The top student must be diligent.

Chapter 217 Tokamak, Big Problems

At the gate of the Plasma Institute, Li Jiangan, Zhao Zhanyou and other leaders of the institute were standing there, welcoming a young man who had just got out of a car.

As for this young man, it was naturally Xiao Yi.

"Professor Xiao, welcome back again!"

Li Jiangan walked up and shook hands with Xiao Yi.

"Hello, Academician Li."

Xiao Yi also nodded to him, and then saw Zhao Zhanyou next to him and called out, "Director Zhao."

Zhao Zhanyou smiled at Xiao Yi.

This time, Xiao Yi came to the Institute of Plasma Physics at their invitation. As for the reason, it was naturally because of his paper.

"Professor Xiao, I have read your paper. I really don't know how to describe the multi-fluid NS equation model you developed in that paper."

After Li Jiangan greeted everyone, he began to praise Xiao Yi's paper.

"That model can not only help us analyze the Greenwald limit, but also help us study various issues such as the internal structure of the tokamak device. I think with your ability, you are more than qualified to be a researcher in our plasma research institute."

Zhao Zhanyou next to him also nodded repeatedly and said, "Yes! Professor Xiao, you probably can't imagine how excited our Academician Li was after we read your paper that day. He kept saying that you are the dawn of the future of nuclear fusion in China, and that if China can achieve nuclear fusion within 50 years, it must be you."

Li Jiangan, who was standing next to him, glared at Zhao Zhanyou and said, "Don't talk nonsense here. Just talk about it in private. If you speak out now, won't you put pressure on Professor Xiao?"

Then he said to Xiao Yi apologetically: "I'm sorry, Professor Xiao, this person has always been like this, a little frivolous, don't take it to heart."

"Of course, I do think that if you can study nuclear fusion, you might be able to make a huge breakthrough in this field."

"Just because you can come up with such a model to solve the Greenwald limit, I think you should be the one to solve nuclear fusion!"

Xiao Yi looked at Academician Li's sincere expression with a look of helplessness and amusement.

These two people sang a duet...

Isn't it a bit too easy to be discovered?

Last time you wanted to invite him to collaborate on building a new tokamak device. This time you invited him in the hope that he could join in the research on nuclear fusion?
Ok……

He laughed and said, "Haha, thank you Academician Li for your trust. Of course, controlled nuclear fusion is indeed a difficult topic. If you really want to put your heart and soul into it, it will take a lot of time. I personally prefer to do it step by step."

Hearing Xiao Yi say this, Li Jiangan could only helplessly say: "What you said does make sense. Such a problem really cannot be solved overnight."

Xiao Yi smiled and said, "Okay, you two, didn't you invite me here today to verify Greenwald's limit?"

Li Jiangan came back to his senses and then laughed, "Oh, right, right, I almost forgot about the main thing."

"Then let's go to the research institute now."

Then they stopped talking and entered the research institute.

……

The main purpose of Xiao Yi's coming here today is to discuss how to verify the new Greenwald limit proposed in Xiao Yi's paper.

In physics, theories are just theories. Whether they can be implemented in the end still depends on experimental results.

As for how to verify it through experiments, it requires igniting the fusion reactor.

"It just so happens that we originally planned to conduct an ignition experiment before the Chinese New Year, which is only ten days away. Now that we have your paper results, we can also do a verification and publish an article in a top journal."

When they arrived at the office, Li Jiangan said to Xiao Yi, and at the same time took out a piece of information and handed it to Xiao Yi.

Xiao Yi took the information and took a look at it.

This document describes the plan to verify the New Greenwald Limit.

The solution is actually quite simple, it is nothing more than controlling the internal plasma density.

The first is parameter selection. Based on the simulation results, the appropriate plasma current and small radius are selected to achieve the new Greenwald limit density.

The current tentative plasma current is 1MA, and the minimum radius is 0.45 meters, which is also based on the design parameters of the Eastern Super Ring.

When it comes to ignition, the plasma discharge is carried out according to the set parameters, and the plasma density is gradually increased until the new Greenwald limit density is reached.

