DIII-D tokamak simulation

[moz1966]

ne tokma ardas yaa

[Yoetah]

"High-Performance Plasmas May Make Reliable, Efficient Fusion Power A Reality"

"Mr. Keshe, Is this a different system than your plasma concept?"

"It's an experimental report. Fusion thru systems like Tokamak -long term running aren't possible as they have inherent problems in translating natural process to manmade systems w/half cocked principles.

How will they bring temps of millions of degrees to a few hundred needed 4 running a simple turbine? Tokamak for E production is a gravy tray 4 some"

[anthonythechief2005]

is this at a college in san diego? and if so what is the name?

[radescg89]

Lol...tokamak is developed in Russia in 1950's

[ChrisPCrunchy]

Cause cooling? A sphere radiates energy from the area of greatest density (Its core) outward to its outer surface. In this way its core is insulated by the less dense surrounding material. Cooling is a function of surface area exposed to cooler matter and as such a sphere present a hugh reduction of exposed surface area as compared to a toroidal configeration and is simpler and easier to enclose in a vacuum as spherical containers naturally resist implosion. THAT IS MY EXACT POINT.

[ChrisPCrunchy]

Viable means of producing power with fusion are being ignored and nearly ALL research funds are being plowed into a system that cannot ever work. Tokamak reactors, despite having decades of research and billions of dollars spent have never delivered 1 watt of power and never will. All known fusion reactors (stars) are spherical, none are doughnut shaped (Toroidal). Polywell fusion works in a similar way to a star and despite showing great promise it recieves no funding and never will.

[gun844]

Hello chris look the system is working....It can produce energy.A lot of.

The polywell is just an unproven theory.

[ChrisPCrunchy]

I have read no published reports of Tokamak having broke even on energy production and certainly no reports of it actually producing energy. If you know something more please share. If not why make these random comments.

Polywell would be cheap and easy to confirm or reject. Prof Bussard had a working proof of concept unit when he was shut down.

[soylentgreenb]

"I have read no published reports of Tokamak having broke even on energy production..."

JT-60 has achieved the conditions for Q>1 but does not have the facilities to operate on a D-T plasma; tritium is expensive and a little bit radioactive.

"...and certainly no reports of it actually producing energy."

10 MW fusion power at the now very old JET facility; this is as heat of course, since there's no point in actually trying to convert it into electrical power until you reach Q = 5-10 or so.

[ChrisPCrunchy]

Energy in the form of heat is NOT useable energy. It has to be enough to overcome the losses associated with power generation and transmission to ever be of any use.

[soylentgreenb]

"Tokamak reactors, despite having decades of research and billions of dollars spent have never delivered 1 watt of power and never will."

The current record is about 10 MW fusion power.

"All known fusion reactors (stars) are spherical..."

Thermonuclear weapons are not spherical.

Our sun has an energy density of 2 milliwatts/kg; that's not even competitive with hamster-wheels as an energy source.

[soylentgreenb]

"Polywell fusion works in a similar way to a star and despite showing great promise it recieves no funding and never will."

But it is receiving funding. And this is despite not even achieving the same level of performance as the earliest, crappiest tokamaks.

It's nothing at all like a star; it doesn't operate in thermodynamic equilibrium and it doesn't use gravitational confinement and it's not particularly spherical either.

[ChrisPCrunchy]

Compare budget for Polywell to what has been wasted on the flawed tokamaks and you will see it is a fraction of their lunch money budget. As there has been no continuity of funding for polywell and a state of continual review most of that money was spent on accounting and reporting to the DOD. This type of funding is what is given to supress a technology. A project kept so short term can never attract the best people or construct usefull prototypes so it is doomed to failure from the start.

[ChrisPCrunchy]

I sugest you inform yourself with advances in IEC fusion including those at Los Alamos Physics Division.  Periodically Oscillating Plasma Sphere, or POPS is exactly whay I am talking about.

[detibry]

spheromaks have the same issues ass tokamaks. the problem is rests with the inefficiencies in confinement and energy abstraction. any fusion reaction requires a LARGE confinement potential; the sun owes its natural fusion capabilities to gravity... its geometry is a mere result of its immense gravitational potential. we, unfortunately, are only left with magnetic magnetic confinement.bottom line its a confinement issue, not geometric. if you want the power ya gotta be able to handle the power.

