[zapkitty]

Alburton wrote: According to Mike B Hopkins:…

Hopkins conception of DPF neutron sourcing was both
outdated and based on a misunderstanding of the LPP
experimental goals…. apparently aggravated by aggravation
with LPP, but you’d have to ask him about that 🙂

The LPP paper in question, the one describing record DPF
temperatures sufficient for hydrogen-boron fusion,

[em]Fusion reactions from >150keV ions in a dense
plasma focus plasmoid[/em] in Physics of Plasmas
19, 032704 (2012)

… answers the question of ion beams as the sole source for
the neutrons: while some neutrons do come from the beam
the bulk of the neutrons – approximately 60% – come from a
confined plasma.

This is discussed thoroughly in the section titled

III. DATA ANALYSIS

…specifically in parts…

B. Neutron energy isotropy
C. Neutron flux anisotropy
D. Timing of neutron emission and beams

And for some charactization of the plasmoids see part

E. Size and density of confined plasma

As for investors… there are investors, substantial ones and
middling ones and there will be more in the coming year, I
believe 😉

And the vulture capitalists, inequity infirms and
exxonmobilian pseudopods…? They lurk at the threshold,
meeping their gibbering cries for backdoor control. Would
you expect otherwise?

Edit: Huh… Still an Admin? I’ve been ill, and it’s not wise to
leave a superadmin account lying open for months. Should
lower my privileges a bit, I think 🙂

[zapkitty]

ikanreed wrote: I know we’re all gung-ho for the value of aneutronic fusion, but all fusion wins if any commercially viable fusion reactor hits the market. Suddenly no one can claim that fusion is “always 50 years away” anymore.

Wouldn’t count on that occurring on its own. Our self-proclaimed “uber elites” are very good at encouraging or even arranging situations where a not-so-good solution (such as bomb-capable commercial fission power plants) become treated as the only “viable” solution even over manifestly superior options.

I know that the various D-T projects are proceeding with the best of intentions and I do wish them success.

But that doesn’t change the simple fact that neutronic fusion is the PTB’s third choice for controlling access to baseload power… the first two being fossil and fission.

While any neutronic success will be good news overall, the aneutronic projects will still have to fight the headwind of a new status quo.

[zapkitty]

fixed your quotes up above

Tulse wrote:
Once you need [em]any[/em] sort of steam-turbine-generator setup, that presumably wipes out almost all the capital savings, right?

Yes, the steam turbine gear, generator, supporting waterworks and the maintenance for it all are the largest portion of the costs of building and operating a current fossil or fission power plant.

And, as with a fission plant, a D-T fusion plant would also use its neutron output to heat water to create steam to turn turbines to power a generator etc. etc.

This has been regarded as the de facto standard design for fusion reactors as the D-T reaction is the easiest to achieve and ~80% of the energy output of the D-T reaction goes into the neutrons produced.

Tulse wrote: Sure, you might be able to get away with a smaller turbine and generator, but I would think the main cost is the physical plant and gear associated with [em]any[/em] sort of steam generation.

One way around it would be to discount the neutronic output of the D-T reaction as a loss… to only use it for breeding tritium from lithium.

But this would require a high gain factor from the reactor. Let’s say the reactor has an energy gain factor (Q) of ~10… ITER is expected to have a Q of ~10 and the follow-on DEMO project a Q of maybe 25.

So with a Q of 10 then 1 MW of input would get you 10 MW of output. That would be about 2 MW of directly convertible fusion products and 8 MW of neutrons.

(Unlike steam turbines the various direct conversion processes can be [em]very[/em] efficient. 80% efficiency is a reasonable goal.)

So if you discount the neutron output then the 2 MW left over becomes ~1.6 MW after direct conversion.

Your gain factor of 10 becomes a factor of 1.6… but you get rid of the expensive, bulky and costly to maintain steam-related gear.

The tech details in the release are almost non-existent but it’s possible that this approach would be worthwhile. And maybe Helion figures they can finesse these ratios a bit.