"That is to say, under this parameter, the density of the plasma in the Vostok Super Ring must reach 2.12×10^20/m^3, which is equivalent to reaching the new Greenwald limit."

Xiao Yi made a simple calculation in his mind and came to this result.

"Yes." Li Jiangan nodded, but then he also smiled and said: "Of course, in fact, as long as it can exceed 1.57, it will be fine. After all, every part beyond that is a new limit."

Xiao Yi also smiled.

The original Greenwald limit on the EAST is approximately 1.57×10^20/m^3.

而现在提高了35%后，也就是2.12×10^20/m^3。

Therefore, as long as it can exceed 1.57, it is indeed a new limit.

He said: "Then I look forward to the day of lighting the fire."

"Well, I'll definitely invite you to visit when the time comes." Li Jiangan said, "By the way, I'll let you experience what it's like to press the ignition button."

"Oh?" Xiao Yi became interested: "It does sound interesting. Is it like the ignition of a rocket?"

Li Jiangan smiled and said, "That's not the case. When they ignite a rocket, they really ignite it. When we ignite it, we just pass an electric current through it. After a few tens of seconds, the temperature of the plasma in the cavity reaches 100 million degrees. Well... the temperature is much higher than that of a rocket, but it doesn't look as fierce as a rocket."

"Otherwise, when the rocket is ignited, it can attract so many people to watch. But when our nuclear fusion ignition is ignited, only we can watch it here."

Xiao Yi laughed and said, "If you announce the ignition time, maybe it will attract a lot of people to come and watch."

"Forget it then."

Li Jiangan shook his head. "We can't accommodate so many people here. Besides, once they heard that nuclear fusion might cause radiation hazards, they would have run away a long way."

"That's true."

Xiao Yi shrugged.

Nuclear fusion will of course produce radiation. The neutrons generated during the deuterium-tritium fusion reaction are a highly harmful source of radiation.

However, the Tokamak device is usually surrounded by a neutron shielding layer, so there is basically no need to worry about nuclear radiation.

Of course, they know from a scientific point of view that these radiations will not harm the human body, but for other ordinary people, they will of course run as far away as possible.

It’s like there was a place where a nuclear power plant was going to be built, but when the residents around learned about it, they all expressed their opposition, and ultimately the nuclear power plant could not be built.

However, from the perspective of the public, this kind of thing is normal. After all, not many people are willing to live next to a nuclear power plant. Even if it is really safe, they will still feel a little uncomfortable.

"Professor Xiao." At this time, a voice came from the door, and Zhao Zhanyou walked in with a pile of files in his hands.

"This is what you want, the overall structural information of our Eastern Super Ring."

Zhao Zhanyou put the files on the table, patted them, and said to Xiao Yi, "This is the confidential document of our Institute of Plasma Physics! If nothing else, just find a reliable company. As long as they have this information, they can rebuild an Oriental Super Ring."

Xiao Yi's eyes lit up. He came here today for another purpose, which was to get the detailed structural information about the Oriental Super Ring.

With this information, he will be able to activate his [Perfect Engineering] ability to study the Tokamak device more closely.

Without further ado, he quickly walked forward, took down the first file, and pulled out stacks of information from it.

These materials contain detailed descriptions of the structural design of each part of the EAST, as well as various engineering drawings, etc., down to the smallest detail, down to a single screw.

It is exactly as Zhao Zhan had lobbied. If a construction company comes and builds according to this plan, they can build another Oriental Super Ring.

"Thank you."

Xiao Yi said.

Zhao Zhanyou waved his hand and said, "You're welcome. Although that's true, this thing did have some value back then, but now so many years have passed, these design drawings are nothing. Even if they are made public, I don't think any research institute will really build it according to this."

"Just take it back to the Science Island laboratory and take a look. Then bring it back when you're done. Just don't lose it."

Xiao Yi nodded, but his eyes were still fixed on the contents of the document.

In the eyes of Zhao Zhanyou and others, this thing has no value anymore, but in his eyes it is of infinite value.

"Then I won't bother you guys here. I'll take this information back and study it carefully." Xiao Yi said, "I'll come back when the ignition is officially started."

