Chapter 301: Reproduce

After lunch, some people stayed at the proving ground to finish up, and the main team drove back to the headquarters.
Naturally, Li Zheng rubbed onto the familiar little white car of Aunt Shen.
Lin Yuejing took a seat on the co-pilot and turned his head back as soon as he wore his seat belt. He yelled with a grin: "Enough consciousness."
Li Zheng also learned her look and grinned, "Hey, what's the matter with Aunt Shen?"
"Mom!" Lin Yujing turned around and listened to Lan, "You see he has a thick skin."
"This... I actually eat this one." Shen Tinglan smiled, and then started the car to go out in a wheel. "Okay, don't tease you, Li Zheng is back, It's time to talk about business."
The two quickly put away their clamoring emotions and listened honestly.
"I have asked the secretary, and to let you participate further in the work, a lot of technical content should be open to you."
"But after opening up, it means that it is more difficult for you to go abroad."
"Considering these, I suggest you put your work aside for the time being, prepare for IPHO, and wait until the end of IPHO in November before contacting these contents, how?"
"It's all done, don't go." Lin Yujing answered, "I made this clear when I interviewed."
Li Zheng also nodded: "Well, I just have to ask someone to return the medal to the old man."
"So simple?" Shen Tinglan was slightly surprised. "I thought you were a man with a strong sense of purpose, Li Zheng."
"Once there is a more ambitious big goal, there is no obsession with the previous small goal." Li Zheng shook his head and smiled, "doing 1% of the power for Huang Er's success, which weighs more than 100 international gold medals."
"Ah, this goal is really strong..." Shen Tinglan glanced at Lin Yuejing, "What about you, does it matter?"
"Examination is only a means, not an end." Lin Yuejing shook his head, "Now that the goal has been achieved, whether it is Huang Er or the astronomy department already, I can't wait to not take the exam again in my life."
"This is your own decision, don't regret it." Shen Tinglan said quite rightly.
Lin Yuejing urged: "Hurry up and talk, wait for the core cause of the failure for a long time."
Li Zheng smiled and said, "I will not regret it. Now I have lost interest in all competitions."
Shen Tinglan immediately asked: "But you went to the biology exam this morning."
"Ah... this, I like biology." Li Zheng had to say something very disgusting for [Five Sons to enter the school].
"Okay, don't be nervous." Shen Tinglan smiled. "It's only half a day off. I'm not Chen Hongbing. You will be free in the future."
"Sure enough, he followed the right person." Li Zheng threw a punch in excitement.
"It's my light." Lin Yuejing yelled and punched.
"How did it start again." Shen Tinglan asked, "Do you still want to hear the cause of the failure?"
"Listen!" The two spoke in unison.
Next, Shen Tinglan reproduced the launch center on August 8th for them, an unknown night.
...
On August 8, 2019, Wenhai Aerospace Launch Site, Command Center.
20 o'clock, 07 minutes, 00 seconds.
"ignition!"
With the order of the messenger, a thin red line appeared at the tail of the rocket.
Then, the red line burst suddenly, like a little sun turned out.
But Shen Tinglan, who is sitting in the front row of the command center, is very clear that this is actually 5 little suns.
At the center is the core-grade YF-86 engine of the main body of the rocket. A huge amount of oxyhydrogen fuel is injected into the combustion chamber by two turbo pumps. Within only 1 second, 100 atmospheres were reached. During the combustion, the temperature of liquid hydrogen rises instantly from -253 degrees to over 2000 degrees.
In the next 500 seconds, this engine will remain in this state, consuming all fuel, and then detached from the main body of the rocket, and the core secondary engine above it will continue to complete the mission.
The four little suns around are Huang Er's four boosters.
Each of these four boosters is equipped with two 120-ton YF-90 kerosene engines. Compared with the core rocket, these four guys are the real Big Macs. They will take off the most difficult 300 seconds on the rocket. The inside was burned wildly, supporting more than 90% of the takeoff thrust for Huang Er.
They were like two hands of parents, burned themselves out at any cost, only to support the dream of Huang Er, a child, and then let go of their hands, no longer adding a kilogram burden to the child.
Looking at the little sun in the picture, Shen Tinglan grabbed his hand and meditated in his heart.
Fly, fly.
Xiao Huang Er, try to fly upward.
Not only her but everyone in the command center seemed to be meditating.
No one speaks, everyone is welded to their posts like nails, and there are only screens and data in front of them, hundreds of thousands of hardening data.
They seemed to be staring at a newborn baby, and even a faint cough would make them nervous.
They seemed to be staring at a dying old man, only wishing he could survive this last 2000 seconds.
In this silence, every 10 seconds of "tracking normal" broadcast, it seems to be the sound of the "didi" of the electrocardiogram. Although it is only boring and repeated, it is the voice that everyone wants to hear most.
This broadcast is like a basic rhythm, with Shen Tinglan sweeping the core data on the main monitoring screen once every 10 seconds.
As long as it is done about 200 times like this, everything is done.
But just at the 18th time, a change appeared.
