Has Wiffleball Been Created Ever?

[Joseph Chikva]

Joseph,

I must say that accepting evidence presented is not your strong point. But maybe some study will help. Or not.

http://home.physics.ucla.edu/calendar/c ... vandam.pdf

http://www.afs.enea.it/zonca/references ... _rnc99.pdf

http://iopscience.iop.org/0741-3335/34/ ... 53925EE.c2

http://epsppd.epfl.ch/Montreux/pdf/P1_121.pdf

Theoretical analyses predict that shear Alfvén waves may be driven unstable by energetic particles (with energies in the MeV range) in thermonuclear plasmas, e.g., by fusion products. Indeed, these waves have been experimentally observed and – in certain circumstances – found to be responsible of significant energetic particle losses. This fact, together with the possible detrimental effect of these instabilities on the plasma performance – in the perspective of a fusion reactor –, has attracted significant attention on the topic. The present review article is focused on both linear stability and non-linear dynamics of shear Alfvén in tokamaks, the presently most successful experimental machines devoted to the study of fusion reactions via magnetic confinement of thermonuclear plasmas. The present theoretical investigation highlights both analytical and numerical approaches to the problem.

http://www.afs.enea.it/vlad/Papers/revi ... RNC_2.html

Thank you for references. But nobody states that these types of waves or some other types of instabilities are not in existence in TOKAMAKs. Nevertheless you can not you can't disprove the indisputable fact that confinement time in JET TOKAMAK has an order of several seconds. Simply, instabilities in TOKAMAKs unlike to any other fusion concepts including Polywell are much better investigated.

Steady progress has been made since in fusion devices around the world. The Tore Supra Tokamak that is part of the Cadarache nuclear research centre holds the record for the longest plasma duration time of any tokamak: six minutes and 30 seconds. The Japanese JT-60 achieved the highest value of fusion triple product—density, temperature, confinement time—of any device to date. US fusion installations have reached temperatures of several hundred million degrees Celsius.

[kcdodd]

I think you might be confusing confinement time with pulse duration. The expected confinement time of ITER is something like 4s. I might be wrong but I think JET is at about 1s. The pulse duration is something different and can be much much longer.

[MSimon]

The present review article is focused on both linear stability and non-linear dynamics of shear Alfvén in tokamaks, the presently most successful experimental machines devoted to the study of fusion reactions via magnetic confinement of thermonuclear plasmas. The present theoretical investigation highlights both analytical and numerical approaches to the problem.

[Joseph Chikva]

I think you might be confusing confinement time with pulse duration. The expected confinement time of ITER is something like 4s. I might be wrong but I think JET is at about 1s. The pulse duration is something different and can be much much longer.

No confusion. Confinement time = pulse duration, from which some time the toroidal current is driven by induced electric field and then so called bootstrap current is driven. Projected confinement time for ITER from 500 to 1000 sec. While according to different soerces confinement time for JET from several seconds to 20-30 sec. See wiki http://en.wikipedia.org/wiki/Joint_European_Torus "Flat top pulse length" and "Lifetime of the plasma":

Machine information
Weight of the vacuum vessel: 100 tonnes
Weight of the toroidal field coils: 384 tonnes
Weight of the iron core: 2800 tonnes
Wall material: Entirely Beryllium save Tungsten 'exhaust'
Plasma major radius: 2.96 m
Plasma minor radius: 2.10 m (vertical), 1.25 m (horizontal)
Flat top pulse length: 20–60 s
Toroidal magnetic field (on plasma axis): 3.45 T
Plasma current: 3.2 MA (circular plasma), 4.8 MA (D-shape plasma)
Lifetime of the plasma: 20–60 s

[Joseph Chikva]

The present review article is focused on both linear stability and non-linear dynamics of shear Alfvén in tokamaks, the presently most successful experimental machines devoted to the study of fusion reactions via magnetic confinement of thermonuclear plasmas. The present theoretical investigation highlights both analytical and numerical approaches to the problem.

Really?
One simple example:
http://www.martinwellsco.com/skin/front ... eprint.pdf

A study of the literature will reveal that practically every engine builder or user has had his share of valve wear problems.

Nevertheless all we widely use internal combustion engines and other weared devices as well.

I have said and also am saying now that despite to alfven waves, ELM, other instabilities lifetime of plasma in TOKAMAKs has rather big value - enough for commercial reactors.

[Robthebob]

Sigh, lost my response when my computer crashed. I was under the impression that Joe is gone... oh well.

THANKS, RobTHEbob.

