Chapter 293 Chang’s Model

When Chang Haonan walked out of Tang Lintian's office, he still felt a little unreal.

In his previous life, he worked from school to research institute, but he had never experienced this kind of efficiency. From entering the door to greetings to making a request and finally getting the agreement, it took less than 10 minutes in total.

The tea was still warm when we left.

Standing in the corridor of the aircraft building, Chang Haonan was a little confused about what he should do in the afternoon.

Before talking to Tang Lintian about the database, he had been thinking about buying a mobile phone and applying for a number.

Two of the three major operators that everyone later became familiar with did not yet exist at this time - China Mobile would not be established until 1999, and China Unicom would not be established until 2000.

In 1997, only China Telecom provided commercial mobile phone services. This company only became independent from the General Administration of Posts and Telecommunications in 94. It has only been three years since then. It still has a strong official-like feel, such as not working on weekends.

So this matter can only be done tomorrow.

The computer room was still being renovated, so there wasn't anything he needed to deal with.

After thinking for a moment, Chang Haonan remembered that just before he left, Tang Lintian asked insinuatingly about the progress of compiling the textbook...

Finally he decided to go find Liu Hongbo.

According to the impression from his previous life, this teacher almost never had a day off before he got married.

Sure enough, it only took more than ten minutes, and after continuously searching several places where the other party often appeared, Chang Haonan found Liu Hongbo in the student office.

"Teacher Liu, good afternoon."

Although the two of them always addressed each other as seniors and juniors when they met, this was after all in front of other people's students. Chang Haonan thought about it and decided that there was no need to put on the airs of this senior uncle.

Moreover, in fact, the title "Teacher

"Junior brother?"

Liu Hongbo himself didn't care about this. When he saw that the person coming was Chang Haonan, he was also surprised:

"You came back at the right time. I just have a lot of questions to ask you."

"About the textbook?"

Chang Haonan wanted to know why the other party was so distressed.

Speaking of which, he did not do it properly. The original plan was to come back and help compile the teaching materials together after finishing his work in Haojing. However, there suddenly came a project at the 14th Institute, so in the end he had to let Liu Hongbo do it himself. I worked hard for two months.

"Yes, I almost finished the first five chapters according to the outline and ideas you gave me, that is, from the introduction to the linear analysis of solid mechanics and structural mechanics, but from

Liu Hongbo handed a piece of information he was holding to the student, and then took Chang Haonan back to his office.

It should be said that this efficiency is quite good, because the latter's outline has a total of twelve chapters, of which the last chapter is a program example. You can just copy and paste it, leaving eleven chapters.

In terms of length alone, nearly half of it has been completed in two months.

Of course, if you consider the difficulty of compilation, it may only be about a quarter...

On the desk, the computer screen is showing a dense pile of tubes that are constantly winding and stretching.

Chang Haonan remembered that this thing seemed to be called a three-dimensional pipe, and it was a screen saver that many people liked to use back then.

Due to its mechanical problems, CRT monitors, if the screen remains motionless for a long time, the electron beam will bombard the same position of the phosphor layer for a long time, causing the screen to accelerate aging. Various screen savers are designed to avoid this happening.

But for Chang Haonan, this is indeed a long time ago.

In later generations, only certain brands of OLED screens will experience a similar "screen burn" phenomenon, and screensavers have gradually become a historical term, although Juhardware still retains it in Windows 11.

Of course Liu Hongbo didn't know that Chang Haonan was thinking about so many things during the few seconds he stared at the screen. He shook the mouse twice to end the screensaver and then entered the password.

The content displayed on the screen was replaced by a Word document.

But this page only has a title.

"General Methods of Nonlinear Analysis"

There is nothing below.

"I have rewritten this part for the third time. No matter what ideas I use, the feedback I get is basically the same. I just can't understand it."

Liu Hongbo, who looked distressed, pulled Chang Haonan to his chair and asked the latter to sit on it. Then he moved a stool to the corner and sat next to him:

"I think we can consider starting directly with the solution of the equilibrium equation and skip the nonlinear analysis part?"

"In addition, there is a section below, finite element analysis of heat transfer, field and incompressible fluid flow problems. I think this chapter has nothing to do with the theme of our textbook. These aspects are rarely used in the aircraft design process. "

"besides……"

Obviously, Liu Hongbo was very careful in the process of writing this textbook.

Otherwise, he would just pile up all kinds of theories and do some random examples, and that would be it. He would not encounter these troubles at all, let alone make any suggestions.

However, these designs of Chang Haonan are naturally well thought out, and many of them are pitfalls that he and his colleagues have stepped on before.

"How about that? The three prerequisites for linear analysis are that the displacement of the analysis object is infinitesimal, the material has linear elastic properties, and the boundary conditions remain unchanged during the entire process. But for most problems, especially those involving large deformations , this assumption simply does not hold.”

Chang Haonan immediately shook his head. He would never give up on the corresponding request because of the difficulty.

Because life is not a game, and there is no story mode difficulty option. If it is not taught in school, it can only be learned at work.

But at that time, it was not as simple as passing a course.

"Not to mention, when I did the wing flutter analysis for the MA-60 last year, I used a combination of nonlinear finite elements and nonlinear beam models. If you haven't even learned the basic theory, how can you solve the practical problem? When there is a problem, you will definitely suffer a big loss.”

“But we also have to consider students’ acceptance.”

Liu Hongbo tugged at his thick hair:

"The model you proposed is now called Chang's model in our industry. That is to say, the teacher suppressed the original results and did not publish them publicly. Otherwise, you might be able to become a fellow of the American Society of Civil Engineers... You can't count on that. All students are on the same standard as you.”

"I don't have that thing..."

Chang Haonan waved his hands and was about to say that he was not interested, but suddenly he noticed a question:

“Wait, why the Society of Civil Engineers?”