Hello All,
The newest post is up.
The blog passed 10,000 pageviews on June 30th!
This new post is a very long review Joe Khachan's work.
http://thepolywellblog.blogspot.com/201 ... sults.html
Post Summary:
==========
This models the 2010 Sydney experimental paper and contains ideas similar to those in their 2011 modeling paper. But, this predates that paper by five months and is not peer reviewed. A ~6 cm Teflon device with 10 turns of copper wire was put ~30 cm away from an electron emitter in a bell jar at 0.015 torr. A probe, measuring electrons was in the ring center and 2,500 amps of direct current (at 450 volts) went into the rings. At full strength, the rings push apart with a ~0.2 Newton force. Tests explored how the trapping changed with chamber pressure, ring current and electron injection voltage. The use of Teflon, aluminum and 304 steel is critiqued. The ring design of ~21 mm spaced apart rings is critiqued for having excess metal (it is now known that rings are spaced so that the joint and axis fields equal.)
The physics of the electron for one test (ring current: 625 amps, pressure 15 mTorr, beam voltage: 15 KeV) is modeled. The electron is made using thermionic emission, feels an electrostatic Lorentz force pushing it the ~10 cm to the rings. The gas has a mean free path of ~6 meters. The average electron arrives at the rings in ~7.2 nanoseconds, going ~2.5E7 m/s and experiences a ~0.013 tesla field (per ring). First, the electron beam is treated as uniform. If it has 1 degree between the magnetic and velocity vectors, the magnetic is higher than the electric Lorentz force and the electrons are caught. Next, electron velocities are modeled like a spreading bell curve using a Wiener process, where an interaction takes 320 attoseconds and exchanges 3.2E-21 joules of energy. This predicts ~23 million interactions inside the beam before reaching the rings. The beam has a ~1 cm diameter with density of 1E8 electrons/cm^3 and is modeled over a 0.5 cm chunk. With a 3 degree difference, this predicts the slowest (~1.4E7 m/s) and fastest (~3.2E7 m/s) moving electrons will both be caught. Modeling is not done after fill up. The number of electron transits (~42,000) is found using a lifetime of 100 msec and a transit distance of ~6 cm. 155 volts measured in ring center means ~10 billion electrons were trapped.
The paper indicated that electron trapping generally peaked at an ideal ring current – this supports a tunable machine. This observation is connected to magnetic mirror theory. The ratio of particle velocity and characteristic field length is compared to the electron gyroradius. When the ratio is higher than the radius, the mirror fails. As the ring current dissipates, the ratio falls. When the ratio is less than the radius, the mirror works and electron containment spikes, this supports a “peak” ring current. An experts assessment is called for. Next the mirror ratio (the ratio of the max and min magnetic fields) and loss cone concepts are discussed. FF Chen’s textbook explanation and a difference between it and the papers definition are included. Results suggest that lowering the pressure and raising electron injection voltage improves trapping. A price of $12,000 for equipment is estimated.
The New Post is up
The New Post is up
Last edited by mattman on Wed Nov 21, 2012 9:15 pm, edited 2 times in total.
There are some interesting discussions, though it is hard reading. There are some poorly used terms and some typographical errors, but still interesting.
A brief abstract of the paper
http://m.pop.aip.org/resource/1/phpaen/ ... horized=no
implies that yes, significant virtual potential wells/ cathodes can be formed with a Polywell configuration and that it is highly dependent on the electron current/ B- field relationship. I'll take this to mean that their "resonance" was actually a high Beta condition. This is implied by Bussard's discussion of the electron pressure (density * energy) compressing the magnetic fields to reach a Beta= 1 state with resultant minimal losses. The pressure (10s of Microns (a little more than ~ 10^-5 atmospheres would seem to be a poor choice when considering Bussards target of pressures ~ 100 times less because of arching- glow discharge concerns and how that demolishes the ability to achieve high potential well. I suppose that several hundred volt potential wells for several milliseconds under these very compromised pressure conditions and weaker magnetic fields may be encouraging for trapping effects and possible Wiffleball conditions that are thus implied.
Dan Tibbets
A brief abstract of the paper
http://m.pop.aip.org/resource/1/phpaen/ ... horized=no
implies that yes, significant virtual potential wells/ cathodes can be formed with a Polywell configuration and that it is highly dependent on the electron current/ B- field relationship. I'll take this to mean that their "resonance" was actually a high Beta condition. This is implied by Bussard's discussion of the electron pressure (density * energy) compressing the magnetic fields to reach a Beta= 1 state with resultant minimal losses. The pressure (10s of Microns (a little more than ~ 10^-5 atmospheres would seem to be a poor choice when considering Bussards target of pressures ~ 100 times less because of arching- glow discharge concerns and how that demolishes the ability to achieve high potential well. I suppose that several hundred volt potential wells for several milliseconds under these very compromised pressure conditions and weaker magnetic fields may be encouraging for trapping effects and possible Wiffleball conditions that are thus implied.
Dan Tibbets
To error is human... and I'm very human.
thanks mattman - good post.
some of it looks familiar but i will give it a good read through.
