Chapter 319: Find it out, Kobayashi, I'm your superior

At 12 o'clock, YF-87 returned to zero for the second time, and the seminar on improving the route officially began.
Although Li Zheng has gone deep in the data field, just like the last time, he doesn't know what the results he got, just like an artificial intelligence machine, and he doesn't know the language representation he gives back. What's the meaning.
In the eyes of the engineers of the Seventeenth Research Institute, the crack images and data obtained from these disassembly inspections clearly pointed to a unique result-
Synchronous precession.
In the aerospace field, the effect of this word is equivalent to Cthulhu's whispering...
A scary and unreasonable existence.
Among them, "precession" can also be called "vibration".
Speaking of vibration, this is an old friend of aerospace, which is equivalent to BUG to programmers and probability to mobile game players.
During the launch process, the rocket will encounter various vibrations, and the structure and materials have their limits and cannot withstand large vibrations.
In the design stage, these complex situations will of course be taken into consideration and various vibration reduction measures will be used. Huang Er also adopted the latest damping and variable energy accumulators to suppress vibration.
Under normal circumstances, there is no problem with this design, and 8.8 is a success with a little luck.
But in the harshest vibration environment, the engine made a whisper of Cthulhu unexpectedly...
This low groan sank to the sea during the first launch and was not caught by anyone.
In the recent shafting fracture accident, it was covered by countless huge noises, and it was also impossible to capture.
But Liu Rui used his terrifying perseverance to capture clues in other test data.
On this basis, Li Zheng used mathematics and algorithm tools to extract features, and expanded the scope of screening to all historical data ever since.
As he said, this kind of "groaning" is meaningless to take out, just like the wind blowing leaves, but it is piled up countless times...
He finally heard Cthulhu's voice.
It's just sound in mathematical form.
Next, Zhu Mingyue went one step further and translated this low chant into engineering language
In a harsh vibration environment, when the turbine rotor runs at a supercritical speed, the local dynamics and material properties have some wonderful changes, resulting in a change in its natural vibration frequency, and then coupling resonance with the operating frequency.
This also means that this part has "rebellion", trying to rotate and vibrate in its own way.
In this process, the turbine rotor is bound to bear huge structural stress.
Those cracks that are so subtle that they are invisible are just generated.
When the resonance is violent to a certain extent, and the structural stress exceeds the yield limit of the material, the crack will expand rapidly and then break in the violent rotation.
What's more frightening is that subsynchronous precession is still a self-excited vibration, which will produce greater vibration due to vibration.
It is like 100 Liu Xiang holding hands to form a circle, running clockwise, according to the requirements, running a circle in 1 minute.
Because they are all Liu Xiang, this speed is nothing to them, so they run very happily.
But suddenly!
You are too beautiful to hear a chicken.
One of them, Liu Xiang, suddenly became an idol.
Start singing and dancing!
At this time, it became 99 Liu Xiang and a singing and dancing idol running in circles.
But this will not collapse.
After all, Liu Xiang next to him will drag the idol to run together. Although it is a little tired, 99 Liu Xiang can still withstand an idol.
However, the scary thing is that the man who was dragged away is an idol.
He would not honestly spread his arms out of the air and be dragged by Liu Xiang before and after.
He wants to sing and dance.
In fact, at the same time he turned into an idol, he sang the next song You are so beautiful.
In an instant, the two Liu Xiangs on his left and right were infected and began to sing and dance.
The dancers suddenly became three, which made the runners next to them miserable.
But this is just the beginning.
More chickens, you are so beautiful, you have already come in waves...
When the jumper content is 1%, this circling run can still be maintained, and only a few runners will have imperceptible muscle tears.
When the content reaches 3%, runners can already feel the pain of arm pulling.
When the content reaches 5%, the pulling force will reach the endurance limit of the runner, and either let go or break the arm.
This is self-oscillation, which is both the cause and the result.
Where did the original "chicken you are too beautiful" come from and how to avoid it is still an engineering problem.
Just like a middle-aged person staying at home, there will always be an idol's name on his face.
Since then, the accident logic has been completely clear.
In the meeting room, Zhu Mingyue also carried out reflection and summary.
"In the first zeroing, we did not find small local cracks, only the damage to the exhaust system."
"From the current point of view, the problem with the exhaust system is not isolated at all. It is a chain reaction caused by the resonance of the turbine system, but the exhaust system was relatively fragile at that time and broke before the turbine broke."
"There is no doubt that this is the direct cause of the 8.8 launch failure, but it is by no means the root cause."
