Chapter 90

With a little interest, elder martial brother Zhao asked, "do you have any good ideas?"

"Not yet. I just want to know."

Zhang Yuan doesn't dare to say that he wants to directly challenge this century's difficult problem, but the provincial plain faces ridicule Even if generally speaking, elder martial brother Zhao would not laugh at him, but would advise him not to do such a big problem.

Soon, two days went by

The spacecraft has successfully turned, the main engine suddenly shut down and entered a short maintenance state.

The artificial light from Europa shines on the light sail, making the whole Mothership slow down.

Light path, a great technology.

Because of this technology, small spacecraft can quickly travel between the moon and Jupiter without carrying a lot of fuel. In the past, at least half of the payload of a spacecraft from the moon to Jupiter had to be used for fuel. But now we don't have to. A small spacecraft with hundreds or thousands of tons can reach Jupiter from the moon in only one month, which is a great progress.

Zhang Yuan witnessed the slow extinction of the main engine.

It's like a pot of hot water has been doused. Without enough temperature, the bright light of plasma gradually goes out, and the nuclear fusion reaction automatically stops.

From this point of view, the fusion engine is quite safe. It will not explode and will only go out automatically when the reaction conditions are insufficient.

In the engine room of the earth age, only one sub engine and two molten salt stacks are left to provide basic power.

Molten salt reactor is a kind of nuclear fission value-added reactor, which has helped mankind through the long "gray age". The technology has been quite mature, so it is usually used as a backup energy. For the vital safety of spacecraft, it is impossible to rely on a single fusion energy.

In the next period of time, the relevant technical personnel will carry out a series of maintenance on the whole engine.

The whole internship in the engine room is over

Zhang Yuan went back to the living area a little dazed.

He has a few days of vacation to rest, and then he has to go to work in the nuclear power plant. Anyway, it's not too big. He's going to stay at home and read his paper.

Well, after reading the literature for several days, he has no idea. After all, it's a world-class problem

At six o'clock in the evening, a small dinner is being held in the "big bucket restaurant" in area A.

No matter how busy academician Ding is, at the beginning of every month, he will take some time to invite everyone to have a meal and pay attention to the condition of some disciples.

"Are you trying to do turbulence problems?"

"Just want to know..." Facing his teacher, Zhang Yuan said honestly.

Ding Zhaodong smiles, perhaps remembering that when he was young and frivolous, he didn't hit the young disciple.

"It's really a very difficult problem. Many people have studied it for more than ten years, but they can't write very good articles, wasting their time in vain. If you want to do something in this area, you have to be mentally prepared. "

"If you don't know anything about mathematics, you can ask elder martial brother Luo Wenhao, or you can ask me directly."

Elder martial brother Luo, who is nearly 40 years old, has graduated from doctor's degree for a long time. He is very busy with his work and seldom attends such gatherings.

Zhang Yuan met him for the first time.

Elder martial brother Luo is a great man who is engaged in the research of information field. However, his direction is inclined to mathematics, and he is quite famous in the study of positive curvature, solving two famous Hopf conjectures.

Why two? Because there are many Hopf conjectures, one is "there is no curvature measure of normal section on S ^ 2xs ^ 2", the other is: "the Euler characteristic numbers of even dimensional positive curvature manifolds are positive".

Two guesses, could have won two awards, the result was his one pot.

Zhang Yuan was awed and had a desire to hold his thigh.

"Elder martial brother Luo!"

"Turbulence problem, ha ha, ambition! I like to make friends with these young people with ideals. I've studied this before. "

Around him sat the wife of elder martial brother Luo, a woman mathematician in her thirties. She was elegantly dressed and had a special Victorian flavor.

"Hello. Are you a classmate Zhang with 300 kg of gold? "

Zhang Yuan said with a smile, "Ms. Mo, don't be kidding. In fact, I prefer to have 300 kg of antimatter, which can be used for experiments."

"Yes? Antimatter is too expensive You have a high reputation among the girls in our f district! Do you want me to introduce you? "

Zhang Yuan couldn't help but feel a little embarrassed, "girls from LAN Kingdom, there are several choices in my address book..."

Everyone laughed.

The atmosphere at the dinner table was very relaxed. First we talked about personal development in the near future, and then we talked about some academic gossip. It was very interesting.It includes some mathematical problems proved by someone, a new breakthrough in condensed matter physics, and the famous journal of modern science, whose academic corruption has been found out, whose influence has plummeted and so on.

"More and more people are suffering from depression. If diagnosed, they will get off the spaceship on Europa and return to earth."

"So..."

"Modern science has been suspended for the time being, and several reviewers and editors have been checked. They have submitted contributions there before I didn't expect this to happen. "

"Academic corruption can exist everywhere. It's hard to avoid It mainly depends on the human environment. "

Zhang Yuan was surprised that the journal's influence had fallen sharply, which was not related to what happened to him, was it?

However, I found that everyone did not focus on him, so I gradually relaxed.

At the end of the dinner, Zhang Yuan had a discussion with his new elder martial brother Luo.

"The main problem of turbulence is the direction of non-uniform turbulence. After reading the paper, I first thought of Fourier analysis and related integral transformation. Later I found that it was not quite right... "

This is his intuitive idea.

"Fourier analysis, too ordinary." Elder martial brother Luo said with a smile: "I thought about it at that time. Later, I found that it was only suitable for uniform turbulence. Even if it was made, the fitting effect would not be very good. It was of little significance."

Zhang yuanzan said: "it's good to use it as a test paper."

When elder martial brother Luo patted his head, he seemed to think of something, "it's not easy to use the method of pure number. If it's direct numerical calculation, I've seen a good idea, using les and using the wall function of non equilibrium and equilibrium respectively..."

"The influence of three different grid conditions on the calculation of wall parameters, and the comparison with the corresponding DNS results This is an innovative algorithm in recent years, but in practical application, it is worse than your father's algorithm. "

Zhang Yuan suddenly had a flash of inspiration, as if he had grasped something, "meshing?"

"Then, can we divide the whole observation results into some kind of communities, and first decompose the whole big problem into small problems..."

"Community?"

Elder martial brother Luo was stunned for a moment, "but in the end, you still have to merge the whole problem back, otherwise all the data will be meaningless. What is the method of division and merger? "

"Well I haven't thought about it yet. "