What was somewhat unexpected by Chang Haonan was that in addition to Guihang, who was completely in a hurry, there were also people who moved just as fast.

Just three days after the joint meeting of the three departments, he received a politely worded letter of application from his office at BJA.

It was sent over through a military line.

The letter came from Jinling University of Science and Technology and the General Armament Department, which had only been established for a few months.

The sender who finally signed the letter was called Rui Xiaoting.

In fact, he can be regarded as crooked.

Because the content is to invite Chang Haonan to provide theoretical and numerical calculation consultation on a "multi-body system emission dynamics problem".

It's still the kind that gives a consultation fee.

There is no direct mention of the new software that Chang Haonan is in the process of writing.

However, judging from the content of the feedback on paper, it should be a joint application of the transfer matrix method and the finite element method involving the discrete time of some controlled system.

Although the transfer matrix method has not been directly included in the database, Chang Haonan has considered when designing the software that some unpopular directions may have some non-universal calculation methods, so he specially set aside a few custom interfaces.

As long as the user has the corresponding algorithm design and programming ability, he can add his own simulation method to the software.

It can also be used in conjunction with variable discrete or variable separation methods that are already available in the software.

So that's exactly what his current research direction can address.

It's even more suitable than the high-level trainer on Guihang's side.

After all, the latter is actually no longer challenging for Chang Haonan, even if he doesn't have the new software at hand, he can completely rely on the old methods and experience to solve it.

As for the specific projects involved behind this question......

Although the launch dynamics of the multi-body system is a rather vague statement, considering the nature of Jinling University of Science and Technology and the rise of another general armament department, the result is not difficult to guess.

In general, it is inseparable from two things: rockets or missiles.

So after a moment of thought, he decided to let the other party come over first, so that he could understand the situation in person.

The main thing is that the work at hand is progressing rapidly with the help of Xu Yang and several other main forces of the calculation institute, and it has reached the point where he has to stop and wait for others.

……

As a counterpart engaged in the military industry, the other party also showed a considerable degree of vigor and resoluteness.

Two days after the reply letter was sent, Professor Rui Xiaoting came to the supercomputing center of Jinghang University with a person who looked like a student.

After meeting, this time, Chang Haonan was a little surprised.

Judging from the content of the initial application letter, the sender should be the person in charge of the entire equipment type, not a specific model.

Generally speaking, those who can sit in this position basically have to be bigwigs with sufficient qualifications and levels.

But the person in front of him looked quite young, at most in his thirties and less than forty years old.

Excluding Chang Haonan's own outliers, he can definitely be regarded as a young talent.

And Rui Xiaoting had actually done his homework before writing the application letter, and now he saw that although the real person was still affected by some mental shock, he was mentally prepared after all.

"Hello Director Chang, thank you very much for accepting our application."

"After I saw your letter Professor Rui, I was looking forward to meeting you sooner, but I didn't expect you to move so quickly."

The two shook hands tightly, briefly said a few polite words when they had just met, and then sat down on the two sofas in the reception room of the supercomputer center.

"Alas, there is no way, the time is tight and the task is heavy, Party A's side is in a hurry, otherwise I won't come over on Saturday afternoon to disturb your rest."

Rui Xiaoting said, took out a laptop from the bag behind him and put it on the table, turned on the screen and pointed the screen towards Chang Haonan:

"I'll make a long story short and introduce the specifics of our subject, there are some things that are not easy to write on paper."

"I guess, maybe it's a multiple rocket launcher?"

Chang Haonan looked at the Windows system that was reading the strip and said his previous guess.

Computers in this era are more user-friendly and will leave plenty of time for users to communicate.

This made Rui Xiaoting a little surprised for the first time:

"That's right, it seems that Director Chang is also involved in the field of multibody dynamics?"

"Sort of, from the point of view of numerical calculations, there are some similarities with the problems I studied before, of course, if you really want to talk about it, you must be inferior to experts in your field."

Chang Haonan, who confirmed his guess, was not prepared to take the lead today, he just wanted to verify the efficiency of his software in the face of real problems.

"If you know, you can save the most important part of my speech."

Rui Xiaoting sighed lightly when he said this:

"As soon as many people heard that they were researching artillery equipment, they felt that the technical content was not high, and that the funds we received were not much, and the priority of scientific research was not at the forefront."

"To be honest, I didn't expect to receive a response quickly before sending the application letter this time, but the next day I received a call from the General Armament Department, asking us to fly to the capital to meet you immediately."

Chang Haonan, who has been engaged in aviation for two lifetimes, has never had such an experience, and he really doesn't feel very sympathetic, so he had to change the direction of the topic slightly:

"Rocket artillery, it is still not the same as ordinary artillery equipment, and the technical difficulty is great, especially long-range rocket artillery, and the design difficulty is probably not lower than that of ordinary tactical missiles."

Long-range rocket artillery may be somewhat similar to tactical ballistic missiles in terms of look and feel and military use, but from an engineering point of view, they are two completely different pieces of equipment, and there is a world of difference in the orientation of optimizing performance.

Hearing that Chang Haonan actually had such a point of view, Rui Xiaoting's whole person was directly in good spirits, and even had a feeling that Boya had finally met his son:

"Yes, yes, because of the large ballistic height of long-range rockets, they even have to enter a section of the stratosphere, and the missile itself has to spin to maintain stability, not to mention the extremely complex flight dynamics equation, because it also takes into account the transient situation of the launch tube during continuous launch, as well as the interference between multiple rockets, the complexity of the problem is much greater than laymen think."

When the two of them chatted here, the computer finally finished turning on.

"I wonder if Director Chang has heard of our country's 'Guardian' series of rocket launchers?"

"The kind that was successfully exported to Turkey last year?"

Chang Haonan on this timeline has actually not been exposed to relevant information, but he has seen a lot of reports on this before he was reborn.

"Yes, it is also after we have proved that our products have the potential to earn foreign exchange for export, and the degree of attention has been higher, otherwise we may not even have the opportunity to send you a letter to apply."

Rui Xiaoting gestured to the graduate student who came with him next to him.

The latter immediately took out a paper material from the bag behind him and handed it to Chang Haonan.

Seems to be a technical manual.

"Before coming, Xiao Li originally said that he might need to introduce the nature of our products in detail, so he brought such a thing and left it for you as a souvenir."

It's really a technical manual.

It's a pity that Chang Haonan doesn't have a real guy at hand for practice.

"The topic we are studying now is to comprehensively upgrade the previous basic model, that is, the Defender 1, to create a long-range rocket artillery that is more advanced in performance and can even be used as a replacement for ballistic missiles for some small and medium-sized countries!"

(End of chapter)