… so that pdf mentions a ~50 MW reactor… but is that the total fusion output or is it 50 MW electric delivered to the grid?

50 MW total output would get you 8 MW to the grid… like an FF module but with the added expenses of intense neutron flux, tritium breeding and handling and highly radioactive components in the waste
stream.

If it’s 50 MW to the grid then the raw fusion output would be in the 310 MW range … with ~248 MW worth of neutron flux to just breed tritium, radioactivate the burn chamber and, of course, to be converted into heat and rejected from the reactor somehow.

Tulse wrote:
In other words, if they’re not fully direct generation, I’m not sure how they can claim that there is any significant capital savings.

If they intend to direct convert what they can, and just use the neutrons for tritium breeding, then the description could make sense.

[zapkitty]

vansig wrote: http://nextbigfuture.com/2014/07/helion-energy-plans-to-enable.html

Helion’s “Fusion Engine” (FE) concept is a neutronic D-T design… a standard deuteriun-tritium burner.

In other words while it would be an immense improvement over fission it’s still “dirty” fusion which needs a radioactive fuel (tritium) and would produce high-powered radioactive waste via neutron activation of its burn chamber components.

Their current PR push can be a bit… misleading. Unless it’s parsed carefully you could almost swear it was an aneutroic fusion design. 🙂

Fusion is clean, safe, and generates no hazardous byproducts

D-T fusion is safe, vastly safer than fission, and it doesn’t leave massive amounts of white-hot radioactive fuel byproducts behind… but it will leave a trail of very radioactive burn chambers behind.

Like all neutronic fusion waste these will be highly radioactive, lethally so, but thermally cool and inert with a hazardous lifetime of maybe ~300 years … instead of the hazardous lifetime of many thousands of years of fission waste.

Indeed, one of the design features of the FE is that the burn chamber is separate from the plasma injectors and thus can be replaced as a module when needed.

Fusion energy is converted directly to electricity, eliminating capital costs

Apparently an MHD design driven by the fusion products in the burn chamber reacting against imposed magnetic fields.

Speculation is rife on this part but it seems that if they’re omitting the steam cycle totally they’ll give up a large portion of the possible fusion power output in return for much cheaper and more compact direct conversion gear buit into the reactor itself.

But it seems more likely that they’ll use MHD to tap the fusion products for enough energy to power the device itself… but still needing to have a separate steam cycle for net power output to the grid. If that’s the case then perhaps a more accurate phrasing would be “eliminating [em]some[/em] of the usual capital costs associated with neutronic fusion”

Energy Generation -Fusion plasma is converted to i) direct energy ii) fuel for further operation

This implies a standard D-T setup… breeding tritiium from a lithium blanket surrounding the burn chamber.

[zapkitty]

wizz33 wrote: https://soundcloud.com/yumas-1/013-crowdfunding-science-projects-with-cindy-wu-y-combinator-alum

https://experiment.com/

crowdfunding
pleas listen and check for the last 20k

Do you mean check these out as options for the last 20k of LPP’s Indiegogo crowdfund target?

I wonder if the LPP site has a place that shows current crowdfunding totals?

[zapkitty]

A side note: Is LPP going to cover the LPPX history? The FFS had that
for a while but the coverage lapsed. It shouldn’t stay dormant, I
think. That total history available in articles and pics detailing both
advances and setbacks… that can be both interesting and persuasive…
as well as a good counter to arguments that FF is a scam
or that we’re delusional. Scammers don’t like leaving a detailed history
and delusional histories can’t stand up to scrutiny.

But is FFS the place for that? Or would it be better situated over at LPP’s site? .

[zapkitty]

Starting on this now that the crowdfund drive is over.

Any objections to a full conversion from expression engine to
wordpress?

The current goal is for a landing page, an “Intro to FF” page, a news
page, the forums, and a page for aneutronic-related articles.