[ChrisPCrunchy]

You ignore Electrostatic confinement. electrostatic confinement does not require thermodynamic equilibrium as power can be drawn off directly by a grid reducing inefficiencies of steam driven turbines etc.

[drandersw]

The tokamak is the most promising concept and in the new experiment called ITER we will achieve a high gain and figure out how to deal with the world's first controlled thermonuclear fire. We will probably need at least one more experiment, a component test facility, before building a first demo reactor after ITER.

[ChrisPCrunchy]

@drandersw Let me guess another 40 years another few billion. The story never changes. A high paying job for life and one for the grandchildren too.

[ntmsup]

I find your comment a bit offensive or at least misinformed. We are making steady progress. Initially when fusion reactors were first conceived then all the challenges both regarding the physics of a magnetized plasma and the technology required to make use of the energy were not simultaneously conceived. There is nothing unusual about that. What matters is that we can succeed and this energy source holds a great promise. How long do you think you will live? Shall we compare notes in 40 years?

[ChrisPCrunchy]

@ntmsup If Polywell was funded with even one tenth the budget of tokamak we could know once and for all in under 10 years. Have you heard the lecture Prof Bussard presented to google before his death? The biggest problem with Polywell is it can scale down as well as up making small portable units that can fit in the engine room of a ship possible. The energy monopolies do NOT like this as they would lose control as communities & towns could generate their own power economically.

[ChrisPCrunchy]

@ntmsup None of us will live long enough to see a Tokamak producing usable power.

[drandersw]

You remind me of the moon hoaxers but for fusion research instead. You are welcome to have any crazy conspiracy theory you wish. I have been a scientist in fusion all my life and there have been many interesting ideas proposed but the tokamak is the most promising concept and with ITER we are taking one more important step toward a fusion reactor.

[ChrisPCrunchy]

Tokamaks have been around since their inception in the USSR back in the 50s. They have never produced one useable Watt of power. When the hell do we pull the plug on this white elephant technology.

To quote Prof Bussard who worked on Tokamak research "We have been working on the technology since the 1950s and what have we learnt?" "We have learnt that they are no darn good." This has become a meal ticket industry where a solution will never be in the interest of those working on the problems.

[drandersw]

There are many talented people working hard on relevant topics in this field. This is by no means a meal ticket industry and we are making steady progress with the resources at hand. We need ITER and at least one more experiment before the demo reactor.

I don't know too much about Bussard but it is easy to propose something and a very different story for it to work. If someone could build a small reactor to put in a ship then someone would.

[ChrisPCrunchy]

@drandersw Someone could if Tokamak wasnt taking ALL the civil / government funding. Who knows maybe they already have as most of the reseach dollars have come or are coming from the Dept of Defence not Dept of Energy. Prof Nebel is working with a paper thin budget. Any technology will no doubt have a stratigic defence application and be kept secret. Why dont you search "Periodically Oscillating Plasma Sphere POPS Los Alamos Physics Division". or "should google go nuclear"

in google?

[drandersw]

I already did.

The tokamak isn't taking the entire fusion budget. There are alternative magnetic configuration schemes as well the inertial confinement path.

The development of a fusion reactor has been an open internal collaboration almost from the start.

[ChrisPCrunchy]

So as a percentage of fusion funding civil & government, How much is gobbled up by those "Superconducting cathedrials" called Tokamaks over 90% I am told. When will there be a result for all those billions? If there is no result when will funding cease? If funding is ongoing without any competing program what is the incentive to achieve a solution?

The world needs this technology NOW and we cant allow the self interest of people who persue science for sciences sake to stiffle progress!

[drandersw]

The world could definitely use an economical fusion reactor which is why we are constructing ITER.

I don't understand why you are throwing out these unfounded accusations. Why bite the hand that will feed you this new source of energy?

I checked your homepage and was confused. Do you believe that you can drive a car on water? Why don't you put that water and battery into a car, feed the electrolyzed hydrogen into an engine and drive off into the sunset?