The core level is composed of two YF-86 engines, and the instantaneous thrust of one of the extensions has been reduced from 518KN to 506KN.
This is a small change, like a baby's cough.
But Shen Tinglan knew that the baby would not cough at this moment.
At this stage, as the height increases, the air becomes thinner and the resistance gradually decreases. The instantaneous thrust of the oxyhydrogen engine should be increased at a slow speed, and there should not be a significant decrease.
Just like the second extension, its thrust is still maintained at a high of 522KN.
Of course, this may only be a short period of uneven combustion, or a small gap in the instantaneous fuel injection density. After all, drinking mineral water sometimes takes a bite and a bite. Physics will occasionally make such a joke.
But Shen Tinglan's eyes were still fixed on this data.
After 10 seconds, the data is refreshed.
【Core level A thrust: 506→214】
【Core level B thrust: 522→529】
Shen Tinglan suffocated.
Without any gradual preparation, cut directly.
The alarm sounded, and the monitor tried to expand the report with a steady voice: "It was detected that the thrust of the extension of the core-level engine has dropped significantly."
It was Chen Hongbing who was suffocating with Shen Tinglan.
But Chen Hongbing's breathing only stopped for three seconds.
He has previewed various situations, which is not the worst.
"Ballistic group." Chen Hongbing said to the microphone, "At this stage, if the core level one is separated in advance, can the core two core three redundant fuel successfully push the satellite into orbit."
"After calculations, the core level 1 still needs to persist for 70 seconds in the current state, and the core second core three can complete the task."
The engineers of the ballistic group responded almost instantaneously, which shows that they started the software calculation long before Chen Hongbing asked.
As soon as the voice fell, new data came.
【Core thrust: 214→37】
Almost at the moment when the data appeared, Chen Hongbing spoke again: "Ballistic group, recalculate."
After 5 seconds.
"Report, with the current arrow status, Huang Er will not be able to enter the established track."
The scene was silent again.
【Core level thrust: 37→6】
"Report, the core-level engine...an extension...has...stopped."
This time, the monitor has been unable to maintain a stable mood.
Even Shen Tinglan found that she was just a fragile little girl. Faced with this situation, she could not say a word and her brain was blank.
Chen Hongbing asked again: "Forcibly separating, can the satellite be put into low orbit."
"It is reported that with the current arrow conditions, the rocket cannot reach the speed of the first universe."
【Core level thrust: 8→null】
"Ballistic analysis of existing monitoring." Chen Hongbing ordered.
This time I waited a long time, but it didn't look like a dozen seconds.
"Huang Er has deviated from the planned trajectory due to the stand-alone shutdown of the first extension. If the situation remains unchanged, the arrow body will accelerate into the East Pacific under the separate thrust of the second extension."
This time, Chen Hongbing did not speak immediately, but after a few seconds of entanglement, he looked heavily at Zhao Zhenhua beside him.
Zhao Zhenhua's expression did not change much, but his eyes were red.
"Prepare to salvage with all your strength."
"Yes." Chen Hongbing ordered this, "The launch failed and all the engines were turned off urgently to let the arrow body fall into the nearer waters. Emergency contact the Ocean Bureau and Meteorological Bureau. Do your best to salvage."
At this moment, everyone seemed to be taken out.
The baby failed to survive.
The old man failed to hold up.
Before getting up, Chen Hongbing took the back of Shen Tinglan's hand and shook it heavily.
"I can't hold it, there are many people who can replace me."
"But no one can replace you."
"Don't resign, don't evade."
"I top."
...
Inside the car, Shen Tinglan's eyes flashed wet.
Even if it has been so long in the past, that night was still enough to elicit the pain of her life.
"Well..." Lin Yujing's hand gently rested on his mother's arm. "It's hard... mother."
It was still so long since Shen Tinglan first told her about that night.
Li Zheng is certainly painful, but this does not affect his basic analysis.
"It takes about 30 seconds from the occurrence of an omen to a complete shutdown. Although the process is fast, it is still a linear process."
"There is no change in appearance, no explosion, no fuel leakage, no damage to the combustion chamber, and no early contact in the pre-combustion chamber, which has ruled out many failures."
"Under this premise, the thrust continues to decline... that can only be caused by problems with fuel injection." Li Zheng said with a nod. "Well, this matches the parameters given by the algorithm."
"You really didn't do anything in the test group during this time." Shen Tinglan wiped his eyes and gradually regained his calm emotions. "In the 86 design, liquid hydrogen and liquid oxygen are stored separately. Turbo pump and oxygen turbo pump, injection into the combustion chamber, my first reaction is also a problem with one of the pumps. From an empirical point of view, oxygen pumps are more likely to have problems because they are naturally subject to strong oxidizing environments. It is also the basis of our first failure model."
"But... this kind of problem hasn't happened on the ground test for a long time." Lin Yuejing said unwillingly, "And the core level has two engines. Under the same environment, the other one is not too good." of."