My current plan for the landing page is for a header area that’s a
banner slideshow, below which is to be a full-width bar, a “function
bar” that is relatively thin, containing social media icons and a site
search form as well as other oddments.

Beneath that should be a sidebar on the left and a news area on the
right. The news area will in turn be split top and bottom between notices
of recent news articles above and notices of recent forum posts below.

Beneath it all will be the footer for cleanup and legalese.

The goal is to cover what the *[em]FFS[/em]* site needs to cover in an
accessible style without excessive complexity.

And there are a number of mobile-ready themes along these lines that
can be easily adapted to our needs while still being usable on a
classic desktop system.

The front page or the landing page from the top: The banner

I’m thinking that the banner should have 3 slides in rotation, each
with a short phrase about FF or the implications of aneutronic fusion
along with appropriate art. As the concepts of FF and aneutronics cover
a lot of territory each page visit will load a different set of three
slides from a list of such. The choice of which 3 particular slides
from the list will be random for no-cookies visitors or in rotation for
browsers with cookies enabled.

That banner is to be the eyecatch and the slides should be in text
and image(s) so that the banner can load quickly and be accessible.
3 slides at a time will give us space to add a 4th slide when it is
needed… say, for a specific event or campaign.

Which phrases to use? The best short phrases that encapsulate the
the various aspects of Focus Fusion, aneutronics and the FFS. They
should be factual and yet brief… enticing and inviting further
exploration. Each slide can link to a related topic on the site. This is
one area where the input of the membership will be needed and greatly
appreciated.

Here are some examples of what sort of phrases I’m thinking of. In
order to avoid prematurely singling out specific FF-related phrases
I’ve provided some examples that are actually bits from various old SF
movies… so please pardon the disconnect 🙂

[em]”8000 cubic miles of klystron relays” [/em]
pic(s) of the Great Machine from Forbidden Planet.

[em]”We sighted it moving towards Earth less than two hours ago”[/em]
pic(s) of asteroid Flora from The Green Slime.

[em]”Independent action increases on a 73-degree tangent”[/em]
pic(s) of the Courier’s floating head from Not Of This Earth

[em]”We go into the nest and find out”[/em]
pic(s) of the nest from Them.

… substitute FF-related phrases and art and that should get the
concept across.

Next: the function bar
… sort of a junk drawer right now 😉

Next: the sidebar.

Below the function bar there should be a sidebar on the left
with a listing of direct access links to various site areas. The
sidebar should be headed by a compact version of an improved FFS logo.
This can lead to a new “Intro to FF” slideshow, one that gives a good
introduction to what both FF and aneutronic fusion are and why we
support them. This intro probably would be derived from the current
landing page and the Indiegogo stuff but greatly clarified and of
course with text components instead of all graphics. (For right now tho
we can cannibalize the one on the current front page.)

Below the “Intro” header the the sidebar should have links to “About
the FFS”, the news page, the forums, the aneutronic-related
articles page… and what else?

Next: the recent news area.

This should be a largish part of the page.
The news area should have excerpts from the latest news
articles in the news section, linking to those same articles. Below
that should be a listing of the latest forum posts, again linking to
those posts.

And then the footer.

This plan should make the site and especially the new front page
both more accessible and more informative than the old versions.

So that’s the outline. What do [em]you[/em] think of these concepts?

[zapkitty]

JimmyT wrote: Up until now the assumption has been a fusion generator with a pulse rate of 200 Hz.

Focus Fusion units are intended to be drop-in replacements for existing infrastructure… wherever and whatever that infrastructure might be. This enables FF implementation [em]without[/em] forcing changes in standards or requiring massive stranding of current grid assets.

JimmyT wrote: Then conditioning the electricity to 60 Hz and blending it in the grid with other 60 Hz electricity.

It sounds like you’re thinking AC and the raw output of a unit will be in HVDC. That means that there will have to be conversion at each unit or cluster of units regardless of local electrical standards and thus the output of a particular unit will be tuned to whatever is needed at that particular locale.