[ChrisPCrunchy]

You are getting off topic and I am sick of spamming this vid if you are interested in my odjectives with regard to automotive fuel I will be happy to discuss them via message but not here. If you work on ITER or Tokamak as you claim why dont you answer the perfectly valid questions as above. We can no longer wait for this technology to come on line. Do you realise how much radioactive waste has been dumped at sea or in collapsing salt mines or in tailings dams leaching into the environment?

[drandersw]

ITER will be completed in about 10 years and then it will take several more years before we start operating with the right mix of isotopes for fusion. I suggest that you read the ITER website or check it out here on youtube so that you can perhaps get a glimpse of the scope of the project.

[ChrisPCrunchy]

I have checked out the ITER web site. There is no projected time scale for a viable commercial facility to be up & running just more research as far as the eye can see. There isnt even a budget estimate & this is the way it has been for nearly 60 years of Tokamak research. So you tell me what has changed? We could prove or disprove the viability of Polywell in under 10 years for a tiny sum compared to ITER. Why not do both? The DOD budget is never going to get Polywell to the commercial stage.

[drandersw]

I just checked the ITER website myself and it doesn't have the time line. I don't know why, I have seen it many times.

The development of fusion power turned out to be a large undertaking but I don't think there is any grounds for criticizing the work that has been done over the years, on the contrary.

I don't know much about the Polywell idea, I just read about it today, but if it has any merit then it will be funded accordingly. We all want the energy.

[ChrisPCrunchy]

I agree fully with your last statement. Whether it is Tokamak ( which I very much doubt) or Polywell or some other type of fusion is not important. What is important is that we find the solution soon. There is no way the globe can sustain the projected population growth without a non poluting energy source NOW. Do you realise what the population will be in another 10-15 years? We cannot take the all eggs in the one basket approach. How much deadly nuclear waste will pollute the planet by then.

[drandersw]

The population of the planet will likely be limited by birth control or by wars or by famine. We will see how sensible people will be in that choice.

I think the funding profile of various experiments is a good one. It is also the case that the work done on different types of experiments complement each other. It is conceivable that the Polywell concept has not received the attention that it deserves but it seems that they already did a lot of tests with it.

[ChrisPCrunchy]

We are humans, each and everyone of us of value with hopes & aspirations that set us above all other lifeforms. Limited by birth control maybe, but wars or famine is not a solution that anyone who considers themselves human should be able to contemplate. If science is not here to serve humanity then what is its higher purpose? My greatest hero is Nicola Tesla, a man who wanted to release the whole of humanity from its plight of poverty & uncertainty through the delivery of free energy globally.

[drandersw]

We need more than just energy to sustain the population and the harsh reality is that it will be limited by something and birth control seems the most pleasant choice.

What I really want is that we begin to colonize space very soon.

Yet one more advantage with nuclear waste is that you can detect levels that are many orders of magnitude smaller than harmful, allowing a good control of containment.

[ChrisPCrunchy]

Funny you should say colonize space Prof Bussard worked for NASA on a theoretical space propulsion system using fusion of hydrogen. Colonizing space is the next most logical and essential step in ensuring human survival. As it stands now one major meteor strike or war could cause human extinction.

Nuclear waste once in the water table would prove near impossible to contain. Nuclear fission is not a solution, it is only commercially viable because the waste is left for the next generation.

[drandersw]

One advantage of nuclear power is that the energy density is so large that you can bury the waste in the ground rather than just spread it in the atmosphere. I am not feeling very polluted by radioactive waste but I once in a while inhale fumes from a diesel engine.

[ChrisPCrunchy]

Density of waste maybe but it has long lived deadly effects. There is no containment system that is designed to last the thousands to millions of years that this waste is deadly for. Eventually it will leach into the environment & its effects dont just effect the generation exposed but can cause genetic mutation & infertility that will effect all following generations. Unlike CO2 the is no natural nuclear waste cycle it is totally foriegn to nature and it is giving the planet a used by date.

[drandersw]

Regarding alternative paths to a fusion reactor, I don't know of any serious alternative to tokamaks. A critical figure of merit is the confinement time of the heat in the plasma and the tokamak excels in this respect. Many of the technological challenges of turning a tokamak into a fusion reactor are the same or more demanding for alternative concepts.

[ChrisPCrunchy]

You say you have worked on fusion all your life yet you know of no alternatives to tokamaks. It is indeed a blinkered scientific community you work within!

