MSNW ready for breakeven experiment

[Ivy Matt]

It appears John Slough’s team at the University of Washington will begin a breakeven experiment this summer. Their presentation at the 2012 NASA Innovative Advanced Concepts Spring Symposium, which can be found here, has some information about their experiment. They expect to be able to achieve a fusion gain of about 1.6, presumably using deuterium and tritium as fuel.

[dennisp]

Would this be practical for a power plant?

And would it have potential for a launch rocket (by adding reaction mass), or just for deep space propulsion?

[zapkitty]

The forum ate my response… give me a few minutes to reconstruct…

… damn, it should react better to intervening posts. Rezwan, is that a setting you can change in expression engine?

[ikanreed]

So, 2013 will be the year of fusion. It sounds like a whole bunch of major projects are set to make breakthroughs.

[zapkitty]

MSNW seems to have shifted things a bit. That’s not exactly what Helion used to be. Helion used colliding FRCs with the resultant FRC clamped by superconducting coils for the final push.

This is a compromise… a blend of the Helion concept with the MSNW space drive concept. The space drive collapses multiple foil Al liners on an FRC for that final push and thus introduces all the consequent issues of replacement and alignment of precision-machined disposable metal parts for each individual shot.

… shouldn’t be a showstopper but not the best outcome for a power plant

Is this an intermediate step to the proposed Helion design? Do they still regard a Helion sans metal drivers as an achievable goal?

It does bring to mind the rumors that Tri-Alpha has had to scale back from aneutronic to neutronic fusion.

Of course any credible claim at breakeven would start breaking up the interest/funding logjam.

… and I do note that in the pdf linked MSNW takes a deliberate swipe at boron fusion by listing it as not “based on currently accepted principles of physics and reasonable technology extrapolation” alongside cold fusion, matter-antimatter and wormholes.

Oh?

Perhaps the published successes of LPPX since then will be treading closely upon a few heels right about now… 🙂

[Tulse]

zapkitty wrote: MSNW takes a deliberate swipe at boron fusion by listing it as not “based on currently accepted principles of physics and reasonable technology extrapolation” alongside cold fusion, matter-antimatter and wormholes.

Perhaps the published successes of LPPX since then will be treading closely upon a few heels right about now… 🙂

To be perhaps excessively fair, LPPX hasn’t done any pB11 shots yet…

[zapkitty]

Tulse wrote:
To be perhaps excessively fair, LPPX hasn’t done any pB11 shots yet…

Oh, quite true. But there could be said to be more than a smidgen of difference between an experimental program that is making measurable progress (LPPX) and space drive concepts such as cold fusion, matter-antimatter and wormholes.

By its very nature an FF unit is a space drive waiting to happen 🙂

[Ivy Matt]

In fact, one of the other presentations, by Tarditi, Miley, and Scott, reminded me of the DPF. It’s titled “Aneutronic Fusion Spacecraft Architecture”, and advocates a fusion thruster design that uses the fusion products directly for the production of thrust. With such a design, the efficient production of electricity (and therefore net energy gain) is unnecessary. For this application, the main thing you need is a beam of fusion products. Of course, the concept favored by Tarditi, Miley, and Scott uses an inertial electrostatic confinement device in “jet mode”, but it occurred to me that a DPF could be used for the same purpose. Note that the presentation uses the phrase “direct conversion” in the sense of converting fusion energy directly to thrust, rather than to electricity.

[ikanreed]

You know what really scares me about fusion thrusters? You have limited resources to restart them once you end the reaction. Low earth orbit is not a place to which I’d like to take a one way trip.

[zapkitty]

Ivy Matt wrote: In fact, one of the other presentations, by Tarditi, Miley, and Scott, reminded me of the DPF. It’s titled “Aneutronic Fusion Spacecraft Architecture”, and advocates a fusion thruster design that uses the fusion products directly for the production of thrust.

Did you know that NASA’s JPL was funding Lerner-hakase’s DPF work for exactly that purpose — a high-energy, high efficiency space drive — until the Halliburton administration banned NASA from any and all fusion research after 2001?

[zapkitty]

ikanreed wrote: You know what really scares me about fusion thrusters?

Kzinti?

ikanreed wrote: You have limited resources to restart them once you end the reaction.

As almost all current fusion contenders which are also drive candidates are pulsed concepts that seems to be a non-issue 😉

(Polywell could be an exception)

More seriously, you’re thinking in early NASA’ish terms of all-or-nothing mission parameters. Even the STS did a little better than that.

ikanreed wrote: Low earth orbit is not a place to which I’d like to take a one way trip.

Non-sequitur. LEO is almost certainly where early fusion-powered spacecraft will [em]start[/em] their journeys.

If you’re in LEO and can’t restart your drive and if for some strange reason you don’t have basics like an engineering crew w/ toolboxes aboard then you use maneuvering thrusters to waddle back to the station and make repairs. If the thrusters are also out then you ask station ops to send out a tug to haul you back to the station.

If it’s an emergency and you have to evacuate immediately then you get in your Dragon, Soyuz or Orion lifeboat and return directly to Earth…

And yes, on Titan orbit would be another matter.

That’s why that ships that go out that far will have actual engineering spaces with actual engineers and those engineers will have actual toolboxes…

… somebody could photoshop an EMU into a photo of LPPX and label it “Derek in LEO…”

[ikanreed]

Well, I suppose that’s pretty reasonable. But, for example FoFu-1 is very sensitive to disruption. Imagine if you had tin whiskers on the electrodes, even very tiny ones.

[Ivy Matt]

zapkitty wrote: Did you know that NASA’s JPL was funding Lerner-hakase’s DPF work for exactly that purpose — a high-energy, high efficiency space drive — until the Halliburton administration banned NASA from any and all fusion research after 2001?

Well, I was aware that the JPL had previously funded Lerner’s work. I’ve been trying to find if that work fell under the NASA Institute for Advanced Concepts, because if they completed a Phase I study under that program, they would now be eligible to submit a Phase II proposal under the new NASA Innovative Advanced Concepts program, but I haven’t found Lerner on the list of studies funded by the first NIAC.

[zapkitty]

ikanreed wrote: Well, I suppose that’s pretty reasonable. But, for example FoFu-1 is very sensitive to disruption. Imagine if you had tin whiskers on the electrodes, even very tiny ones.

Tin? Where would the tin come from? The electronics would have to be outside the vacuum chamber.

And even an FF space drive will have a vacuum chamber… as the fuel pressure has to rise to several torr before you can start it.

That it is space-based would just mean that you save on the cost and maintenance of a vacuum pump.

A plasma window should be able to allow the beam to exit the chamber into an exhaust assembly of some kind while maintaining chamber pressure.

[zapkitty]

Ivy Matt wrote: Well, I was aware that the JPL had previously funded Lerner’s work. I’ve been trying to find if that work fell under the NASA Institute for Advanced Concepts, because if they completed a Phase I study under that program, they would now be eligible to submit a Phase II proposal under the new NASA Innovative Advanced Concepts program, but I haven’t found Lerner on the list of studies funded by the first NIAC.

That would be cool! And a bit ironic 🙂

[Author]

Posts