A few more concerns:

1) If wiffleball(s) has(have) been created experimentally on WB7 & WB8, then why does it take EMC2 so long to get the job done?
a) electron gun? why do they need more power? (Recovery.Gov Project Tracker)
b) money? why do not they get huge change? (Recovery.Gov Project Tracker)
c) people? as b)
d) physics? then what?
e) engineering? then what?

2) How do they get the Beta (high, close to ~1)? measured or calculated? How accurate will that be?

3) What, if it exist, prohibited the company and research go public? Americans and tons of billionaires are watching, I believe.

4) What's the "first party and third party" you mentioned? Just curious. I only see one party, that's emc2.

emc2+

the responses may seem kinda short, because I lost it all the first time, and i dont really feel like typing it all out again.

1. Science takes time. I know it's not a good answer, but it does.
1a. something about at high beta with high fields, it gets harder to push electrons into the core, that's why they got a bigger gun. It was mentioned in the J&A
1b. They dont need more, they need to finish with the science, and when they can build a demo plant, they will get more money. This whole time, emc2 has been on a leash, and I doubt Navy will change their policy. Also it has to do with Dr. Bussard being paranoid
1c. They dont want to waste time, they got all the experts excluding Dr. Nebel, we're not sure what happened there. The machine isnt big and doesnt have many parts, so they dont need more people to handle the experiment.
1d. well if the physics work, then it all pretty much works, because the engineering challenges of polywells are not as crazy as toroidal magnetic confinement machines, like making the walls of the core out of materials that doesnt exist (I'm looking at you ITER)
1e. see above.

2.

1. Science
2. Magic
3. ????
4. ????
5. profit

well beta is a number that has two parts, 1 part is pretty much measured, the other part is pretty much calculated.

http://en.wikipedia.org/wiki/Beta_(plasma_physics)

The plasma pressure depends on density and temperature, which both are pretty standard measurements that can be done by various plasma diagnostics methods. For density, as an example, there's a way called microwave interferometry, which emc2 is doing right now. Much like how light gets bent in water, the microwave gets bent by the plasma; the phase shift is related to the electron density. (btw, I realized that for this system, the fuel have to be in the system, or the wave cant travel through the machine, thats decent news) The magnetic field pressure is calculated, they put on some field, that field has some sort of pressure. It's about as accurate as any other lab plasma experiment with those same parameters.

3. The Navy is the funding source of emc2, and they put them back on publication embargo after they went back on their funding. (seriously, a lot of these information, on 3 especially is all pretty common knowledge on this forum and/or common knowledge within the field of plasma physics)

4. ?????????????????????????????? and then Profit.

Seriously tho, this is in the J&A, go read it. It states in there that the Navy got a panel of independent plasma physicists who are experts in magnetic confinement, and they looked at the data and the theory, and they said the two were consistent. emc2 is the first party.

[Robthebob]

Dan,

Any clue on the "more definitive plasma density testing method"? What's the "less" testing way?

Even if it's 100% accurate, one can not obtain the beta from density alone: am I wrong?

Hearsay and implied information are the real players in "The Emperor's New Clothes".

emc2+

It's not so much hearsay, I mean... I talked to Dr. Gilmore, I did microwave interferometry for undergraduate research, it works... It's also not really hearsay if it literally said on the emc2 progress report on the recovery act website that it's what they're doing. (well it says what they're going to do during first quarter of this year)

[mvanwink5]

Everything is hearsay unless you do it or see it yourself.

[Joseph Chikva]

well beta is a number that has two parts, 1 part is pretty much measured, the other part is pretty much calculated.

http://en.wikipedia.org/wiki/Beta_(plasma_physics)

The plasma pressure depends on density and temperature, which both are pretty standard measurements that can be done by various plasma diagnostics methods.

Someone here said that evidence that beta=1 for Polywell is in that Polywell losses more particles than that was expected as casp losses.

But MSimon has provided a good reference of Alfven waves from which everyone really interested can see that TOKAMAK that has not any casps even at beta=0.1 and even lower may suffer significant losses.

I see that now you are stating that beta for Polywell was measured/calculated. Very well.
Can you please provide the following numbers of:
-electron number delsity
-electron temperature?
We know that B field in WB-6 was 0.1 T. So, we can easily calculate mag pressure. But we have a big problem with calculating of another part.
Can you help?

[Robthebob]

Joe, what the crap, I wasnt talking to you.

Those two values are measured, like i said, by standard plasma diagnostic methods. We know these are not problems, because they're not a problem in other experiments, other machines; a microwave interferometer works the same way as in a tok, a reverse field pinch, in a polywell, in a unicorn, in a whatever. I worked with the CTH, and we get measured values for density and temperature by your good old standard plasma diagnostic methods.