"After 8.8, the first reset to zero started. In our analysis and processing, there was a serious fluke mentality. We made the mistake of treating the head and feet. We only unilaterally strengthened the exhaust system. A patient with pneumonia prescribed cough medicine."
"Finally, in the 10.5 test run, the shaft system was completely broken."
"I personally, and the YF-87 team from the 17th Institute, cannot escape the blame."
"But although I am in the position of a sinner, I still want to thank the comrades of the First Hospital for their hard work in the zero-return task."
"Among them, two comrades Li Zheng and Lin Yujing have made outstanding contributions. Through in-depth data analysis, they have obtained the pulse twice and sent the pulse to my eyes, but I am personally eager for success and failed Digging deeper on this basis, and only thinking about guilt and meritorious service as soon as possible, caused Huang Er to fall into the current dilemma. I know there is no point in apologizing, but..."
Zhu Mingyue stood up and bowed deeply to the audience.
"Dear leaders, comrades, I'm sorry."
The people in the entire conference room also stood up almost at the same time, and did not intend to accept the apology.
"Alright." Zhao Zhenhua personally stepped forward, helped Zhu Mingyue back, waved to the audience, "Sit down, sit down, sit down."
After everyone was seated, Zhao Zhenhua sighed and said:
"I also have the responsibility. I pressed too hard."
"In fact, when the fault model was determined for the first time, Zhang Zhicheng believed that the accident was not simple. This exhaust system has been tested and will not lose the chain for no reason."
"His opinion is to spend about half a month to study the causes in depth."
"it's me."
"It was me at the time. I rejected this opinion and asked to improve the exhaust system as soon as possible and test the car as soon as possible."
"So, none of you should have any psychological burden."
"I said at the beginning, I set the route, follow me, and I will be responsible if something goes wrong."
"It's the same now. This responsibility is mine. This should be implemented in the report. It was not Zhu Mingyue, Zhang Zhicheng, or Zhao Zhenhua who was eager for success before."
"So you guys, don't hesitate, don't feel guilty." Zhao Zhenhua waved his arms vigorously, "Fuck it for me. If you change it, if something happens again, I will be the best!"
Zhao Zhenhua's words aroused the emotions of the participants again. Regardless of age, the eyes were a little wet and red.
The chief of the first hospital, can achieve this level, what else can he hesitate?
Fight!
With this momentum, Zhu Mingyue proposed three routes.
One is to hit steel plates to strengthen the entire shaft system.
Second, redesign to bypass this problem.
Third, list all possible causes of resonance, and carpet partial improvements.
Obviously, Zhu Mingyue has mentioned the first two routes before.
Even if it is determined that the cause is the subsynchronous precession, there is no clear solution in the world. It is still the frontier field in engineering design, otherwise Cthulhu's groan will not be used to describe it.
It can be said that facing this problem, there is no 100% guaranteed solution, even if there is no 90% solution.
Therefore, even if he did not know the cause, Zhu Mingyue had already proposed one or two ways.
As for the third road, it is full of "gambling" on the surface.
To this end, Zhu Mingyue used the most exquisite language to describe the root cause
【In the limit state, the local properties of the turbine rotor change. 】
Perhaps such a change will not happen if the structure is changed a little bit.
Maybe the shaft material slightly reduces the proportion of a certain element and it will not happen.
Maybe it's internal damping, maybe it's dry friction, maybe it's the aeroelastic effect of the turbine tip...
Now Huang Er is facing such an inspired and inconclusive situation.
What lies ahead is aerospace, the unknown territory of the entire engineering.
What they can do is just like every predecessor before—
guess.
test.
There is nothing more gambling than this.
There is nothing more representative of science than this.
And Zhao Zhenhua.
Whether he is a scientist or not is unknown.
But it must be an old gambler.
An old gambler who has gone through ups and downs and became the top gambler.
There must be a lucky factor in this, but it is also inseparable from the judgment of the critical moment.
In his vision, the three plans represent three ideas, three costs, and three results.
First, carry the past and thicken the steel plate. The price is to give up the load advantage of the hydrogen-oxygen engine. As a result, you may struggle to temporarily keep your position, but stifle the future potential of the Yellow River series.
Second, go around and design from scratch. The price is to postpone the hydrogen-oxygen engine technology for five years, and the result will be its own death. However, the Yellow River series may usher in a new life after a few years, when the technology and resources are more abundant.
Third, touch the past and cross the river by touching the stones. The price is to sacrifice the last time of the Huang Er team and the last authority of oneself. The result is -
Winner and loser.
It is not only Huang Er's road ahead, but also a big technological leap.
Losing is nothing more than retiring in verbal abuse, ridicule and indifference.
