[Timo]

Brian H wrote:

I’m currently resigned to a 1 meter water jacket and the same caps, maybe even switches, that LPP’s using for my sketches.

One meter radius ball would weight roughly 4.2 tons, and that doesn’t leave much space for actual equipment. Not quite car material. Does it have to be that big? Is there a better material?
It’s a 80-100 cm. shell, not a ball. The calcs are somewhere on the site; try https://focusfusion.org/index.php/forums/viewthread/91/#346 (from 2006).

I guessed that it is not a ball, but ball is a shape with smallest possible volume to surface area and as such also weight. So I minimized it right there, and still got 4.2 tons of weight. Any other shape and it weights even more. Water is heavy stuff.

No, Timo. Its walls are only 80cm thick, hollow, diameter about a meter internally. Imagine if it was 1 cm. or 1 mm. thick. How much would it weigh? It’s not a solid/continuous sphere, it’s a container.

80cm thick is not one meter water jacket. It’s 80cm water jacket. Anyway any other shape than perfect ball weights more. 1mm thick would obviously weight less, but then it would be 1mm water jacket, which is not enough. You just increase the weight with any other shape (there is obviously the structural integrity issue, which probably require less spherical shape to reduce structural stress and weight of structure itself, probably a kind of arc, but you get the picture).

[Timo]

Brian H wrote:

I’m currently resigned to a 1 meter water jacket and the same caps, maybe even switches, that LPP’s using for my sketches.

One meter radius ball would weight roughly 4.2 tons, and that doesn’t leave much space for actual equipment. Not quite car material. Does it have to be that big? Is there a better material?
It’s a 80-100 cm. shell, not a ball. The calcs are somewhere on the site; try https://focusfusion.org/index.php/forums/viewthread/91/#346 (from 2006).

I guessed that it is not a ball, but ball is a shape with smallest possible volume to surface area and as such also weight. So I minimized it right there, and still got 4.2 tons of weight. Any other shape and it weights even more. Water is heavy stuff.

(which reminds me a case when I explained someone the power of tsunami by giving him mental image of one cube of water coming at 50kph to the wall of a house and telling that is basically same as small car hitting the same place at same speed, and that is just tiny one meter high wave. His face was worth looking when he realized what that means).

[Timo]

zapkitty wrote: And thus the notional DPF “box” can be described as 3m x 2m x 2m… if you work within those constraints for the time being you’ll be less likely to be taken by surprise…

… and why a fusion-powered passenger car? If aneutronic fusion is proven then Chevron will have no choice but to relax its death grip on large NimH battery applications… or they won’t have any options left at all except the auction block.

Just hypothetical mind game. How small can we get.

Maybe passenger cars are out of the question for some time, maybe forever, but just one of those 5MW 3x2x2m boxes would power bigger boats and ships just nicely. Other thing I could imagine is a big cruiser-like blimp (airship, dirigible) with nearly infinite range. Would you like to go air-cruising in luxury blimp? I would. Cross-Atlantic flight that takes several days, but with comfort of the luxury ship. Maybe heavy-duty very large range helicopters? 3x2x2 is small enough to fit in locomotives several times over, so trains definitely get that benefit. No more expensive electric overhead wires. This can revolutionize much more than just household electricity needs.

I can’t imagine the savings of the fuel costs for bigger cruisers and cargo ships.

Passenger cars would obviously be battery electric vehicles powered by distributed “grid” of fusion reactors for a long long time unless/until we can get the actual reactor small enough to fit into car.

[Timo]

Aeronaut wrote:

I’m currently resigned to a 1 meter water jacket and the same caps, maybe even switches, that LPP’s using for my sketches.

One meter radius ball would weight roughly 4.2 tons, and that doesn’t leave much space for actual equipment. Not quite car material. Does it have to be that big? Is there a better material?

[Timo]

Aeronaut wrote: The Focus Fusion test reactor is roughly the dimensions of a 36 cup coffee pot, so it can go into lawn mowers if you can get the shielding, capacitors, vacuum pumps, and other support systems small enough and light enough.

That sounds nice. 5MW car engine 🙂 Even if it were just very heavy duty trucks, it would still be great improvement over current ICE fossils. Definite ship powerplant material.

I think the shielding is the major problem to miniaturize, others are more or less just engineering challenges.

If I understood physics right you need something that has high hydrogen concentration to capture neutron radiation which basically means water, that that is something that weights a lot. Tried to find some measurements about capacitors but didn’t find any. 25-50kV doesn’t sound much, but IIRC those capacitors are quite big. That might be another not so minor challenge.

