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Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

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Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#221

Post by DennisP »

willis936 wrote: post #126
rcollyer wrote: post #63

Earlier quoted context omitted.

Only the helium nucleus is formed as part of the fusion reaction, so it starts off being positively charged, and not later stripped of its electrons. That, in principle, creates a current which can be used almost directly.

Well, it creates a region in space with a high charge density that can be accelerated to a plate that has a voltage applied to it which it bumps into which then causes a current. Importantly, this doesn't have to happen in the reactor vessel. The charged gas can be pumped somewhere else.

It does have to happen in the reactor vessel. It's not just that it's a charged gas. It's that it's a charged gas which is exploding with almost 300 kWh of energy per shot.

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#222

Post by pfdietz »

I am very skeptical of this approach.

The big problem I have is the direct conversion approach being suggested. The idea, as I understand it, was that the target is placed at the center of a large sphere, and is negatively charged, so the alpha particles from fusion slow down as they go up the potential to the surrounding spherical collector.

You see the problem with this, I hope. The violent and energetic event at the target will produce gas and plasma, and lots of free electrons. What is stopping that from shorting out this megavolt vacuum capacitor?

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#223

Post by pfdietz »

rklaehn wrote: post #197
NortySpock wrote: post #187

Earlier quoted context omitted.

Wouldn't it produce high-velocity charged particles? Thus you would capture the energy with a "reverse coilgun", "regeneratively braking" the particles down to a non-relativistic speed, rather than just using them to charge a capacitor plate.

Once the capacitor plate has a voltage in the range of the kinetic energy of the particles, this is exactly what will happen. The particles convert their kinetic energy into electrical energy by rolling "uphill" against the electric potential.

And all the free electrons produced in that target are helpfully just sitting there, right?

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#224

Post by pfdietz »

anonuser123456 wrote: post #162
ncmncm wrote: post #145

Earlier quoted context omitted.

There is no actual expectation of ever getting useful power generation from magnetic confinement fusion (ITER, Tokamak): it has always been, instead, a jobs program for high-neutron flux physicists, to maintain a population to draw on for weapons work. p-boron fusion is interesting as a possibly practical energy source. The hurdles are a matter of engineering and finance, not fundamental design flaws. But it's useles…

SPARC is not ITER. It's seems bizarre to ignore the impact HTS tape would have on the plausible operation of MCF.

ARC's power density is only 40 times worse than a PWR, rather than 400 times worse like ITER.

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#225

Post by toptal »

Can someone provide a list of how much each item that is relevant to this technology is likely to cost?

I’d really like to know how much each laser, pellet, metal case, etc will likely cost in this and how difficult it will be to create each one.

I would have to imagine that these lasers will be the most difficult part of all of this. It will also be good to know how long each laser lasts and how much power they require to operate effectively.

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#226

Post by eloff »

LaMarseillaise wrote: post #204
ttul wrote: post #201

Earlier quoted context omitted.

I'm not an expert at all, but I follow news about fusion energy with keen interest. Getting to conditions where fusion reactions can take place requires modeling the physics with supercomputers. I think the physicists have a handle on the software required to do that modeling; they also have access to the computers. I think if you have a software background and want to contribute, you should consider applying for a j…

I think it must be mentioned that in addition to fission and fusion (ITER) work, General Atomics is the creator of the MQ-9 Reaper, which is commonly used for drone strikes. A software job at this company may involve work on these aircraft.

And that's bad because drones are evil? I'm sure I don't agree with a blanket statement to that effect. They're a tool of warfare and I don't see how they're particularly worse than other ways of killing your enemies. I can think of a few ways they're better.

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#227

Post by lovemenot »

eloff wrote: post #226
LaMarseillaise wrote: post #204

Earlier quoted context omitted.

I think it must be mentioned that in addition to fission and fusion (ITER) work, General Atomics is the creator of the MQ-9 Reaper, which is commonly used for drone strikes. A software job at this company may involve work on these aircraft.

And that's bad because drones are evil? I'm sure I don't agree with a blanket statement to that effect. They're a tool of warfare and I don't see how they're particularly worse than other ways of killing your enemies. I can think of a few ways they're better.

While you may not agree, you can surely recognise that others may appreciate the heads-up. I can easily imagine some people may be pleased to work on fusion, but not on drones.

Your parent merely notified us that more than one type of product is in development at that company and one that is not fusion is specifically designed to kill people.

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#228

Post by superkuh »

detritus wrote: post #2

This seems.. too good to be true? I don't have the Physics chops to untangle the likelihood of this tech and the credibility of the process and its authors, so I'm hoping the HN crowd will be able to pad out the story behind this. Certainly, from my layperson's perspective, their website isn't exactly encouraging... https://www.hb11.energy/ - ed re: last line - "books and covers, and all that"

After reading the article and skimming some of the innumberable references (the article is all references) it seems like the unobtanium part of using laser pondermotive force to accelerate blocks high density plasma from solid state is that the laser "contrast ratio" has to be very high. In the paper it cites many failed replication efforts to use this particular laser pondermotive force due to lack of "contrast ratio".

I have no idea what "contrast ratio" means, it isn't defined, and isn't in the references. Does anyone know what "contrast ratio" means in terms of high power pulsed lasers?

edit: To answer my own question, ref: https://cdn.intechweb.org/pdfs/24813.pdf

> the laser pulse contrast ratio (LPCR) is a crucial parameter to take into consideration. Considering the laser pulse intensity temporal profile, the LPCR is the ratio between its maximum (peak intensity) and any fixed delay before it. A low contrast ratio can greatly modify the dynamics of energy coupling between the laser pulse and the initial target by producing a pre-plasma that can change the interaction mechanism.

It seems to be how fast the laser turns on, the rate of change of intensity.

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#229

Post by vilhelm_s »

wtracy wrote: post #170
acidburnNSA wrote: post #76

Always happy to see people doing new and interesting stuff with fusion. I got into nuclear technology because of ITER back in the early 2000s. Worked on it continuously (mostly in advanced fission) ever since. > "The timeline question is a tricky one," he says. "I don't want to be a laughing stock by promising we can deliver something in 10 years, and then not getting there. First step is setting up camp as a company…

> The fifth step is to attach it to power generating equipment The part that jumped out at me as strange is that they claim their process generates electricity "directly" without having to drive a turbine. Supposedly they produce helium cations, and that can drive a circuit. Can anybody comment on whether that makes sense?

There are various proposed schemes for doing so: https://en.wikipedia.org/wiki/Direct_energy_conversion

In principle this could be more efficient than a heat engine, although the Wikipedia page seems to say that an "economically feasible" version would have around 60% efficiency, which is the same as a combined-cycle power plant.

Re: Radical hydrogen-boron reactor leapfrogs current nuclear fusion tech?

#230

Post by wchar_t »

acidburnNSA wrote: post #113
pier25 wrote: post #102

Earlier quoted context omitted.

Good answer! > Same can be said for fission, but it only powers 5% of the world due to what can be called complications But weren't these complications obvious before deciding to scale up fission power plants? The ones I know about: - Radioactive waste - Risk of failure - Unavoidable EOL

Certainly the generation of radioactive material in fission plants was considered potentially fatal all the way back to Fermi, who said way back when: > It is not clear that the public will accept an energy source that produces this much radioactivity and that can be subject to diversion of material for bombs. However, the nuclear fission industry has arguably shown that it can technically manage radioactive wastes w…

> But the public largely still doesn't like it.

That's really sad.

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