Khachan's paper was published May 2010. i wonder what he has been up to from then till now?
i have made an implicit assumption, that Nebel is probably several years further forward in understanding. but it is essential that someone run's a follow-up to establish all the missing facts for all the rest of us mere mortals living outside of military contracts, most particularly if anything ever comes of it.
some of it looks familiar but i will give it a good read through.
Khachan's paper was published May 2010. i wonder what he has been up to from then till now?
i have made an implicit assumption, that Nebel is probably several years further forward in understanding. but it is essential that someone run's a follow-up to establish all the missing facts for all the rest of us mere mortals living outside of military contracts, most particularly if anything ever comes of it.
aha, something like it perhaps...
well, he has his eye on it at least. i'm encouraged.http://thepolywellblog.blogspot.com/2011/07/modeling-some-real-results.html wrote:...
In this case, the pattern {of experimental data} is: a sharp step around 100 amps. This is their threshold value, or as we have been calling it the “resonance current”. This indicates that an interesting physical process is happening at that current. They believe this process is the magnetic mirror phenomenon, as described above. The 625 amp data does not necessarily follow this pattern – so they were careful about what statements they could make....
very well written article btw mattman. did you write it?
the missing pressure and voltage figures from their graph seems a bit slack however. did they publish it like that. or did Khachan simply forget to go to work one day.
the 'magic' b-field number doesn't really surprise me but his analysis is interesting. its good that he is looking at it.
shame it is still more theory than actual data. but it all helps.
the missing pressure and voltage figures from their graph seems a bit slack however. did they publish it like that. or did Khachan simply forget to go to work one day.
the 'magic' b-field number doesn't really surprise me but his analysis is interesting. its good that he is looking at it.
shame it is still more theory than actual data. but it all helps.
A couple of thoughts I have after working on this post for 2 months:
1. The Mirror ratio is a big deal. I think I smell a problem with Rider's 1995 paper. If someone has a couple of weeks to blow, I would love answers to the following questions:
1A. What Mirror Ratio did Rider Use? Was it R = 0? It might very well have been, because Rider assumed the 14 cusps the polywell have act as giant holes. IDK about his thesis.
1B. If the whiffle ball is hypothetically happening – what is the highest mirror ratio would we expect?
1C. Read Peter J Catto’s 1984 paper. It connects mirror ratio to a particle loss equation. I think the paper had 3 or 4 cases (R=0, A<R<B, B<R<C, ect…).
1D. Work it up hypothetically. Like: If we have R = X, then our Ion loss equation is this, our electron loss equation is that. I would love to make a pretty looking chart, with R values on the left, equations on the right and all the variables spelled out in simple words. Something easy to follow.
1E. Now, add in the Lawson criterion. This really makes physicists listen to you. With these loss equations spelled out, there might be a way to apply this formula to the different cases - though I am not completely sure on this.
1F. Now you have connected the whiffle ball to the Lawson Criterion. That's a big deal - because you codified the Polywell in the language the existing Fusion community loves.
2. Government research reactors. If someone gave you ___ million dollars, what kind Polywell could you build? I want to spell out a research battle plan - with a specific price tag. Just off the top of my head:
2A. The rings. How big should they be? Let us say 6 feet in diameter. What material? A super conductor? Tungsten-carbide? How much would it cost? The insulating spacers, how big? What material? What cost?
2B. The chamber. How big? Let us say it was 25 feet in diameter, and 25 feet high. How many pumps would you need to pump it down to 1E-6 or 1E-7 torr? What cost, and where would you buy these pumps?
2C. Ion & Electron injection. Rider has a good argument that injection will be a problem. Ok. So, we will need heavy duty injectors. Where could you buy such machines? How much would they cost?
2D. Diagnostics. We need Thompson light scattering. That would be huge. It would allow us to take a picture of the plasma as it moves around the reactor. That would give, temperatures, velocities, where the plasma mirrors are, ect… Now, the tool would be limited – and we wouldn’t get everything we wanted. But a movie of how the plasma moves would be big. How much would it cost? Also, some pin hole cameras would be nice, and an x-ray detector. Also a voltage meter for measuring the potential drop would be helpful.
2E. Energy recovery. About a year ago, I read a paper covering direct conversion. They studied the idea using metal panels that looked like vertical blinds. I would try and incorporate that system into this one.
2F. Power supply. We need to be able to run current through this system for more than a few seconds. How much current? How many capacitors? How much would it cost?
2G. Staffing. How many people, what specializations, what salaries?
2H. What Experiments do you run? First, we would need to establish if the Whiffle ball is happening. What are the theoretical underpinnings of that? Next, you would add in the ions. How many neutrons are you producing? What is your fusion rate?
2I. Designs would probably need to be tweaked more then you realize. Things like ring size, diameter, spacing, number of rings, and configuration.