Before today, how could such an old gambler like Zhao Zhenhua know that there is a third way?
It’s just hope that it’s too elusive. Crossing the river by touching the stones, the water is so deep, where can you touch the stones by such a coincidence? More often, it will only sink to the bottom, not even a blister.
Even the old gamblers don't dare to make a rash move.
But now, he seemed to see Ruoruuowu water patterns and felt the outline of the stone.
In gambler terms-
The feel is coming.
But I can't make it yet...
The more this is the time, the more stable it is.
Zhao Zhenhua looked at Shen Tinglan: "When will the YF-100 used in the 927 enter the production stage at the earliest?"
"Ah..." Shen Tinglan said blankly, "My position...my identity...this..."
After being at a loss, Shen Tinglan finally sighed and said in a modest volume: "The earliest planned date is mid-December. The variables depend on the YF-100 team. Zhu Gong should have more news than me."
"Then suppose it is December 15." Zhao Zhenhua scanned the rest of the people. "It is October 30. There are 46 days, 46 days left. How far can we improve?"
No one dares to answer this question.
Some conjectures have to be put forward first, and then experiments are carried out. Now even the first conjecture has not yet started.
After the people of the 17th Institute were thinking hard, Shen Tinglan spoke first: "Imagine that all improvements are focused on rotor damping and vibration reduction, and possible materials and structures are replaced at the same level. Finally, the workload is demonstrated... It’s huge, but it’s better than the madness that has been so long before."
Her thoughts seemed to wake up Zhu Mingyue.
"We are confident to complete the work mentioned by Master Shen within 46 days."
Feeling coming, the east wind blows, Zhao Zhenhua no longer has the slightest hesitation, clapping the table and saying:
"Then go!"
"Give me all!"
"Again."
"My route, I'll be responsible if something goes wrong!"
"Don't give up my old face."
"If you dare to come up with a plan, I will dare to go to the group to shoot the chairman's table!"
"As soon as the plan comes out, I promise to start the factory."
"Whoever dares to block the way, I will put my back when I die!"
At the end of the road, the willows are in the dark.
Zhao Zhenhua Stud, don't want to be casual.
Of course, people who can be in this room at this time can't shrink back at all.
"on!"
"There are already ideas in my mind."
"With the words of the secretary, how about one more year!"
"Well!"
Even Lin Yujing shouted with the others.
When the mood calmed down, Zhu Mingyue said immediately: "Okay, then everyone should hurry up and go to the restaurant to eat something, and make work arrangements immediately after returning."
After that, he turned to Zhao Zhenhua: "Secretary, you..."
"I'm going to do something to create momentum..." Zhao Zhenhua stood up, "you can't just rush in and shoot the table...it has to be brewed, and prepare for the group leaders... At least let them feel our side. Make a breakthrough and set off your emotions."
In the laughter of everyone, Zhao Zhenhua did not forget to name Li Zheng before leaving.
"I don't know if it is a coincidence or a long-term vision. How can I think that Harbin Institute of Technology can do a lot in this process?"
Li Zheng humbly scratched his head: "This, in fact, has far-sighted elements in it. Even if I don't know the cause of the accident reported today, I am very clear that this issue has touched the current technical boundary. Harbin Institute of Technology is the most domestically done in this regard. Far."
"If you say you are fat, you are still breathing!" Zhao Zhenhua scolded and rushed around, "Li Zheng, have you already seen it? You should cooperate with the follow-up work. If you don't believe him, you have to believe that Harbin Institute of Technology is not."
"Of course." Zhu Mingyue hurriedly got up to send him off, "This... we still need Master Shen to provide guidance..."
"If she doesn't leave, I will leave." Zhao Zhenhua raised his hand, "but after all, Tinglan still has 927 jobs, I wonder...Before 12 o'clock, don't leave others overnight. It's not appropriate."
Shen Tinglan was taken aback, looked at his watch and said, "Lao Liang told me to go back before 3pm..."
Zhao Zhenhua pressed his hand confidently: "You got it wrong, and he told you to go back tomorrow."
"Then... Then I believe it."
A bunch of people sent farewell to Zhao Zhenhua and flocked to the restaurant.
Although there were only leftovers leftovers, everyone was eating steaming hot.
It was Chen Hongbing's rare embarrassment. He didn't have a chance to speak, and he didn't know why he came.
However, he is also very excited. Once the new engine is successfully tested, Huang Er puts on the schedule again and enters the launch preparation stage, that is when he Chen Hongbing makes a comeback!
But when it comes to embarrassment.
Chen Hongbing must not be the most embarrassing.
