Compared with tokamak devices, the biggest advantage of stellarators is the magnetic field confinement ability of plasma.
By rotating around the ring to stretch the poloidal cross-section of the flux surface and making the magnetic axis non-planar, the stellarator's magnetic confinement capability is more than an order of magnitude higher than that of a tokamak device.
But correspondingly, the manufacturing difficulty of stellarators is more than one level higher than that of tokamak devices.
All constraints on plasma turbulence imposed by the stellarator come from external field coils, which not only increases the constraint but also increases the engineering difficulty.
To put it simply, it is to reduce and solve problems such as plasma turbulent collision and magnetic surface tearing by improving engineering difficulty.
For controllable nuclear fusion technology, this grafting method is indeed one of the feasible methods, but now it has caused new troubles for Xu Chuan.
.......
In the office, Wang Jianzhang, the vice president of Western Superconductor, was sitting on the sofa, glancing at the door from time to time.
For the production of the external field coil of the stellarator this time, they were thinking of a solution as soon as they discovered it. However, due to various factors such as production level, materials, and time, it was really difficult to think of a solution.
After determining that Western Superconductor was not capable of solving this problem, he rushed over as the person in charge of the docking project to report.
Although from the contract point of view, the relationship between Xinghai Research Institute and Western Superconducting Group Corporation is only between Party A and Party B, the impact of Xinghai Research Institute's order and miniaturized controllable nuclear fusion technology is really too great.
"I don't know what to do this time."
In his mind, Wang Jianzhang thought about the subsequent impact. If the research on miniaturized controllable nuclear fusion technology is delayed due to their reasons, it will be difficult for the Western Superconducting Group to withstand this impact.
At this moment, the office door was pushed open.
The assistant who greeted him at first came in. Wang Jianzhang quickly stood up and was about to say hello, but the figure who walked in right after him stunned him.
"Mr. Wang, I heard that there are some problems in the production of outfield coils? Tell me what happened." Looking at Wang Jianzhang standing there, Xu Chuan said hello and asked.
Hearing the voice of inquiry, Wang Jianzhang suddenly came back to his senses and couldn't help but swallow, his heart trembling with nervousness.
This guy actually came here in person?
Then what happened this time might be really serious.
Thousands of thoughts went through his mind in an instant, but he quickly came back to his senses, took a deep breath, and explained: "That's it, Academician Xu."
"Regarding the batch of stellarator external field coils and magnet windings purchased by Xinghai Research Institute from our Western Superconducting Group, in terms of production, due to reasons such as immature materials and technology, the gap between good and defective products in the production line is very large, with more than
Thirty percent of the finished products failed to meet the standard requirements after preliminary testing."
"I have brought the relevant information and data, please take a look."
While talking, Wang Jianzhang quickly took out a piece of information in a document bag from the bag he carried with him and handed it over.
Xu Chuan nodded, reached out to take the information, opened it, and started to read it. While reading, he asked: "Is there no way to solve it?"
Wang Jianzhang said with a wry smile: "After discovering this problem, we immediately summoned the technical personnel and experts and professors in the factory to discuss it. At present, unless the entire production line is transformed, it will be difficult to find a solution in a short time.
solution to the problem.”
"Although we are already working on building a second advanced production line, water from afar cannot quench our thirst for nearness, so we can only make a report with you and the research institute first to see if we can come up with a solution together.
I hope Academician Xu Haihan."
Xu Chuan flipped through the documents in his hand, but he had no intention of blaming Western Superconducting Group.
After all, this is the first time for the production and manufacturing of improved superconducting materials.
On this basis, it is also necessary to complete the production of the external field coil of the stellarator, and the difficulty has increased by more than an order of magnitude.
Moreover, engineering problems are the focus of the stellarator production process.
After flipping through the documents in his hand, Xu Chuan began to think about it. The difficulty in producing stellarators lies in the extremely complex three-dimensional structure and the three-dimensional twisted coils that require extremely high precision, and the Western Superconducting Group produces the latter.
Judging from the document reports, there are two main reasons why more than 30% of the finished products fail to meet the standard requirements.
The first point is that the structure of the three-dimensional twisted coil is too complex, difficult to manufacture, and the equipment is not precise enough during processing, resulting in problems such as arc deviation and insufficient accuracy indicators after the parts are prepared.
This problem can be said to be serious or not serious.
There is no solution. Western Superconductor has also attached a solution to the document, which is to re-optimize the design and transformation of the original production line, or to add a new production line.
However, both methods require a long time to adjust.
The impact of the second problem is relatively greater than the first one.
The material used for the external field coil of the stellarator is an improved superconductor. It is made of a high-temperature copper-carbon-silver composite superconducting material by doping Cu atoms in excess Cu nanoparticles into the holes to create a magnetic trap that improves the resistance.
Magnetic effect.
In a quasi-two-dimensional plane structure, both Xinghai Research Institute and Western Superconducting Group can improve the topology of the superconductor surface through a series of means.
But when it is placed on the external field coil of the stellarator, the original quasi-two-dimensional planar coil structure becomes a twisted three-dimensional coil, and the surface is connected with various uneven layers of protrusions and depressions.
The change in shape is simply like the original regular donut, but now it has become a twist sprinkled with sesame seeds and chopped peanuts.