Look at "IEC Fusion for Dummies v5" and "IEC Fusion vs Tokamak Fusion" here on youtube. The confinment problems with Polywell have largely been solved, heat with electrostatics is no problem. More heat = higher voltage potential. Polywell is a far simpler principle that scales far better than Tokamak therefore is cheaper to test.

[drandersw]

The tokamak is the only realistic alternative that I know about and it is largely due to its good confinement.

Ions don't fuse that gladly. They like to repel each other. You have to keep them confined well enough with a small enough heat leakage to give them time to fuse.

I have heard of lots of failed ideas.

[ChrisPCrunchy]

@drandersw Including the one you are working on?

[drandersw]

I don't know enough about Polywell just yet to dismiss it but it seems to be some kind of beam fusion idea? I think I learned on page 1 of the first course I ever took why that does not work.

A fusion reactor has to produce more electric power than it consumes. In ITER we will have about 10 times more fusion power than the power needed to sustain the process. Among the huge number of technological developments we will do I can mention blanket technology for turning lithium into tritium.

[drandersw]

We are working on methods to do more and more sophisticated control of a tokamak plasma. Our models for simulating and predicting plasma behavior is improving. Diagnostics that will work and be crucial in the very radiative environment are being developed. Systems that deliver energy to the plasma are also being developed. I am missing many critical functions in this list. We are on a path to an economical fusion reactor that can become the most attractive energy source in the future.

[drandersw]

I should say that I have worked on alternatives to tokamaks myself. I have developed different forms of diagnostics and used them to measure plasma behavior. I have more recently developed control methods for tokamaks. I also run simulations and develop models. I am part of a team that helped and still help the Chinese with their fusion program and they are doing a great job in testing out super conducting technology and will do a lot of long pulse operation.

[drandersw]

I should say that I am very optimistic about the technological evolution in general but I also know about reality.

I am thinking that maybe someone can some day produce an atomic lattice structure where deuterons can diffuse in and fuse due to quantum mechanical effects kind of like mu-meson catalyzed fusion or perhaps someone comes up with a better way of producing mu-mesons or maybe some other idea will actually work.

However, putting a tokamak in the center of a reactor is our best bet now.

[drandersw]

I want to add that I think that once the tokamak in the center of the reactor is tuned in then it will cease to be of interest. Not entirely of course but the components surrounding the plasma are also a big part of the final system that has to be optimized for lowest cost of electricity.

We will in fact have a tool for lowering the confinement in the tokamak to control the burn rate.

A fusion reactor requires a control system that has no comparison anywhere else and is driving new technology.

[ChrisPCrunchy]

@drandersw When I saw the title of this video " DIII-D tokamak simulation" I expected to see an animation of billions of dollars being flushed down the toilet.

[drandersw]

NIMROD is 3-D plasma simulation. If I understand correctly, in this video it is used to simulate the plasma behavior during a disruption triggered by a too large 2/1 NTM.

An NTM is a localized helical perturbation of the plasma (called magnetic island) on a surface in the plasma where the field lines complete exactly 2 turns the long way for every 1 turn the short way.

The mode is unstable if the pressure is too high. I have developed the control system on DIII-D that suppresses this mode.

[drandersw]

I hope you will be able to understand and appreciate that we are doing the best job we can to solve the energy needs of all mankind for all future.

I hope you will be able to understand that we know what we are doing.

I let you off too easily regarding your water-driven engine. What is the deal with that? I want to know your level of physics understanding and if it makes any sense talking to you at all.

[ChrisPCrunchy]

Clearly you have no understanding of chemistry. H2O is in part a component of the exhaust gases leaving an internal combustion engine. How can you expect to start & end a chemical reaction with the same molecule & still be able to harvest energy to do usefull work? Water as an oxide of hydrogen & is in a stable low energy state. Clearly there are other reactions in my experiments & they are just the start. The desired reaction is flash pyrolysis of waste materials on board fueling the engine.

[drandersw]

Believe it or not but I have heard of people who think they can drive a car on water. I am glad you are not one of those. It was this text from your page that puzzled me:

"Plasma ignition being developed to power vehicles from water only"

Why are you accusing me of not knowing chemistry? Can you write one single comment without false accusations and insults?