Du Songtao stirred the cold meal by himself, in a daze, feeling that he was too much.
Obviously it is here to turn the tide... but it seems that Mao didn't do it, so he was not helpful?
There were originally two small subordinates, but now they are also independent...
What should I do next? Does it account for the office air conditioning?
In self-doubt, a humble figure sat opposite him, and an arrogant figure sat diagonally opposite him.
"Yeah." Li Zheng set the plate and said hello, "Little Du, do you want to come to our group?"
"Gan..." Du Songtao laughed at himself and shook his head, "This is a complete defeat of Inspiration Flow in the face of Diligence Flow..."
"No, it's not..." Lin Yujing sat in the place farthest away from Du Songtao, holding his forehead with some embarrassment. So many math problems..."
"Ah." Du Songtao sighed, "Xiao Lin still understands me very well... Or go back to me, don't waste your youth in the Li Zheng team."
"Um..." Lin Yujing shrank as she grabbed the dinner plate, "The Sporeman gets up and starts, and would rather enter the Xian group than the Spore Monster."
"Speaking of group..." Li Zheng sullied his head and drank a bowl of egg soup, then pushed the bowl to Lin Yujing, "Xiao Lin, give me a bowl of soup."
"???"
"Leader." Li Zheng pointed to himself, "Find out, Xiaolin, I am your superior."
"Bah!" Lin Yujing squeezed her face and sprayed water frantically.
But Liu Rui happily crossed over and sat beside Du Songtao.
"It's arranged, I'm messing with you, Li Zheng."
Li Zheng also smiled and rubbed his hands when he heard the words: "Well, you are saturated."
"Hey, I forgot to make the soup." Liu Rui picked up Li Zheng's bowl smoothly, "You either?"
"Don't move, this is Lin Yujing's job!"
Lin Yujing: "Bah Bah Bah!!!"
Li Zheng: "Are you a Hydralisk..."
Du Songtao: "One thing to say, I think the Sporeman is more friendly than the Hydralisk."
Liu Rui: "Or...I'll go to make soup..."
As Liu Rui made soup, Du Songtao also picked up the dinner plate: "Okay, I should go too."
"Oh?" Li Zheng asked, "Don't you come to our group?"
"Stop teasing, I don't look down on you, or I feel that I can't adapt to the 17th Institute, and it's useless to stay." Du Songtao shook his head and pursed his lips. At the end of the Mars launch window in the first quarter of last year, I need to go back and make some preparations. If I lose the chain because of me, I will have to wait another two years next time.
"This reason is convincing." Li Zheng put down his chopsticks and got up and stretched out his right hand. "There is nothing to say about diligence and inspiration. This time I also have luck and inspiration, and you have experienced eight times a night. That kind of effort."
Du Songtao shook his hands with Li Zheng with a smile: "Come on, you still owe me two favors, remember."
Li Zheng smiled and said, "If the Quest for Knowledge can be launched next year, then it will be fine."
"Okay, I hope so." Du Songtao grabbed Li Zheng's hand again, "After the misery, I hope luck will be favored."
"Fortunately, we only favor people who move forward." Li Zheng wanted to let go but couldn't let go, so he had to continue beeping, "Then, next year, when the Qiji launches, goodbye."
"I hope, goodbye." Du Songtao blinked at Lin Yujing by the way, "18 years old is the most delicious season for apples. Don't delay the great time. If you should taste it, try it, otherwise Li Zheng might eat duck. The pear is gone."
"What is it?" Lin Yujing waved her hand in disdain, "For some reason, get up and drive."
Du Songtao smiled, really took a pear out of his pocket and patted it in front of Li Zheng.
"I know you are dumbfounded, but you will thank me in the future."
After that, Du Songtao waved away, hiding his merit and fame deeply.
"What does this mean?" Lin Yujing asked.
"Cold joke." Li Zheng waved his hand, "You still don't know, this person is not far from his old line."
He said that he would eat the pear.
"Beware of spores!"
Maybe it was some instinct. Lin Yujing snatched the pear over and took a picture across the table.
"Ha, I made three bowls of soup."
Liu Rui just returned from making soup, with a bowl on the left and a bowl in the middle. It was not easy to put it on the table.
"Reward you a pear." Lin Yujing pushed Li over without hesitation.
"Ah, I thought that today's fruit has already been taken." Liu Rui sat down and picked up the pear and gnawed.
"My..." Li Zheng was unable to stretch out his hand.
Lin Yujing already bored her head and opened the mobile app: "Can't I buy you an Apple?"
Li Zheng's eyes stared.
Here comes the blessing?
What principle?