Chapter 764

Just as Xu Qingzhou was diving into the liquid metal divertor improvement plan, on August 27, the Max Planck Institute for Plasma Physics in Germany released explosive news.

The W7-X stellarator's Lawson criterion threshold maintenance time successfully reached 360 seconds.

This meant that the W7-X stellarator surpassed the US NIF and became the most likely controlled nuclear fusion device to achieve commercialization at present.

For the fusion field, achieving commercialization requires meeting two independent indicators—Q value and Lawson criterion.

Xu Qingzhou and the others' current route is to first achieve the Lawson criterion, proving that the fusion reaction can be self-sustaining, and then make a breakthrough in the Q value to complete net gain.

The W7-X stellarator is the opposite; last October, its Q value reached 15, and the operating time was 30 minutes.

Why is it that the Q value has reached 15, far exceeding the standard for a tokamak to build a demonstration reactor, yet it still can't build a reactor?

This is because the plasma density of W7-X has not met the standard.

The Lawson criterion requires density ≥ 10 particles/m, but because of the magnetic field structure limitation, the stellarator usually controls the density at a lower level to maintain plasma stability.

To put it simply, it's like a rocket engine reaching the ignition temperature, the combustion chamber is large enough, and it can continuously spray to generate thrust for 30 minutes, but the fuel injection concentration is insufficient, and the thrust cannot break through the threshold, which leads to no real effect on the rocket's takeoff.

Now, it has reached the Lawson criterion and maintained it for 6 minutes.

That is to say, besides being able to continuously generate thrust for 30 minutes, this engine can now push the rocket to fly at high altitude for 6 minutes.

Although it will still crash after 6 minutes, going from unable to take off to taking off is already a qualitative leap.

Next, as long as the maintenance of the Lawson criterion and Q value is constantly extended, building a demonstration reactor is just a matter of time, and in terms of progress, it is considered to have directly pulled a lead over the US.

"Expected."

Xu Qingzhou was not very surprised by the achievements made by Klinger and others.

In terms of time, Germany got the superconducting film and upgraded the superconducting magnet about 1 year faster than the US. For now, even half a year can pull a certain gap.

"The commercialization of the stellarator seems to be much faster than the tokamak."

"No wonder Klinger said in the email not to be too surprised."

Xu Qingzhou leaned on the chair, squinting at the window, and laughed softly. "No matter which aspect you look at, this is indeed an unprecedented progress, but Qiankun No. 1 is not bad either."

"If everything goes well, the next experiment can be started in mid-October."

He had considerable confidence in the device he designed.

Putting aside distractions, Xu Qingzhou set his sights on the design data of the current traditional tokamak.

Academician Ren Nan's magnetohydrodynamic (MHD) diversion technology verification is going very smoothly, and now TBR ≥ 1.03, only 0.6 away from solving the tritium self-sufficiency problem.

The divertor modification has a clue, and he plans to focus on the two problems of "insufficient toroidal field strength" and "low neutral beam injection efficiency" of the spherical tokamak.

While completing the net energy gain experiment, there must be a demonstration reactor design plan that can be brought out.

At 5:00 PM, Xu Qingzhou went to the laboratory again.

"There is still a 0.2% gap from the estimate... Do a few more rounds of experiments to see where the problem is."

In the laboratory, Xu Qingzhou said to team leader Hu Jingxuan.

Hu Jingxuan's team is responsible for magnetohydrodynamic vortex impurity capture to continue to increase the heat load bearing limit of the first wall.

"Okay."

Hu Jingxuan answered crisply.

Xu Qingzhou took the data and went to Senior Sister Ren Xiaoling's side. During this period, Ren Xiaoling basically guarded the laboratory, while he did data analysis and the design of the tokamak demonstration reactor.

Hu Jingxuan said to the 3 team members: "Okay, everyone go eat first, gather at 6:30, and we will study how to improve the magnetohydrodynamic protection mentioned by Professor Xu."

"Okay."

Everyone packed their things, ready to eat first, and at the same time, they started chatting.