[ChrisPCrunchy]

Well I find it hard to believe that someone who has Britney Spears videos featured on their home page is a Nuclear Physicist. So I treat your comments with a certain amount of sceptical criticism, I do not exactly mean to cause offence. In my opinion a problem is best solved by considering as many diverse concepts and opinions as possible. The more diverse minds and concepts embraced the quicker we can learn and discount the errors in our theories.

[drandersw]

You have a funny way of deciding who is what.

I think you should read what I wrote about fusion instead in order to decide that I am a physicist.

I agree with you regarding considering many concepts and we have.

[ChrisPCrunchy]

"I agree with you regarding considering many concepts & we have".

So why have you failed to familiarise yourself with Polywell & the work of Professor Bussard & Nebel. I would think that the concepts they have been working on has many advantages. ie a sphere presents less external surface area for heat loss than a toroid. Magnetic confinement although with ion recircualation through cusps reduces losses to within acceptable limits further improved with periodically oscillating plasma sphere

[drandersw]

They did get money to do a lot of tests. I will ask around at work and see what I can come up with and get back to you with a more informed comment in a week. My initial guess is that this is some form of wishful thinking. You can't get a lot of prompt fusion by accelerating particles onto particles but it is a way to heat. You need to confine a thermal plasma because the cross section for Coulomb scattering is greater than for fusion so the meaningful parameter is energy confinement time.

[ChrisPCrunchy]

All Polywell research funding adds up to about 18M over 10 years with ongoing funding of 3M in the last 6 years.Progress is sufficant to remain funded at this level. Funding has to be kept on a shoe string as any larger funding becomes open to further government review, when this happens the Tokamak research people submit they have the contract for fusion research & polywell is scaled back. About 290M is required to build a functioning unit to the scale that the calcs specify.

[drandersw]

I have read that before but I don't know what you mean. Are you saying that the concept can't stand up to scrutiny? I think you may be right.

I know of other failed ideas where they did not understand what the confinement would be. It is a hard topic in plasma physics.

[ChrisPCrunchy]

No it means that the Government is unwilling to fund competeing reseach as it is seen as a unnecessary replication of work. I think that the US government had also cut back finding of Tokamak which is done largely off sure now. It is good that other nations carry the load for a while as long as progress is kept open and is seen as a global effort. This is exactly what worries me about DOD Navy funding as information will not flow freely and we may lose time we cant afford.

[drandersw]

The Polywell people are not replicating what we are doing.

What matters for not losing time is that the ITER programs runs as smoothly as possible despite all the politics which seems inevitable in a big international project.

The interest in nuclear power is distributed according to what other sources each country has. France and much of Asia are very keen on fusion power.

[ChrisPCrunchy]

I know that & you know that but to those pen pushing bean counters research is research & fusion is fusion. They eat up a large slice of the budget but have no understanding of what is at stake. But getting back to the Nitty Gritty. How is it anticipated that Tokamak will yeild energy into a conventional grid. Will it drive a convention steam turbine, how will they harvest the heat without upsetting the thermodynamic equilibrium or is sufficient energy delivered through cooling of mag coils.

[drandersw]

I don't understand what you mean by upsetting the thermodynamic equilibrium.

The plasma will just sit in a steady state. The current is driven entirely or almost entirely by the plasma itself by so-called bootstrap current. Fuel is injected. Produced helium keeps plasma hot and then removed. Neutrons hit blanket modules, get multiplied, produce tritium from lithium. Super conducting coils all the while cooled by liquid helium. The heat drives steam turbine.

[drandersw]

I don't know exactly how heat is delivered to the water. Maybe there is liquid helium involved or maybe liquid lithium. I don't know exactly how the blanket cooling will be done. Not my field.

[ChrisPCrunchy]

So the heat extracted would come from the extracted helium which is cooled & cycled back to cool the coils & extracts more heat? Could it be that the "good confinment" causes an issue with heat extraction. a steam plant 20 to 30% efficiency & expensive. Is there some form of "moderator" approach with neutrons which have to be "slowed down" and lose energy by collisions with a light nucleus (like the protons in water) which directly extracts heat or is there another mechanism with the tritium?