[Timo]

Brian H wrote:

What I actually did mean is there a physical limitation to how small we can get. This first generator FF generator is probably quite a lot too big for for example cars, but can it get that small even in purely theoretical level? Lets say 250kW FF reactor?

Multi-hued Dragon drive? 🙂 Seriously MHD usually means magneto hydrodynamic drive IE. boat motor, I think you mean MPD = Magnetoplasmadynamic drive.

Size: AFAIK, the sizes of DPF devices are constrained by the minimum physics requirements of generating a plasmoid. I’m not sure if it can be made that low-powered.

IOW it depends of how small equipment is capable or producing pinch that is powerful enough to produce practical amount of energy. I don’t think plasmoid itself is constraining factor. That is if I have understood the physics right (which is not at all sure thing).

Brian H wrote:
MHD — well, you’d better let the USAF know it’s misusing the term!

I found out that MHD is used for magneto hydrodynamic systems in systems that include fluid dynamics after posting. “hydro” refers to fluids in general.

Brian H wrote: I found the paper:
http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA446973

The page link above is to the abstract, and it contains a link to the original full report: http://handle.dtic.mil/100.2/ADA446973

Be warned: this downloads a small PDF file without an extension. You’ll have to edit the filename to add “.pdf” to get your software to read it.

Works fine with FF 3.6.12, no need to add “.pdf”. This is what I got: http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA446973&Location=U2&doc=GetTRDoc.pdf

[Timo]

Brian H wrote:
As to going orbital, there are some old Air Force studies of DPF as an SSTO power source, using MHD drive. I believe the conclusion was that there was power to spare. If so, theoretically FF is the basis of a sci-fi one-ship-does-all vehicle! If I can find the links, I’ll post them.

Found one PDF which has couple of interesting references that might help your search: “http://namcub.accela-labs.com/stories/pdf/Advancements in Dense Plasma Focus (DPF) for space propulsion.pdf”

I don’t have time to search further just now, but this definitely is interesting.

[Timo]

Brian H wrote:
For trucks, consider that the total weight of the FF generator, including shielding, is expected to be about 2 tons. I don’t think you get it under the hood; it would have to be a special configuration.

What I actually did mean is there a physical limitation to how small we can get. This first generator FF generator is probably quite a lot too big for for example cars, but can it get that small even in purely theoretical level? Lets say 250kW FF reactor?

Brian H wrote:
As to going orbital, there are some old Air Force studies of DPF as an SSTO power source, using MHD drive. I believe the conclusion was that there was power to spare. If so, theoretically FF is the basis of a sci-fi one-ship-does-all vehicle! If I can find the links, I’ll post them.

Multi-hued Dragon drive? 🙂 Seriously MHD usually means magneto hydrodynamic drive IE. boat motor, I think you mean MPD = Magnetoplasmadynamic drive.

[Timo]

Brian H wrote:
Timo, is that you? Same Timo who infests and informs over at TeslaMotors forums? Welcome, buddy!

Yes it is me. I finally decided to join after lurking quite a while. Actually I got my “membership” due a donation, I didn’t know it would lead to that, but here I am.

[Timo]

The_Programer wrote: I wasn’t thinking of airplanes in particular, there is a thread elsewhere for that, but more general applications like cars, ships, trains, dirigibles, etc. I was looking at the wikipedia page on the Toyota Prius (http://en.wikipedia.org/wiki/Prius) and noticed that the total power in KW is ~100, 100KW happens to be 2% of 5MW, and was wondering if Focus Fusion would scale down that far and what the radiation levels would be at that size. I’m thinking about Issac Asimov’s Foundation series and how they had nuclear reactors the size of a walnut and used nuclear power for everything (they had personal shields that where nuclear powered).

This is in my mind too. How small can we get? What are the physical limitations of boron+hydrogen fusion generator.

Can we put them in

a) Ships and submarines? Ships with basically unlimited cheap source of electricity is obviously the best place for those reactors. But how small ship?
b) Trains? Would there be enough space in locomotive for reactor?
c) Cars? Passenger cars are probably out of the question for quite a long time, but what about heavy-duty trucks? How small? Something like Liebherr T 282 B could probably fit one in.
d) Airplanes? Even if we put FF reactor inside, then what? Jets are faster than propeller powered planes. Would that even be suitable there?
e) Blimps? Unlimited range blimp could be useful for cargo transfer and maybe also as passenger sky-cruiser like ships.
f) Space? Satellites, space ships, Moon and Mars ships? Fusion reactor would be very good source for something like vasimr rocket, but how do we get that reactor in space?

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