news that makes you go HMMM

[paperburn1]

Has the government switched gears
http://www.the-weinberg-foundation.org/
looks like this puppy will fill the new shipboard role without fusion

[paperburn1]

The EAST experiments set a record for the duration of what is called an H-mode, or high-confinement plasma—the type that ITER and other tokamaks will employ. To achieve this duration, the EAST team beamed into the plasma what are known as "lower hybrid wave current drive" microwaves. The antenna-launched beams reshaped the magnetic field lines confining the plasma and suppressed instabilities at the edge of the gas near the interior walls of the tokamak. Controlling these fast-growing instabilities, called "edge localized modes" (ELMs), produced a record life span of more than 30 seconds for the H-mode plasma.

Read more at: http://phys.org/news/2013-12-technique- ... s.html#jCp

[D Tibbets]

First post refers to a fission reactor. I don't know what is in the pictured vessel, but I thoughtthat fission reactors were already faily energy dense- small for the output power. I would think gains would be mild at best. What is unclear is what has to be added to the system for operation. I'm guessing the steam plant is not included. As far as cooling, a water tank as backup is mentioned. The heat generated from fission products would seem to limit size as thermal loads are limiting factors, especially in emergency situations where coolent flow is challenged. Unless the fuel cycle is changed so that significantly less fission produced radioactive products are produced the cooling requirements are unchanged per unit of fission power produced.

Perhaps this design is designed for low power reactors. An approach that has been tried before but was abandoned due to safety concerns.


The second post references continueing efforts to control macro instabilities in Tokamaks. Apparently they have made gains, but 30 seconds confinement times seems poor compared to hundreds of seconds confinement times that I have heard of . Perhaps this refers to higher Beta conditions (H mode?) and thus higher densities and resultant higher fusion rates. This would maintain (or improve upon) triple product considerations. The mention of lithium added to the reactor to help minimize wall sourced contamination of the plasma is useful. Is the lithium added to the plasma, or coating the walls? If the latter, the use of lithium is not new to the Tokamak scheme. It has always been envisioned that it will be needed for tritium production. If it also helps reduce plasma contamination, it may be beneficial, but is not a new path for tokamak progress, though it might adjust some of the operating predictions .

Dan Tibbets.

[Teemu]

Not really.

The article only mentions DoE, who we know have never really been pro-polywell, DoD isn't even mention once. It doesn't list its application as ship power source, but rather the article list dozen other advantages of smaller modular design.

[paperburn1]

The smaller module reactors seem to be getting a lot of funding as of late. These companies have received hundreds of millions dollars funding.
Something that makes you go hmmm, and polywell funding. Nothing that I have heard of late.

The second article I was wondering if that could be used/ integrated into a polywell device.

[D Tibbets]

Controlling surface instabilities/ macro instabilities is essential in Tokamaks , but in the Polywell, such efforts are ideally not needed. All due to the shape of the confining magnetic fields. The claimed convex surfaces are not vulnerable to such instabilities.

Dan Tibbets

[paperburn1]

Thanks