The military-industrial scientific research system of the academic master

Chapter 1284 The little wonders of the shock wave wind tunnel

Chang Haonan was not prepared to fully take over the development of solid rocket boosters, so at the meeting he only asked Lin Chenggang to select important information and send it over.

The other party's actions were also very agile. That afternoon, they sent three confidential personnel to deliver a batch of screened documents and information to the Torch Laboratory.

Although it has been screened, various storage devices and some necessary paper documents are still packed into a large password box.

After completing the handover, he immediately got into the computer room and began to verify his conjecture at the meeting yesterday.

It wasn't until dinner time the next day that Chang Haonan returned to the office, and then called his founding disciple, Li Yabo.

Thanks to the experience and knowledge accumulated during his doctoral studies, the latter quickly turned to theoretical research after graduation.

Due to his strong ability and very few confidential research fields, he is able to publish many high-level articles every year, many of which are in top journals such as Science or Nature. As early as two years ago, he was naturally promoted to associate professor. job title.

In addition, because Yao Mengna is currently raising a baby at home, and the other teachers in the laboratory are responsible for projects outside the home, he has gradually begun to take charge of the daily scientific research work of the laboratory.

"Teacher, you are looking for me."

Li Yabo walked in lightly.

"Yes, you sit down first."

Chang Haonan nodded, tapped the pile of paper he had just printed out on the table, and placed it in front of the other party:

"Yabo, take a look at these articles. They are related to the oxidation behavior of metal materials."

In fact, he had some plans for the next step.

However, in order to avoid Li Yabo from making preconceived judgments, and of course to let the other party understand the basic situation, no more specific instructions were issued immediately.

However, after Li Yabo lowered his head and glanced at the title of the paper, he was stunned for a moment, then quickly flipped through it, then raised his head and looked at Chang Haonan:

"Teacher, I have read these papers before..."

Now it was Chang Haonan's turn to be surprised:

"Have you seen them all?"

Li Yabo nodded:

"In fact, I was even the one responsible for reviewing the latest article..."

“…”

Chang Haonan suddenly had the feeling that "when children grow up, they also learn to pretend to be invisible."

"Okay...then I'll just tell you."

He cast his eyes on the preliminary calculation results on the monitor screen next to him:

"I need you to follow their ideas and re-verify the AP/HTPB/AI system...or, by extension, the energy release characteristics and oxidation reaction mechanism of all aluminum-based system solid propellants."

Hearing this request, Li Yabo's eyes flashed with surprise.

Based on his understanding of his teacher, this "re-verification" does not mean simply repeating the other party's experimental content according to the content of the paper.

Rather, we need to produce different results for the same research object.

"You mean...there's something wrong with their experiments and characterizations?"

As a reviewer of one of the articles, Li Yabo was very confident that there would be no serious errors in the analysis and derivation process.

However, reviewers and editors will not be responsible for verifying the data in the paper, so if something goes wrong, it is most likely a problem in this area.

Chang Haonan took a deep breath and organized the language in his mind:

"I'm not sure if there are any problems with the data, but their study on the mechanism of the thermal decomposition process of the three-component AP/HTPB/Al propellant, which is the main premise of the entire analysis process and decomposition kinetic calculations, is consistent with my molecular simulation results. Not very good…”

"ah?"

Li Yabo's eyes almost darkened when he heard this judgment.

This is equivalent to directly misapplying the first formula when doing physics problems. Then no matter how accurate the subsequent process is, it will only go further and further away.

"But are the dynamic parameters they finally calculated consistent with the Kissinger equation and the Ozawa equation?" "It's hard to say..."

Chang Haonan shook his head:

"It may be that the conclusions were drawn first and then the experiment was done, so some fine-tuning was done to the data, or it may be that a blind cat encountered a dead mouse... You should know that for this kind of research topic, even if you just set up a theoretical model, If you do forced fitting, as long as it’s not too outrageous, you can still get close to it.”

"this…"

Li Yabo already had an unbearable expression on his face:

"But the papers published by MIT... won't make such low-level mistakes, right?"

Due to the requirements for the publication cycle of papers and the basic trust among peers, in addition to the authenticity of the data, reviewers will basically not consider situations like what Chang Haonan said.

To a certain extent, it is part of the fool-killing master.

"This is not a stupid mistake..."

Chang Haonan curled his lips:

"This part of the content has little to do with the macroscopic combustion characteristics. Instead, it has to do with the microscopic mechanism... Even if there are colleagues to verify it, as long as it is not actually filled into the engine, the results will not be obviously wrong, and even if it is ten thousand Once someone who is engaged in chemistry finds a problem, they can also explain that the focus of this article is on engineering theory rather than pure theory..."

6◇9◇Book◇Bar

Hearing this, Li Yabo could only lament that he was still too young after all:

"Then what do you mean..."

"Further decompose the thermal decomposition process into three processes and recalculate it."

Chang Haonan took a piece of paper from the side, with several lines already written on it:

"The first stage is the slow weight loss stage at low temperature. During this process, the AP component will undergo a solid-solid phase change from cubic to orthorhombic;"

“The second stage is the rapid weight loss stage at medium temperature. On the one hand, HTPB begins to undergo an endothermic melting reaction, which plays a certain antagonistic role in the exothermic decomposition reaction of AP. At the same time, HTPB begins to coat the crystal surface of AP, causing the The local decomposition reaction is affected, which has the effect of weakening the activation of the latter's possible reaction center;"

"The third stage is the stage of slow weight gain at high temperature, that is, the remaining small amount of HTPB begins to further decompose, some aluminum particles melt, and gradually begins to undergo slow to violent oxidation..."

“…”

Li Yabo did not just look at the page in front of him, but quickly took a pen and began to add content next to it...

It wasn't until about half an hour later that Chang Haonan, who was already a little dry, finally stopped describing.

The piece of paper in front of Li Yabo has already turned into a notebook...

"Then I'll do it right away..."

He reviewed the contents of the notebook again and then stood up.

But he was immediately stopped by Chang Haonan from behind:

"Wait a moment."

Li Yabo turned around:

"Teacher, is there anything else I need to pay attention to?"

Chang Haonan took out an envelope from the drawer:

"I will write you a letter of introduction. When you do the combustion characteristics experiment, remember to go to the Institute of Mechanics of the Academy of Sciences and use a shock tube for ignition. This can make the heating process much shorter than the ignition delay time of solid fuel, and it can also It can restore the pressure environment when the actual engine is working, which is much more realistic than the flat flame burner and laser ignition..."

And because Chang Haonan never said that this research was related to the hypersonic weapons project, Li Yabo hadn't reacted too well at this time. He hesitated slightly with the envelope in his hand:

"As for the shock tube... there is one in the Aerodynamic Science and Technology Laboratory of our school next door, and the director of the laboratory has worked with us many times, and we are familiar with both the business and the process..."

He was only halfway through his words when he was interrupted by Chang Haonan waving his hand:

"The performance of the one in our school is not enough. I need an initial working pressure of 25-30 ATMs. Currently, let alone China, only Huairou in the world can meet the requirements."

In fact, this can be regarded as some benefits brought by the development process of ultra-high-speed wind tunnel.

Apart from China, there is currently no other country that has such abundant resources that can use high-performance shock wave generating devices for the study of combustion chemical kinetics.

Until this time, Li Yabo finally realized something, and the expression on his face gradually became solemn:

"I see…"

(End of chapter)