"If the Ocean Bureau can salvage Huang Er, you will probably have answers to your questions." Shen Tinglan sighed, "But now, we have answered them based on simulation. The force and heat after the rocket takes off is extremely complicated. There is a vibration problem that is a headache for everyone. Our test drive is impossible to simulate all environments, so we can only explain that when the rocket engine is lifted for about 180 seconds, the force and heat environment of the rocket engine has reached a test. The severe conditions that could not be simulated led to abnormalities in the local structure of the turbine unit, and the fuel could not be injected into the combustion chamber."
"This can only be done..." Li Zheng also sighed his head, "How good it is to be able to salvage... I know it as soon as I tear it down... But the positioning is really difficult... I don't know if it will be caught there by the waves. "
"It's also not possible that Magri was the first to sneak away." Lin Yuejing shouted again, "bad!"
"Okay, don't conspiracy theory." Shen Tinglan played a round, the car has been driven back to the first hospital, "Zeroing can be so smooth, you and the eleventh gave the diagnosis of the contribution, based on the test results, we The fault point has been locked on the oxygen turbopump. Under a special environment, the shaft system will indeed crack or even break. You know that for the pursuit of greater thrust and specific impulse, the pressure of the combustion chamber is For a pressure of more than one hundred atmospheres, to inject fuel, the speed of the turbine and the pressure of the pre-combustion chamber must be greater, coupled with the low temperature environment and strong oxidation, this turbo pump can be said to be among the difficulties in aerospace engineering difficulty."
At this point, Shen Tinglan stopped the car, turned sideways and said seriously.
"If aerospace engineering is a test paper used to test a country's cutting-edge industrial strength, then this pump is the ultimate question of the test paper."
"Well!" Lin Yuejing heard more and more, "The heaviest gem in the aerospace crown!"
Li Zheng, however, thumped Xia Lin's chair extremely reluctantly: "So is it actually a craft issue... or is it a material science issue?"
"No, no, just complaining about craftsmanship and materials is the biggest misunderstanding of engineering." Shen Tinglan was not in a hurry to get off the bus and explained on the spot, "Engineering is a whole, our work is under the existing process and conditions Use our knowledge and mind to design a rocket that can be successfully lifted off. In the face of failure, don’t push the blame to the process and materials. They are all strictly tested when they leave the factory and meet our engineering standards. Of course, in breakthrough projects, we still have the right to demand more advanced craftsmanship and better materials, but don’t push the blame on them. After all, there are no indestructible steel plates in the world. Even if there are, we should also use I'm sorry."
"Ah..." Li Zheng sighed, "I'm narrow... Teacher Shen is right, the cook should not complain about the ingredients."
"Chef..." Shen Tinglan froze for a moment, then couldn't help laughing. "It turns out that the engineer can be compared to a cook... I also learned."
"If nothing else, Li Zheng's fish steak is delicious." Lin Yujing may have thought of the gourmet experience, and unexpectedly said good things, "Let's let him do it for you."
"After two days, wait for zero to finish, I invite you to dinner." Shen Tinglan said with a car key, "At this time, the Sixth Yard will pay close attention to improving the oxygen pump part of the engine. The structure is further optimized, and it is best to further strengthen the vibration suppression."
"Shock?" Li Zheng asked.
"Ah, you haven't learned this yet. Go upstairs and teach." Shen Tinglan stretched his waist, which was a good mood. "The Rockets mostly broke through the air resistance at super high speed during this process. The vibration generated in the process will affect the operation of each component of the rocket. It can be said that it is the first enemy of the rocket. One of our design difficulties is to combat vibration and better protect the operating environment of each part. Now know Why are you recruiting mechanics?"
"It turns out so." Li Zheng followed Shen Tinglan and got off the bus. "It's too foolish to call the teacher, I'll call you the teacher directly!"
"Ah..." Shen Tinglan was shocked again, "This..."
"Give me the'master'!" Chen Hongbing suddenly appeared with a big swing. "How many times have you said it, just call Mom, how are you going to talk blindly here."
This time, Shen Tinglan was used to it and did not run away: "Go, leave us alone."
"Don't don't, you have to come." Chen Hongbing waved, "You have a summary meeting with the Sixth Academy, you have to come."
"Well." Shen Tinglan responded and handed the office key to Lin Yujing. "Go to my office first and quietly give Li Zheng the recent study materials. Study hard and don't fight."
"Oh."
"Yes."
After the two left, Chen Hongbing laughed and said, "How can it look like a summer vacation care class... Don't fight? Dry firewood in your office, is that a fight?"
"Ah." Shen Tinglan also covered her mouth and quickly pulled out her mobile phone. "If there is a monitor...I have to tell them..."
"Ah, let's go." Chen Hongbing waved his hand and leaned into Shen Tinglan's ear and whispered, "You are not curious about what they are doing together? Rest assured, I will take care of this matter, and I will accompany you to watch the surveillance ."
"!" Shen Tinglan was surprised first, and then retreated, "You don't often watch my office monitoring?"
"I'm idle!" Chen Hongbing waved his hand cursingly. "Anyway, I really think it's monitoring work."
"It's terrible, I will transfer away after the Huang Er project..."
"Hey hey, don't watch, don't watch, kidding."