3. Commercial polywell reactors. If, alternatively, you wanted to turn this into a commercial product - the path would be different. The question then becomes, what is the smallest, cheapest, easiest reactor I can build? Forget studying theory, designs, physics… find what works and just stick with it. Find the fastest, cheapest way we can turn this idea into a basic product. Then churn out those devices and sell them. Of course Model A, will suck. The first transistor Intel put out – was terrible. The point is you have now turn fusion reactors into a repeatable product. Cooperate America really knows how to innovate – once you’ve got the technology into that paradigm. Once money is coming in, and the product is moving out – from there, it is easy.
1. The Mirror ratio is a big deal. I think I smell a problem with Rider's 1995 paper. If someone has a couple of weeks to blow, I would love answers to the following questions:
1A. What Mirror Ratio did Rider Use? Was it R = 0? It might very well have been, because Rider assumed the 14 cusps the polywell have act as giant holes. IDK about his thesis.
1B. If the whiffle ball is hypothetically happening – what is the highest mirror ratio would we expect?
1C. Read Peter J Catto’s 1984 paper. It connects mirror ratio to a particle loss equation. I think the paper had 3 or 4 cases (R=0, A<R<B, B<R<C, ect…).
1D. Work it up hypothetically. Like: If we have R = X, then our Ion loss equation is this, our electron loss equation is that. I would love to make a pretty looking chart, with R values on the left, equations on the right and all the variables spelled out in simple words. Something easy to follow.
1E. Now, add in the Lawson criterion. This really makes physicists listen to you. With these loss equations spelled out, there might be a way to apply this formula to the different cases - though I am not completely sure on this.
1F. Now you have connected the whiffle ball to the Lawson Criterion. That's a big deal - because you codified the Polywell in the language the existing Fusion community loves.
2. Government research reactors. If someone gave you ___ million dollars, what kind Polywell could you build? I want to spell out a research battle plan - with a specific price tag. Just off the top of my head:
2A. The rings. How big should they be? Let us say 6 feet in diameter. What material? A super conductor? Tungsten-carbide? How much would it cost? The insulating spacers, how big? What material? What cost?
2B. The chamber. How big? Let us say it was 25 feet in diameter, and 25 feet high. How many pumps would you need to pump it down to 1E-6 or 1E-7 torr? What cost, and where would you buy these pumps?
2C. Ion & Electron injection. Rider has a good argument that injection will be a problem. Ok. So, we will need heavy duty injectors. Where could you buy such machines? How much would they cost?
2D. Diagnostics. We need Thompson light scattering. That would be huge. It would allow us to take a picture of the plasma as it moves around the reactor. That would give, temperatures, velocities, where the plasma mirrors are, ect… Now, the tool would be limited – and we wouldn’t get everything we wanted. But a movie of how the plasma moves would be big. How much would it cost? Also, some pin hole cameras would be nice, and an x-ray detector. Also a voltage meter for measuring the potential drop would be helpful.
2E. Energy recovery. About a year ago, I read a paper covering direct conversion. They studied the idea using metal panels that looked like vertical blinds. I would try and incorporate that system into this one.
2F. Power supply. We need to be able to run current through this system for more than a few seconds. How much current? How many capacitors? How much would it cost?
2G. Staffing. How many people, what specializations, what salaries?
2H. What Experiments do you run? First, we would need to establish if the Whiffle ball is happening. What are the theoretical underpinnings of that? Next, you would add in the ions. How many neutrons are you producing? What is your fusion rate?
2I. Designs would probably need to be tweaked more then you realize. Things like ring size, diameter, spacing, number of rings, and configuration.
3. Commercial polywell reactors. If, alternatively, you wanted to turn this into a commercial product - the path would be different. The question then becomes, what is the smallest, cheapest, easiest reactor I can build? Forget studying theory, designs, physics… find what works and just stick with it. Find the fastest, cheapest way we can turn this idea into a basic product. Then churn out those devices and sell them. Of course Model A, will suck. The first transistor Intel put out – was terrible. The point is you have now turn fusion reactors into a repeatable product. Cooperate America really knows how to innovate – once you’ve got the technology into that paradigm. Once money is coming in, and the product is moving out – from there, it is easy.
Links:
https://www.fusionconsultant.net/
https://www.thepolywellblog.com/
https://www.thefusionpodcast.com/
Twitter:
@DrMoynihan
My Profile On Quora:
https://www.quora.com/profile/Matthew-J-Moynihan
https://www.fusionconsultant.net/
https://www.thepolywellblog.com/
https://www.thefusionpodcast.com/
Twitter:
@DrMoynihan
My Profile On Quora:
https://www.quora.com/profile/Matthew-J-Moynihan
With the wiffleball effect in force, the mirror ratio is high enough that the effective hole radius is proportionate to the particle gyro-radius in the magnetic field. At lesser mirror ratios, as in a conventional mirror machine, the hole size isn't an area measure, but an angle.1B. If the whiffle ball is hypothetically happening – what is the highest mirror ratio would we expect?
Compared to a wiffleball cusp, a conventional mirror machine ratio of 6:1 or so is a giant hole. Or perhaps funnel is a better picture.1A. What Mirror Ratio did Rider Use? Was it R = 0? It might very well have been, because Rider assumed the 14 cusps the polywell have act as giant holes. IDK about his thesis.