[drandersw]

A neutron multiplier is needed since we need exactly one new tritium for every neutron so as not to run out of tritium. Since 100% of neutrons can't be used to make tritium we need lead to multiply neutrons.

If the confinement is good you don't need a lot of power to maintain the right temperature. Sufficient confinement is when the alpha particles from the fusion reactions sustain the heat. We won't have much of a problem with too good a confinement but maybe we need to tweak it down a little.

[ChrisPCrunchy]

With Polywell there was thought of power extraction via a more efficient mechanism The proton/Boron 11 reaction (PB11) produces almost no neutrons. Alpha particles are generated. These charged particles can be steered out of the reactor & can directly generate a very high voltage dc current. So you dont need a steam plant(20 to 30% efficiency ), just a tall stack of high voltage semiconductor switches & some transformers (85 to 95% efficiency) to make 60Hz electrical power for the grid.

[drandersw]

I do know about those kinds of dreams. I read all about it when I was a kid. There is also the He3-D reactor which would produce a lot of protons rather than neutrons with the alphas. That Polywell concept isn't the first I have heard of that talks about proton-Boron. Norman Rostoker in Irvine, CA has some experiment or had.

[ChrisPCrunchy]

Yes it does sound like a too good to be true solution, but who knows down the track what may be possible. It would solve much of the shielding issues as alpha particals have low penetrating depth and are less hazardous during operation should there be a component failure. Have you had any major failures or hazardous issue with experimental reactors. I would think that such issues while not being so hazardous to health as system is remotely operated, they would be none the less expensive?

[drandersw]

We need remote handling and robots to handle ITER once we go into the deuterium phase and when we use tritium and deuterium the radiation level goes up more.

When we look at the ITER plasma we have to look at light which is reflected since we won't let radiation out throw holes in the vessel.

It will be difficult to measure magnetic fields in ITER because of the radiation. One of the still relatively easy things to measure will be electron cyclotron emission which is a useful diagnostic.

[ChrisPCrunchy]

So the real hazardous part lies ahead? What about the waste products generated. Is it anticipatped that the radiation levels will be very short lived. I know the volumes of fuel present at any one time is very low. Will there be much retained radiation in the materials, components or consumable items left after extended running times as in a functioning plant or is it to early days to know?

[drandersw]

I don't know too much about the waste management but less long-lived products and not as much volatile and difficult to handle elements are advantages compared to fission.

Those who work on that aspect should know really well how it will be. There is a debate about what materials to use and many different arguments. I hear about it from time to time but I am not too involved.

[drandersw]

There won't be anything really hazardous about running ITER. What we are concerned about is not to break the machine and cause delays.

Typically at fusion research facilities we have to protect people from electrocution by power supplies or blinding from laser light or more normal accidents with falling objects or accidents with tools. We also monitor radiation levels but that is insignificant when we run D-D only in present experiments. In ITER we will have to care about radiation levels.

[drandersw]

One of the hazards would be if the the lithium comes into contact with air. We also have the tritium inventory in the system to worry about.

If the plasma disrupts due to an instability that grows out of control then we need to mitigate that and if that fails due to our inexperience or whatever then it stresses the vessel. We can only survive perhaps 10-100 failures before repairs are necessary. This is different from DIII-D where we often disrupt on purpose to study what happens.

[ChrisPCrunchy]

10- 100 failures, this is a pretty small margin of error for an experimental technology that has been running over decades. I guess it depends on what you mean by "repairs" Needless to say the type of components needed cant be picked up at the local hardware store : )

Polywell is far cheaper to experiment with. WB8 is completed but untested and already WB9 is fully funded so the Navy must like the results so far. Information on progress is however becoming restricted. A good sign knowing DOD.

[drandersw]

I will again come back with informed comments about Polywell. If it is classified then I perhaps won't be able to inform myself much more. My impression is however that it is just one of many failed ideas, perhaps based on a bad understanding of confinement.

We will use present day experiments as part of a validation procedure before we run plasmas in ITER and begin with half current, half field and commission the mitigation systems to avoid using up our estimated allowance of blunders.