"Okay." Zhao Zhanyou nodded.

……

Soon, Xiao Yi packed up the information and took it away.

Looking at the car going away, Zhao Zhanyou said in confusion at the gate of the Plasma Institute: "By the way, why does Xiao Yi want that information?"

Li Jiangan smiled and said, "Maybe he can come up with a new tokamak device in the future?"

Zhao Zhanyou shook his head: "The structure of the Tokamak has basically been finalized. Even if we optimize it, it won't be able to be optimized any further, right?"

"Who knows?" Li Jiangan spread his hands and said, "As for structure, you can never imagine how it can change. Just like from a topological point of view, a person is also a donut."

Zhao Zhanyou pinched his head, shook his head and said, "Forget it, I'd better not think about this. I didn't even learn geometry very well back then, let alone topology."

Li Jiangan smiled, then turned around and walked back into the research institute.

"Okay, if you don't want to think about it, then forget it. Let's go back. We still have to prepare for the ignition."

"What's more, inviting Xiao Yi here today can be regarded as a preliminary achievement of our goal."

“He did become interested in nuclear fusion.”

……

Time passed quietly.

After Xiao Yi returned to the Science Island Laboratory with the pile of information, he devoted all his time to the structural research of the Oriental Super Ring.

Based on the information above, he slowly outlined every detail in the perfect project.

It took about 4 days for him to finish reading all the information and completely construct an Oriental Super Ring in his mind.

“Finally figured it out.”

In the office, Xiao Yi closed his eyes and carefully observed the complex structure in his mind.
It is important to know that the complexity of the tokamak device ranks among the highest among all scientific instruments and is the pinnacle of modern scientific instruments.

It is obviously difficult for one person to fully understand such a structure.

But fortunately, there is absolutely no problem for a cheater.

Through the effects of perfect engineering, Xiao Yi can fully grasp every detail of the Oriental Super Ring in his mind and control it.

"Well... let's not worry about the first wall material and other things for now. The most important thing is the control of the plasma flow."

Xiao Yi began to control the changes in the overall structure, the most important of which was the magnetic field.

Thinking of this, he also began to control the changes in the magnetic field in his mind.

However, due to the limitations of the tokamak structure, no matter how he optimizes it, he will face a very important problem.

“How can we harness fusion energy?”

Xiao Yi frowned.

As the most successful fusion device today, the tokamak device's greatest advantage lies in its ability to confine and control high-temperature plasma. It can precisely control high-temperature plasma in a circular cavity. No matter how high the temperature or how fast the speed of the plasma is, it is still controlled by the magnetic field.

However, its advantage lies only in the constraints.

It can only be restrained but not utilized, just like lighting a fire to keep warm, but in order to prevent the fire from going out, covering it completely so that the heat inside cannot escape.

Obviously, this is stupid.

As a result, even boiling water cannot be done properly.

Xiao Yi touched his chin, frowned and began to think.

There is currently something called a tritium breeder blanket, in which the lithium can react with high-energy neutrons to produce tritium, which provides fuel for nuclear fusion and absorbs heat, which can then be transferred to the outside to generate so-called water-boiling electricity.

But there is obviously a problem. When these tritium breeding blankets react with high-energy neutrons, they will inevitably be worn out and gradually lose their effectiveness. At this time, we have to consider how to take out these breeding blankets and replace them with new ones when fusion occurs. We can't stop the operation of the reactor as soon as they are damaged.

In addition, the most important energy for nuclear fusion lies not only in these high-energy neutrons, but also in the plasma.

How to use these high-temperature plasmas?

The exchange of heat still requires direct contact. We cannot rely solely on the energy brought by thermal radiation for exchange. Direct contact will cause losses.

As for the magnetohydrodynamic generator, although it is also a good idea, it still faces a key problem: how to control the high-temperature plasma passing through the magnetohydrodynamic generator?
As various questions lingered in his mind, Xiao Yi's brows became more and more furrowed.

As he ran more simulations in his mind.

Eventually, he came to a conclusion.

"Tokamak...is a huge problem."

(End of this chapter)