3 ms·
If I understand what you're suggesting I think it addresses only the aspect of how to convert the energy released by fusion reactions into useful work (ie. mech
by tgflynn 15y ago
If I understand what you're suggesting I think it addresses only the aspect of how to convert the energy released by fusion reactions into useful work (ie. mechanical or electrical energy). This is not actually the difficult part of building a practical fusion reactor.
Even if your design could work you need a way to produce pure fusion explosions. There is currently no sufficiently energy efficient way of doing this. Thermonuclear bombs require a fission explosion to trigger them (in fact I believe most produce more energy from fission than from fusion).
The laser based inertial confinement schemes actually are designed to produce tiny pure fusion explosions. If such a system could be built that produced more fusion energy than the driving lasers consume there would be many ways to convert that energy into electrical energy (photovoltaics, steam generators/turbines, etc.). I suspect an internal combustion engine would not be the most practical of these methods from an engineering point of view.
- tocomment 15y ago> (in fact I believe most produce more energy from fission than from fusion). If this is true, then that puts a kink in my design. I assumed the vast majority of energy output was from fusion. (why else would they build them?) I mainly suggest my design because it seems so difficult to trigger fusion without fission using current technology.
- tgflynn 15y agoI mainly suggest my design because it seems so difficult to trigger fusion without fission using current technology. How does your design address that ? Are you saying the fusion reactions would be triggered by the mechanical compression of the pistons in the cylinder ?
- tocomment 15y agoI don't seem to be allowed to reply to the comment below: > How does your design address that ? Are you saying the fusion reactions would be triggered by the mechanical compression of the pistons in the cylinder ? I'm saying fusion reactions are triggered by the detonation of a hydrogen bomb (fission triggers fusion inside the bomb).
- tgflynn 15y agoOK, so then what you're proposing isn't a pure fusion reactor but a hybrid fusion-fission reactor. That's probably going to combine many of the disadvantages of fusion and fission. You get both the highly radioactive and long-life decay products of fission, still need relatively rare fissile fuel and you get the containment problems of fusion. Moreover if you need a fission explosion trigger you need a critical mass of fissile material for each detonation so there's a limit to how far you can scale down the process. I think it's highly unlikely this could be practical.
- tgflynn 15y agoJust to be clear, now that I have a better understanding of your proposal, I didn't mean that a device in which the majority of the energy comes from fusion isn't feasible, just not typical. Quantitatively I don't know how large you can make the fusion/fission energy ratio but there will always be some fission with the radioactive decay product problems inherent to that.
- tocomment 15y agoSo maybe it would work? You just need a way to handle the radioactive waste, and a way to engineer on a very large scale.