Material Empire

Xia Yangjie didn't know why he was going crazy, he had been sitting on the bench for four years, yet he was still so impulsive. Just now, I heard some teachers who had just returned from a meeting discuss a few words in the teaching and research room, and Xia Yangjie chased him out with his notebook in his arms.

Xia Yangjie graduated from a prestigious university in China four years ago and was assigned to teach in the Chemical Engineering Department of Pujiao University. Originally, he did not study polymer chemical engineering, but mathematics. The reason why he came to the Department of Chemical Engineering is ridiculous to say. It was because the female teacher who taught mathematics in the Department of Chemical Engineering gave birth to a child and was unable to attend classes for two months. To meet her lack, Xia Yangjie, who had just graduated, was assigned here.

Xia Yangjie was not a nerd, but he really lacked talent in lecturing. In his opinion, jumping from one formula to another is a simple matter, and there is no need to list the detailed derivation process at all. But when he used this way of thinking to give lectures, a large number of his students failed their subjects.

The head of the department talked to him several times, and went to the classroom to listen to his lectures in person, and finally decided that this person was not a material for teaching mathematics at all. Fortunately, the female teacher who gave birth had returned from maternity leave at this time, and Xia Yangjie was honorably laid off with deep regret and bewilderment.

Of course, the Department of Chemical Engineering cannot keep an idler in vain. After research, Xia Yangjie was transferred from the teaching and research section of public courses to the teaching and research section of polymer, and undertook the research work on the filament winding model.

Filament winding is a kind of composite material production technology that appeared in the 1940s. Simply put, it is to wind the fibers soaked in resin on a mandrel round by round according to certain rules. After the resin is dry, take off the mandrel, and then A fiber resin product can be obtained.

The principle of fiber resin is a bit like the reinforced concrete we usually see. The resin is equivalent to cement, and the fibers in it are equivalent to steel bars, which can improve the strength of the material. The most common fiber resin is FRP, which is a plastic reinforced with glass fibers.

In addition to glass fibers, fibers used in filament winding products also include aramid fibers, carbon fibers, and the like. Filament winding technology can be used to manufacture pipes, pressure vessels, solid rocket motor casings, etc. It is a new material technology in the ascendant.

As early as the end of the 1950s, my country began to conduct research on filament winding technology. At that time, it mainly served the cutting-edge national defense technology needs of two bombs and one satellite. In the 1970s and 1980s, my country successively imported several sets of fiber winding equipment from West Germany, Italy, Japan, the United States and other countries, and has carried out related work on localization.

The method of fiber winding is a bit like the process of winding cotton yarn into spindles in a cotton spinning factory. The mandrel to be wound rotates at a certain speed, and the fibers move back and forth along the axial direction, thus forming a winding line round by round. Xia Yangjie's task in the polymer teaching and research section is to help the teachers who are doing research in this area to calculate the running speed of the mandrel and the speed of the fiber spinning nozzle to ensure that the wound structure meets the design requirements.

The teachers in the polymer teaching and research section are all from chemistry background, and the foundation in mathematics is not good, so there are some obstacles in the calculation of such a model. But for Xia Yangjie, who is quite talented in mathematics, this model is as simple as a few exercises in differential geometry, and he solved these problems that have troubled everyone for a long time. No one expected that it was these few exercises that made Xia Yangjie fascinated by this field, and it was out of control.

Filament winding density, angle, fiber overlapping method, etc. all have a significant impact on the performance of filament winding products. The mechanism of this effect is not so much a chemical problem as a very fascinating mathematical problem. In addition, the traditional filament winding products are mainly convex and symmetrical gyratory. For asymmetrical products, or so-called double-concave gyratory, how to realize the winding process is also a subject that requires a lot of space calculations. All these subjects made Xia Yangjie feel infinitely interesting.

After completing the task assigned by the teaching and research section, Xia Yangjie started his own research. He introduced a large number of mathematical concepts into polymer research, and proposed a multi-degree-of-freedom fiber winding and laying model, as well as gradient projection methods based on the Jacobian matrix, weighted least squares methods based on SVD decomposition, and inverse kinematics. I had a great time learning the closed-loop solution method and so on.

In any field, a person who is one step ahead is a genius, and a person who is more than ten steps ahead is a lunatic. Xia Yangjie's research on the theory of filament winding is not only more than ten steps ahead of his colleagues, but the result is that few people care about it.

In the entire polymer teaching and research section, no one knew what Xia Yangjie was doing. The differential geometry calculations he wrote, no one could understand them except himself, and they didn't know what the thing was doing. Xia Yangjie couldn't find a colleague in the teaching and research room who could discuss the issue with him, so he wrote an article and submitted it for submission, and the editors in the editorial department didn't know whether what he wrote was right or not. In four years, he didn't even publish a paper. So in the eyes of the department leaders and colleagues, he became a waste who was ignorant and only used some mathematical formulas to put on airs.