There is no doubt that it is more than an order of magnitude more difficult to enhance topological holes on the surface of the latter than the former.
This chapter is not finished yet, please click on the next page to continue reading the exciting content! And this problem cannot be solved by increasing the production line or optimizing the production line.
Unless the Western Superconducting Group finds a new way to industrialize the production of improved superconductors and solve this problem. Otherwise, no matter how the production line is optimized with the current methods, this problem will still exist.
Of course, adding production lines to expand production scale is definitely effective, but judging from the data in the documents, Xu Chuan is certain that this defect will be even more magnified in subsequent miniaturized parts.
Due to its volume, the now-extended Huaxing stellarator coil can be enhanced by some means when topological acupuncture doping is performed. However, the smaller the volume, the weaker the effect of the enhancement means will be.
If the size of the external field coil is further reduced, I am afraid that the number of qualified products will be further reduced.
Although this problem can also be solved by adding production lines, when the defective rate is too large, the price paid is a bit too high.
.........
After thinking for a while, Xu Chuan put the document in his hand on the desk, raised his head and said, "I already understand the problem. It is indeed a difficult problem."
Looking at Wang Jianzhang, who was standing nervously opposite, he smiled and comforted: "Don't worry, I don't mean to blame you. It doesn't mean that you can definitely control this kind of problem. The most important thing now is to find a solution.
solve these problems."
After hearing these words, Wang Jianzhang breathed a sigh of relief. Even though the man in front of him was only a year or two older than his son, standing in front of him was really stressful.
Nodding, he quickly replied: "What Academician Xu said is that this problem has honestly exceeded the research and development capabilities of the Western Superconducting Group. In addition to adding production lines in a short period of time, we may not be able to think of anything else."
Good idea."
Xu Chuan thought for a moment and said, "Let's do this. Send me the detailed production information and technical data, and I'll take a look at it first."
"No problem, I will prepare the information when I get back here, but..." After a pause, Wang Jianzhang glanced at Xu Chuan cautiously, and then said: "Will this be too troublesome for you, Academician Xu?"
, after all, your time is so precious.”
Xu Chuan waved his hand and said: "You just need to send the information. I will communicate with the Chuanhai Research Institute later, and then arrange for two people to go to your factory to study together. First, we will discuss the problem.
solve."
...
The production of the external field coil of the stellarator encountered a problem. Even though this problem did not strictly belong to Xu Chuan, he still had to find a way to solve it.
Otherwise, superconducting coils made of improved superconductor materials are the core of miniaturized controllable nuclear fusion technology.
Regarding this problem, Xu Chuan could not allow time to drag on like this, and apart from him, it could only be said that it would be more difficult for others to solve this problem.
After all, he personally developed the improved superconductor material, and no one knows the properties of this material better than him.
After obtaining relevant production materials and data from Western Superconducting Group, Xu Chuan began to think about solutions to the problem.
In order to seek inspiration for solving the problem, he collected a large number of papers related to materials, superconducting materials, doping technology, topological space equality and other fields, trying to get inspiration from some public research materials.
But after two consecutive days, he still made no progress on how to improve materials or production methods.
After reading a paper in the field of materials, Xu Chuan leaned on the back of a chair in his office, stared at the ceiling, shook his head, and breathed a long sigh of relief.
To be honest, no one can answer this question, and there is even no previous research that can be used as a reference.
Improved superconducting materials have only appeared not long ago, and the outside world cannot even find relevant papers.
As for the paper that provides the theoretical basis for improved superconductors, let alone a cutting-edge field that not many people are studying, he has not even published the paper.
In this case, there is little hope of finding reference ideas from those public papers.
"Professor, you have a big class on mathematics and physics this afternoon. This is your class schedule and time."
In the office, a voice interrupted Xu Chuan's thoughts. He turned around and saw that assistant Tang Ran was putting a course schedule on the table.
Xu Chuan breathed a long sigh of relief, nodded, and asked: "What time is it in the afternoon?"
Mathematical physics was a course he started in the second half of last year. After the mathematics department of NTU was expanded into a college, he agreed to President Tan Shaoyuan’s request and opened a mathematical physics course, which mainly talked about how to apply mathematics to other physics.
Of course, sometimes he will also incorporate some other methods, such as how to use mathematics to calculate data in materials, chemistry, biology and other experimental processes, etc.
Therefore, this course is quite popular. Not only students from the Department of Mathematics attend it, but also students from other colleges occasionally come to observe.
"At three o'clock, in Lecture Room No. 1 of Teaching Building No. 3, do you need me to help you prepare any materials?" Tang Ran quickly replied.
"No, there's nothing to prepare." After saying that, Xu Chuan stood up from the office chair, moved his body and said, "I'm going for a walk. If you need anything, just call me."
"Um."
Tang Ran nodded in response, looking at Xu Chuan's leaving figure, she shook her head slightly.
She had watched Xu Chuan's performance when he was studying problems in the office these two days. Maybe he encountered some difficulties? Anyway, he was not in a good mood these two days, and he didn't want to talk to anyone.
But there was nothing she could do.
After all, the professor was researching something that she couldn't help with at all. Let alone helping, she probably wouldn't even understand the question.
For her, the only thing she could do was to pray in her heart, hoping that the professor could find a solution as soon as possible.