[ChrisPCrunchy]

Information on progress with Polywell is becoming harder to obtain, but everything is peer reviewed. Professor Nebel is carefull in this regard. If you have ever dealt with the Gov or DOD you would know that probably over 40% of budget goes into accounting & oversight issues. I dont know how you could say "My impression is however that it is just one of many failed ideas" I can tell you right now that if the DOD has allocated funding into the future there has to have been substantial progress

[drandersw]

Again, I must say that you should not get your hopes up. We have been around the block so many times with this very kind of ideas as well as others.

[ChrisPCrunchy]

Yes but you are not talking an infant technology. In fact Prof Bussard was involved in Tokamak research prior to 1989. Polywell was first funded by DOD in 1987 & navy 1992 to present.

In September 2009, the US Department of Defense announced further funding of $7,855,504 for Energy Matter Conversion Corp (EMC2) for research, analysis, development, and testing in support of the Plan Plasma Fusion (Polywell) Project. WB8.1 is now fully funded. Why would the DOD proceed if this was a failed idea?

[drandersw]

Perhaps the answer to that one is sensitive. I don't know the answer.

If it is funded then why are you complaining about lack of funds?

There are some small experiments that we care about since they allow us to expose materials to cold plasma like we have at the edge or to study turbulence of various kinds and so on. The Polywell studies probably generate some papers about some effects. It is basic science. Maybe the Polywell is intended to be used for some entirely different purpose.

[ChrisPCrunchy]

Because due to the calculations there are certain scaling issues that will always hold back the usefulness of the WB modelling that they are presently undertaking. The size is limited by the funding & the proof of concept is limited by the size. Bussard noted that, "Thus, we have the ability to do away with oil & FFs but it will take 4-6 years and ca. $100-200M to build the full-scale plant and demonstrate it." If a fraction of the Tokamak budget was available we could have a functioning plant.

[ChrisPCrunchy]

Can you imagine trying to scale down Tokamak & demonstrate it using smaller reactor modelling. It would be impossible as you have set parameter that will allow clearance for plasmas & confinment etc etc. Yet this is what Polywell has to face. Funding kept a certain levels can be counter productive as research can be measured by lack of success without taking into account the real requirements of the science.

[drandersw]

Did he say that he can't verify his scaling predictions with an intermediate size experiment?

Overly optimistic scaling predictions based on ignorance about transport properties of plasmas is nothing new under the sun.

If the concept is sound which I doubt and if the experiment is a success then they will continue. Let us hope for the best. i am all for it and will be converted if it is a good idea.

[ChrisPCrunchy]

The concern is exactly as you stated above. The technology is being used for some other purpose or changed in some way to suit the objectives of the DOD. Think of fission and how it was weaponised before it was ever considered for peaceful purposes. What if polywell is being hijacked to make some type of a weapon instead of power generation. Sometimes the source of funding may NOT be benificial to the outcome. DOD funding makes me very uncomfortable & the outcome doubtfull.

[drandersw]

Maybe it is useful for tritium production for nuclear weapons or something.

I will look into the matter as best I can about its validity as a concept for a fusion reactor and let you know.

[ChrisPCrunchy]

Prof Bussard wanted to test further with WB7 to confirm results prior to failure of unit. Prof Nebel has improved greatly on the concept. Both came up with extremely similar estimates on scaling, time and budget estimates on a full scale plant, but information on progress is hard to obtain, eighter because of prudent professional caution which we can all understand or because of DOD secrecy. It seems to me as DOD funding increases Prof Nebel becomes less open with information on progress.

[ChrisPCrunchy]

Where did you propose we get the H3 to fuel the reaction. Very little exists naturally on earth. Have you looked into polywell yet. What are your thoughts?

[drandersw]

We don't need He3. We need water and lithium.

If we become very good in the future at confining plasmas and find a way to actually do direct conversion to electricity and want to build D-He3 reactors then we could go to the moon and suck up He3. It seems more practical to me to make tritium from lithium and D-T is the easiest reaction to make use of.

[ChrisPCrunchy]

Deuterium has to be extracted from water. I assume they would use fractional distillation, but I guess the volumes are low enough that the energy involved is not a major factor. Extraction & mining would also add to the lithium & conversion to trituim, I guess they have done the calcs on input fuel costs although isnt Tritium in short supply & therefore very expensive, I was of the opinion that D-T was mainly used in experimentation as it requires lower input energy. Have they looked into Boron

[DarkTemp0]

@ChrisPCrunchy

tritium is in short supply because it has a short half life of about 12 years, that's why you don't find it in nature. So tritium is made "as nedeed". Tritium is made by neutron activation of lithium. So basically you only need to extract lithium and activate it with neutrons from the reactor to make tritium

[Rajputo]

@DarkTemp0 And from Heavy water reactor where tritium is a by product of D2O absorption.