This time Qin Hai and Lu Xiaolin came to the Department of Chemical Engineering to hold a seminar, and the secretary of the academic affairs also notified Xia Yangjie to attend the seminar, but Xia Yangjie was already chilled by this kind of meeting. He didn't think bureaucrats from government departments could understand his theory. Besides, he himself is not very popular, so why bother to join in the fun? So, during the meeting, he stayed in the teaching and research room by himself, deducing the formulas that only he himself understood.

The teachers in the teaching and research section were ridiculed by Qin Hai at the meeting, and all of them were ashamed and speechless. After returning to the teaching and research room, everyone talked about the setbacks they suffered today. Apart from being aggrieved, some people felt that Qin Hai's knowledge was indeed extraordinary, and some of the research directions he proposed were really inspiring to him.

During this period, a teacher who had a decent relationship with Xia Yangjie on weekdays knocked on Xia Yangjie's desk and said to him casually, Xiao Xia, it's a pity that you didn't go today. That young man was given to the town.

What do you mean? Xia Yangjie pushed the myopia glasses on his nose and asked in puzzlement.

Today, a very young young man came to the localization office and demoted all of us. I thought, we can't understand the things you usually do. If you tell that young man, maybe we can. Make him ignorant, at least we won't be wiped out. The teacher said half-jokingly.

In fact, what he thought was another matter in his heart, he hoped that Xia Yangjie could also attend this meeting and be demoted by Qin Hai, so that his mind would be balanced. The ancients said it well, good things should be enjoyed by oneself alone, and when bad luck should be pulled along with others, this teacher has always admired such ancient teachings.

Xia Yangjie didn't think too much, he just asked strangely: What kind of young man can demote our entire teaching and research section, what did he say?

The teacher introduced some important content to Xia Yangjie, and then said: By the way, Xiao Xia, aren't you doing some kind of fiber winding? I see that among the topics they listed, there is also a problem of free-form fiber winding technology. , why don't you try it?

Free-form filament winding process? Xia Yangjie's eyes lit up, Did they really say that?

The teacher threw the materials distributed at the meeting in front of Xia Yangjie, and said, Look for yourself, I don't understand this field either, so I don't know if what they said is right.

Xia Yangjie flipped through the information, and saw the question that the teacher mentioned at a glance. He read the explanation and requirements of the question twice at a glance, and felt a heat in his heart, so he stood up.

Mr. Hu, where are they? Xia Yangjie asked.

The teacher surnamed Hu pointed with his hand, and said, Mr. Qian sent them out, and the meeting should not be far away. Why, Xiao Xia, are you really going to find them?

I...I... Xia Yangjie hesitated twice, not knowing what to say. He smiled apologetically at Teacher Hu, then took out a notebook from the drawer, hugged it in his arms, and rushed out of the teaching and research room.

Old Hu, what's the matter with Xiao Xia? Someone noticed Xia Yangjie's strangeness and asked the teacher surnamed Hu.

The teacher surnamed Hu smiled and said: I just told Xiao Xia a few things about the meeting. Xiao Xia probably went after those two young people from the localization office.

Haha, I think Xiao Xia is quite compatible with them, and they are a bit unattainable. A teacher commented sourly.

You can't say it like this. People call it high-level and low-level. It's because you don't have the level of appreciation and can't hear the elegance. Another teacher said in the same weird tone.

Hehe, it's true that I'm high-spirited. However, it's better for me to be my lower class person. We can't get things that are sunny and snowy. The teacher in front said leisurely. These intellectuals of the older generation are all very good at classical prose. Although they are a group of people engaged in chemistry, they are no strangers to allusions.

Xia Yangjie didn't know what others were talking about him, even if he knew, he wouldn't care, because in the past few years, he had heard quite a few such comments both openly and secretly. He ran out of the office building, went outdoors, raised his eyes to look in the direction of the school gate, and saw two young men who were clearly dressed differently from the teachers and students of the school walking out side by side, and hurriedly chased after them. At this time, Qin Hai and Lu Xiaolin heard the footsteps behind them and stopped to look back. Xia Yangjie asked aloud, Excuse me, are you two from the localization office of Pusang?

Yes, we are localized, may I ask... Qin Hai asked calmly.

My name is Xia Yangjie, and I work in the Polymer Teaching and Research Section of the Department of Chemical Engineering. I study the theory of filament winding, but I am ashamed that I have made no achievements. I would like to ask, do you really want to do research on free-form filament winding technology? Xia Yangjie Replied upside down.

This chapter counts as the chapter at 8 o'clock in the morning, and I didn't expect to write it so difficult... Filament winding is a very complicated and complicated problem, and I almost looked stupid when I read the paper. I hope that the concept in the article is not wrong. As for the accuracy, let's avoid it. Finally... ask for a monthly ticket.