I so happen to know that emc2 is using a microwave interferometer to measure the plasma density, so can we just leave it at that? Let scientists do the science? Do you want me to go ask what method they use to measure the plasma temperature? Maybe they use multiple methods to measure the plasma density, do you want me to go ask for those, too?

[Joseph Chikva]

Do you want me to go ask what method they use to measure the plasma temperature?

No, I want only two numbers. Regardless to method of measurement.

Also, since from the beginning of this thread I could not see any your post. This is an answer on yours "I am not talking with you"
And why? Difficult to answer?

[D Tibbets]

Dan,

Any clue on the "more definitive plasma density testing method"? What's the "less" testing way?

Even if it's 100% accurate, one can not obtain the beta from density alone: am I wrong?

Hearsay and implied information are the real players in "The Emperor's New Clothes".

emc2+

Bussard, etel did simple tests on multiple machines. The e_guns were on at constant voltage and current, and the electromagnet was turned on and ramped up. T he Photomultiplier tube measured brightness of the plasma. It peaked as expected in the region when Beta=1 conditions would be expected. It is difficult to contest this data of increasing brightness to a peak, then falling without invoking Beta= 1 conditions being obtained and passed. The attack on the instrumentation was possible though. The plasma brightness was assumed to be from mostly recombinations and the comparable density. This is messy and may have been uncertain. WB7 work included this Beta scaling test with a different method of measurement. It is mentioned in this forum and involved laser interferometry (?). I can't find my list of Nebel quotes. Nebel did mention that the alternative measuring method confirmed the PMT measurements

I can add that with reliable measurements indicating Beta=1 conditions., the Wiffleball formation is implied.Of course this says little about stability and costs, except that the power applied was enough to drive to Wiffleball conditions. I suspect these tests were done at lower voltages, densities and B fields, so loss scaling issues were not necessarily addressed.

Dan Tibbets

[kcdodd]

I think you might be confusing confinement time with pulse duration. The expected confinement time of ITER is something like 4s. I might be wrong but I think JET is at about 1s. The pulse duration is something different and can be much much longer.

No confusion. Confinement time = pulse duration, from which some time the toroidal current is driven by induced electric field and then so called bootstrap current is driven. Projected confinement time for ITER from 500 to 1000 sec. While according to different soerces confinement time for JET from several seconds to 20-30 sec. See wiki http://en.wikipedia.org/wiki/Joint_European_Torus "Flat top pulse length" and "Lifetime of the plasma":

Machine information
Weight of the vacuum vessel: 100 tonnes
Weight of the toroidal field coils: 384 tonnes
Weight of the iron core: 2800 tonnes
Wall material: Entirely Beryllium save Tungsten 'exhaust'
Plasma major radius: 2.96 m
Plasma minor radius: 2.10 m (vertical), 1.25 m (horizontal)
Flat top pulse length: 20–60 s
Toroidal magnetic field (on plasma axis): 3.45 T
Plasma current: 3.2 MA (circular plasma), 4.8 MA (D-shape plasma)
Lifetime of the plasma: 20–60 s

No they are not the same thing. Confinement time, as in energy or particle confinement time, is the time scale for energy and particle transport out of the machine, which is independent of how long the machine runs. For the energy confinement time, it is defined essentially as the energy content of the plasma divided by the loss power (and in steady state, the total heating power). And this quantity of course depends on the plasma parameters themselves. So I hope you can get this part straight.

[MSimon]

The present review article is focused on both linear stability and non-linear dynamics of shear Alfvén in tokamaks, the presently most successful experimental machines devoted to the study of fusion reactions via magnetic confinement of thermonuclear plasmas. The present theoretical investigation highlights both analytical and numerical approaches to the problem.

Really?
One simple example:
http://www.martinwellsco.com/skin/front ... eprint.pdf

A study of the literature will reveal that practically every engine builder or user has had his share of valve wear problems.

Nevertheless all we widely use internal combustion engines and other weared devices as well. :)

I have said and also am saying now that despite to alfven waves, ELM, other instabilities lifetime of plasma in TOKAMAKs has rather big value - enough for commercial reactors.

Ah. So you are aware of the instabilities. If they can't be brought under control with the current ITER design the confinement will not be near as long as projected. It would be on the order of 1 second not 1,000.

[emc3]

Thanks.

To my understanding, polywell concept is based on non-maxwellian plasmas:
1) good to know that density is measured
2) for temperature, how? like to know, if you can help to ask

Thanks again.

emc2+

I so happen to know that emc2 is using a microwave interferometer to measure the plasma density, so can we just leave it at that? Let scientists do the science? Do you want me to go ask what method they use to measure the plasma temperature? Maybe they use multiple methods to measure the plasma density, do you want me to go ask for those, too?