And so the simple and economic answer to grid improvement via Focus Fusion is to install FF units wherever needed, which will eventually be most everywhere, and to adapt the [em]local[/em] grids to robust distributed modes of operation as we go.

This is already happening in fits and starts with the arrival of alternative energy sources and FF joining the party will only accelerate the process… big time 🙂

Long overdue infrastructure upgrades in places like the U.S. will be much easier to undertake that way. The FF units will more than pay for themselves and thus the sheer damn [em]cheapness[/em] of aneutronic fusion will cover an awful lot of grid improvements and upgrades.

[zapkitty]

nemmart wrote:
Oh come on Zap, why would you assume that the only way to increase the fusion output beyond 66 KJ is by changing to D-T fuel?

Would you believe it was your statement of the need to increase the fusion gain by a factor of 6? 🙂

nemmart wrote: There are more parameters that can be tweaked than just the fuel…

But they all amount to increased heat in the core… unless you’re postulating some currently unknown mechanism that will lead to a far more efficient fusion process than is currently envisioned?

While there is some flexibility there, some leeway towards a core that is a bit hotter or a bit cooler, there is just not near enough margin to septuple the output without melting the core.

[zapkitty]

nemmart wrote:

The thermal output of an FF unit operating at 200 Hz has been estimated at ~7 MW thermal… doable, but pushing things a bit.

Initiating each shot requires 100 KJ from the capacitors. If the conversion efficiency is low (say 40%) then you won’t get enough energy from each shot to recharge the capacitors for the next shot. And the shots/sec is irrelevant.

The question is core temperature and so the results will be the same whether you increase the shot rate or the energy per shot.

The final set of beryllium electrodes will be quite a bit smaller than the old copper and current tungsten designs. Less mass and closer to the plasmoid. Increase the temperature too much [em]and the anode is going to be slag.[/em]

nemmart wrote: A plan B designed around a lower conversion efficiency would require far more energy from the fusion reactions, something like 400 KJ per shot instead of the planned 66 KJ.

That would, of course, mean switching from an aneutronic to a neutronic process. Switching from pB11 fuel to D-T fuel… from hydrogen-boron to deuterium-tritium .

And that just means that the anode will not only be slag but the entire FF core will be highly radioactive for centuries to come. Not very good for the FF project.

The temptation of D-T… the low-hanging but extremely radioactive fruit of the fusion fuel tree.

Interesting aside: EMC2’s Polywell project recently seems to be trying to use the prospect of D-T fuel to lure in investors… which seems odd since D-T’s intense high-energy neutron flux would quench the HTSC coils a Polywell power generator would need to function.

[zapkitty]

nemmart wrote: If the onion and ion beam capture hit the 80-90% targets then everything will be just peachy.

The high efficiency estimates are a result of the known physics.

nemmart wrote: It’s not too difficult to imagine a scenario where the fusion works, but the engineering to hit the 80-90% conversion efficiencies fails.

The efficiencies could be lower by 5-10% each, depending on how each side sorts out, and FF would still be a viable electrical power source.

nemmart wrote: To me, this seems like a significant risk to the project.

Not really. I’m not saying it’ll all be smooth sailing but the physics of both the ion beam and the x-rays are known quantities. It’s just that we are used to converting electricity into ion beams and x-rays rather than tapping them for power.

nemmart wrote: So why not have a plan B in place?

That would be fine… as long as the plan B doesn’t involve thermal-electric conversion.

nemmart wrote: I would advocate that someone on the LPP team or who knows what parameters can be tweaked should be looked to see if there is an alternative configuration that produces more fusion power per shot.

This seems to be a fairly common misconception… the power output of an FF unit is primarily determined by its pulse rate. Any increase in individual shot power can be approximated by increasing the pulse rate.

And the maximum pulse rate is governed by anode cooling. The thermal output of an FF unit operating at 200 Hz has been estimated at ~7 MW thermal… doable, but pushing things a bit.