[drandersw]

A large fraction of recirculating power will be refrigeration of the super conductors at maybe 150 MW. Another perhaps 50 MW will go to external heating which will be needed for control purposes. The plant will generate about 1 GW electric.

[ChrisPCrunchy]

I know that the budget of constructing an experimental reactor cannot be used to gauge the cost of a final functioning unit, but if you have got to the stage where an output of 1GW is predicted how will this compare with competing power generation facilities in terms of initial construction, ongoing service life issues, input fuel expenses & availability. Is it at the stage where there are any estimates on this, because it is often at the final hurdle where any new technology fails.

[drandersw]

Our work is aimed at an economical reactor. This is not like the Apollo project where the goal was to reach the moon at any cost. Having said that, it is still very hard to know just yet exactly what things will cost and how far into the future the technology has matured and other energy sources can't compete. I believe it will become the most attractive alternative eventually and it is at any rate important to have this alternative available.

[ChrisPCrunchy]

OK. Thanks for having an open mind and all the Info, it is indeed a fascinating subject that anyone with an interest in science would like to have an involvement in. Sometimes it is hard to get your head around all the issues involved, not just science but politics, finance, etc etc. Enjoy your New Years break. Let me know if you find out anything interesting and take care. Regards ChrisP

[drandersw]

Most of the energy is in the neutrons. The lithium blanket is heated by the neutrons and cooled by water and that is where most of the heat comes from that drives the steam turbine.

[ChrisPCrunchy]

Oh I should have read further before comment. So what is the exhaust end products how are they extracted and is there any hazards with short lived radiation? or shielding from radiation during operation and reduction in component life span due to these issues?

[drandersw]

Component life span due to these issues is a major concern. We are now thinking very seriously about what it means to have a material wall right next to something which is hotter than anything with thousands of light years. :-) However, it can be done because it is the heat flux that matters and not the temperature. The plasma is very thin and the pressure a few atmospheres. A fusion reactor is inherently safe since it recycles the fuel within seconds so only a small reservoir is in the reactor.

[drandersw]

We are developing ways to detect, avoid, mitigate off-normal events that can happen if a power supply fails for instance. We are developing ways to shut down the plasma rapidly as a last resort. One method is to shoot an ice bullet into the plasma with a high speed gun. It is kind of like a rifle.

[drandersw]

One of the things we are working on today is how to control the edge plasma to extract heat without melting the inner wall, i.e. maximizing its life time. There is a type of local edge instabilities ELMs that get unstable if the pressure gradients gets too large at the edge. We can deal with it by applying a small field perturbation or by dropping pellets of frozen fuel in the plasma.

[drandersw]

Another one is control of the islands I mentioned. It may be advantageous to control them at the expense of more circulating power if we can go to higher pressure and more fusion power. If not then we can still use them to control the profile of pressure to keep us at an optimum condition.

[drandersw]

The tokamak has the best confinement or possibly stellarators but they have lower beta = thermal pressure/magnetic pressure. At least that is the conventional wisdom. I am pretty sure that the Polywell confinement is a big joke but we will see.

Are you familiar with the Lawson criterion? The triple product nTtau_e?

We have come a very long way since those early considerations. We are now dealing more and more with real world details and it will only increase. We are onto the nitty gritty.

[ChrisPCrunchy]

US Navy costs expended to date in this program have been approximately $18M over about 10 years(2/3 in last 6 years). The Navy needs to keep budget at or below this level or it is open to further government review. Once this happens the people conducting Tokamac research submit that they have the contract for fusion research & EMC2 & Polywell are shut down.

[Spitfireseven]

You'd like the Tritium and deuterium to do what you want them to do. But at a higher temperature, 10million plus they obey rules that only they understand. Even they do not pretend to predict where they will go. But, you can ask them. Be nice about it. You might even get an answer.

[hardcorro]

i wish to know more about it