (Ge), which needs that. For now, I'd settle for a mediocre one instead.

As many in the big-science fusion field point out, you don't even really need breakeven to be useful -- you can use the neutrons to breed things and drive non-chain reactions that have gain when driven as well, I don't like this much, but it's there.

But Jon and I agree in (more than) one thing -- going big before we go at all seems not that smart. If we could, in the limit, fire just two ions at one another and get enough precision and so on to get a very good interaction probability -- we'll have done something no one else has yet (including the big science boys), and at that scale (or much nearer that scale than we now are) and without the complications of a bunch of electrons, we have a better chance than just pouring the coals to it and hoping it all works out. After all, that's been done since Farnsworth, and while we are close to duplicating his most optimistic results, even exceeding them in some cases, it's not by much at all -- that road is well trodden, and I'm not so vain as to think that for sure I'll find a secret there that no one else has noticed. It's happened to me in other endeavors, but it's an outlier, statistically. I much more favor ideas that have worked out well in cases where few ions have been precisely controlled and marshaled to go where you want, when you want, simply refined from what's been done and with raised energies, as I've proposed on another thread here. A dense group of charged particles is about the most difficult thing there is to control, so why not skip the density except for just where you need it -- at the interaction zone, and just when you need it -- the time they are all there, and let things spread out the rest of the time?

Seems logical to me, at any rate, not to try the extremely difficult before trying the obviously quite possible. The limit there seems to be -- you need a short focal length to get the time they "see" one another and repel short in both space and time, but to have low enough density to control outside the focal area, you need room to let them expand when they are not actively headed to the interaction point.

It's just taking awhile to build and get characterized -- if my back of envelope math is close, that's going to need one heck of a good video amplifier, the likes of which really don't exist off the shelf. Luckily, it looks do-able with very similar kit I already mostly have. I have some other plans to engage before that one -- I want to try my shielded grid idea, and get some more probes in there to measure what exactly is going on with what we have already for reference first, as a logical next step before I take the big leap to the new design, as I think what I'll learn (and share) from that will be valuable regardless, and it's a relatively easy thing to do right now. As we used to say in the troubleshooting business -- always check the easy stuff first.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Hello from London

Postby chrismb » Fri Jan 07, 2011 7:33 pm

Doug Coulter wrote:In fact, in my estimation, the electrons are the very main source of losses in a normal fusor
...and it is also my assumption. Electron loss. Stop it, if you can, and get an instant >oom or two improvement.

Doug Coulter wrote:there are far more electrons in play than ions in my particular lashup
hmmm... the electron flux is surely higher, but I think Gauss might disagree that there are more electrons than ions, at any given moment....

Doug Coulter wrote:Having run the numbers and thought about it some, I think Jon and I might be on the exact same page re a bit of magnetic shielding.
Absolutely. You only need a few 10's of Gauss to stop electrons. I put a link to this calculation in the other thread.

As you do this, though, you will end up getting closer and closer to my set-up! If you decide to also have pulsed-driven electric fields, to pump the ions into a given region of velocity space and to maintain them there, then at that point you are running with the fundamental basis of what I am trying to do.... that pretty much summarises what I am trying out (the rest is just 'detail')!
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Re: Hello from London

Postby Doug Coulter » Fri Jan 07, 2011 7:47 pm

Chris, in an ion trap you can have "just ions" and in an electron tube you can have "just electrons" right? Does your middle point mean those can't happen (outside the universe as a whole presumably being neutral)? Charge separation exists, and with a power supply that "pumps" electrons, I can surely have more of them than I have ions in a space, which is in fact the case of any old triode tube with a bit of gas in it (not counting the solid parts of the tube of course). And that's both amount, and flux.

We might be converging on what you're doing, but maybe not at all. I think the key novel thing in your approach is maybe not what you think, but I'm willing to be educated. There's a ton of prior art on using E and/or H fields to manipulate charged particles, surely you're not claiming to have invented all of that.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Hello from London

Postby chrismb » Fri Jan 07, 2011 8:14 pm

Doug Coulter wrote:Chris, in an ion trap you can have "just ions" and in an electron tube you can have "just electrons" right?
Yup. But in an ion trap, the electrons are all ejected in quick order due to the e/h field config that will confine either + or -, not both. If you are saying yours is like an ion trap, then does it trap + or -? If you are saying there are more electrons, then it traps -ve charge. Is that what you think your set-up does?

In a valve, the electrons leave the surfaces of conductors and it is sufficiently evacuated that they form no ions.

Also, in an ion trap, the charge you can trap is truly poor. This is the problem with the first version of my device - it is basically a glorified Penning trap - and the simulations give a dire max power output [even if it can do it efficiently, it will still not be hugely impressive for fusion - a kind of 'advanced fusor' rather than a means to high rate, efficient fusion reactions].

But, don't get me wrong, if you take a fusor into an ultra-low regime then I can see that you might end up with more electrons. I'd be looking for more data than just a Faraday cup, though, because a higher electron flux would give that reading - wouldn't it?



Doug Coulter wrote: I think the key novel thing in your approach is maybe not what you think, but I'm willing to be educated. There's a ton of prior art on using E and/or H fields to manipulate charged particles, surely you're not claiming to have invented all of that.
For sure I don't claim that. I make it very clear that my device is a crossed-field device just like a cyclotron is, but with radial electrodes (rather than two dees) or like a Penning trap with the end cap electrodes pulled in. All the same config. What I would claim, though, is that I am a pioneer of pumping ions into a given region of velocity space [and using a crossed-field device to do it].

I'm not the only one to have discussed the principle of ion energy pumping (I can't say if I was the first to think of it - my idea is 28 years old now and I don't know if anyone had the same idea by then) but I do think I am the first to come up with a truly viable way to achieve it. Todd Rider discusses pumping ions into resonance in his thesis (which I saw after I devised my scheme) and it has also been a point of discussion in a few of Nebel's 'POPS' scheme descriptions. E-cross-H fields are well-known, but I do claim I'm the first to rotate them to pump ions towards a given locus in velocity-space.

I do also think I am the first to show mathematically that such a mechanism can yield net fusion energy gains:
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