A substantial increase in either shot power or pulse rate would both end up with the same result: a corresponding rise in temperature and a slagged core.

nemmart wrote: We know that a heat engine can achieve 40% efficiency

… errrrrrrrrrr… not quite. Those kinds of thermal efficiencies are achieved at the expense of very high operating temperatures. Temperatures in the thousands of degrees C.

The most anyone has ever postulated for the output of an FF cooling stream is at ~700-800 degC… i.e. maybe 20-25% thermal-to-electrical conversion efficiency. That’s game over for a thermo-electric FF, I’m afraid.

… still would be a great x-ray source, though.

[zapkitty]

Impaler wrote: This the the kind of rubbish an administrator should be deleting from the forums, not posting. It’s not even relevant to BB theory.

Patientman isn’t a system administrator, but [em]is[/em] a paid member of the FFS. In forum terms this just means that they have access to some publishing tools (which paid members hardly ever use)

But the default setup of the ExpressionEngine installation gives anyone with those (limited) privileges the confusing title of “Administrator”

… yet another reason why we’ll be migrating the forums to a better engine…

As the thread isn’t about plasma cosmology I’ll move it to the “Noise” section.

[zapkitty]

Tim1 wrote:
Nice chart.

I believe that FF Sankey diagram has been updated:

Edit: See the attached pdf for the more recent full size version.

.

Tim1 wrote: What are the prospects of getting more than 66 kJ of gross fusion energy per shot? That would make conversion efficiency less of an issue.

Yes, a bit of an increase would be good… but if you up the gain too much then you run into the same problem as if you’d increased the pulse repetition rate: too much heat for the anode to handle.

Attached files

Sankey.pdf (564 B) 

[zapkitty]

Hello, NortySpock, and you’ve come to the right place. Welcome to the forums!

The 5 MW per Focus Fusion (FF) unit seems pretty firm at this time. But that’s perfectly suitable for a distributed, modern, disaster-resistant power grid.

The current gigawatt-class power plants are a convenience for those that own the plant and/or the fuel supplies… for the rest of us, not so much. Especially when one plant going down puts the whole system under critical stress.

But if a location such as a large factory needs more than 5 MW on hand? The units will stack easily… and cheaply 🙂

As for why 5 MW? The power output is primarily determined by the repetition rate, 200 hz for 5 MW, and is bounded by two limits: cooling and heating.

A. Too much slower than 200 hz and the vaporized boron in the fuel will plate out and coat the interior of the vacuum chamber. Not good as things grind to a halt.

B. Too much faster than 200 hz and the anode, the central electrode, begins to melt. It will be cooled by helium under pressure and while that should be doable for 200 hz it probably couldn’t be pushed too much further.

As for using D-T and other neutronic fuels? While technically it’ll be possible to use such in an FF unit but you’d run into three immediate problems:

1. Fuels such as D-T release their energy primarily as neutrons, which will have to be used heat water to make steam to tutn (very expensive) turbines in order to generate power.

2. The FF unit can only run at a few hundred degrees Celsius, and that’s with the helum cooling. That’s well below what’s needed to run those expensive turbines efficiently… but trying to crank up the power will just melt your electrodes into slag.

3. … and the slag, the vacuum chamber and all the surrounding gear will be highly radioactive for a long time.

The direct conversion made possible by aneutronic fuels skips all that, even if the bar for breakeven is set much higher.

[zapkitty]

rashidas wrote: Whenever I try to log in to Focus Fusion forums I get a message not to click on the website on my office computer. I get a warning that this website is dangerous and leads to a phishing attack. Can anyone sort through this problem?

We changed web hosts recently, and found that our new IP address was already blacklisted in some places. It happens. If you could find out which blacklist(s) your office uses I can try to get the blacklist cleared.

A quick check only shows mailpolice.com blacklisting us. I’ll see what I can do about them but there’s no guarantee that they’re the site your office system checks with.

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