Chapter 30 One day, solve the problem!
After almost a morning passed, Chang Haonan finally put down the pen in his hand.
On the scratch paper next to it, the mathematical theory and analysis process for nonlinear flutter analysis of the wing are densely listed, as well as the aerodynamic servoelastic modeling method that takes into account aerodynamic control force.
Next, you only need to spend some time modifying the flutter analysis module of MSC.NASTRAN to start simulation calculations.
It was at this time that the door of the laboratory was pushed open again, and a tall figure wearing a dress appeared at the door.
"I just brought you lunch when I came back from the computer room. Come here to get it!"
It was Yao Mengna's voice.
"Thank you Yao Bo!"
"Long live Yao Bo!"
Everyone else in the office rushed to the door as fast as possible, leaving only Fang Zhen and Chang Haonan still there.
"Yao Bo, a new person came to our laboratory today. Didn't you bring him food?" Fang Zhen had a sly smile on his face.
"Newcomer? I don't know who it is?"
Yao Mengna struggled through the crowd and placed a lunch box on Fang Zhen's table.
"It's your senior."
Fang Zhen ignored the lunch box on the table, but pointed at Chang Haonan who just raised his head.
"Senior?" Yao Mengna looked in the direction pointed by the chopsticks in Fang Zhen's hand with a confused look on her face.
Chang Haonan also looked blankly at the two doctors on the other side of the office - he had heard the term "senior" from Fang Zhen the night he first met him, but because he was busy doing experiments, he quickly It was forgotten.
"How...how...how is it you?"
Yao Mengna's cheeks turned pink almost at a speed visible to the naked eye.
At this time, other people who had received their own portions of lunch boxes also returned to their seats, and soon noticed Yao Mengna's strange expression.
"Why is Senior Sister Yao looking at Junior Brother like this?" Xia Tian picked up a piece of green pepper from the lunch box and stuffed it into his mouth, asking curiously.
Chang Haonan curled his lips.
It’s just a junior brother, what the hell is a junior brother...
"Maybe... maybe it's because I met the senior I haven't seen for a long time..." Fang Zhen was laughing so much that he almost fell on the table.
"Ah? Isn't this the junior brother who will be a senior next semester?"
Several other people in the office had gossipy gleams in their eyes.
The first person to react was Xia Tian. After all, she had dinner with Yao Mengna and Fang Zhen that day.
"Oh, he's the one..."
Xia Tian covered his mouth with one hand and didn't even notice that the potato slices he had just picked up fell off.
That very effective simulation idea was actually told to Yao Mengna by this junior fellow who was only in his junior year!
"Junior sister Xia Tian, what's going on?"
Everyone's eyes turned to Xia Tian.
"summer!"
Yao Mengna raised her eyebrows and clenched her fist fiercely into the air in front of her.
Xia Tian, who was about to open his mouth to explain, shrank his head and retreated instantly.
However, as the senior brother, Fang Zhen was "not afraid of power" after all and told the whole story.
When he finished speaking, Yao Mengna had already leaned back on her desk to pretend to be an ostrich, and did not raise her head no matter how she screamed.
The society is dead.
All in all, I regret it.
Very sorry.
It was just a casual comment at the time.
Who would have thought that he would become a junior fellow student in the same laboratory...
When she thought that she would be classmates with him for at least three years in the future, Yao Mengna felt that the whole world had become gloomy.
"Don't be like this, don't be like this." Chang Haonan really didn't expect that Yao Mengna would give herself such a title: "I shouldn't be that old."
After saying that, I couldn't help but laugh.
"I ate a lot for breakfast, and I'm not hungry yet. Junior brother, just eat my share."
Fang Zhen, who had finally laughed enough, stood up and placed the unopened lunch box on his table in front of Chang Haonan.
This also allowed him to see the dozen or so pieces of draft paper scattered on Chang Haonan's table. .
"Huh?" Fang Zhen's expression suddenly turned serious:
"This is... Lagrangian-Green strain, and... Kirchhoff stress tensor... Are you going to rewrite the dynamic equations of the wing structure under nonlinear conditions?"
"Senior brother is awesome, you can tell at a glance." Chang Haonan put down the pencil in his hand, and then gathered the spread out draft paper.
When Fang Zhen heard this compliment, he was a little smug at first, but then he immediately realized it - if he understood it, he was very powerful, so wouldn't Chang Haonan himself, who derived the equation, be even more awesome?
Who are you praising in this sentence?
"Ahem - let's not talk about this for now, where are you going?"
"Forget it." Chang Haonan organized the draft paper and put it aside, and then opened the lunch box on the table, with the same expression on his face.
The short answer and the flat tone seemed to be talking about a trivial matter.
But Fang Zhen knew what this junior brother was doing in the morning, so after hearing these three words, his whole body was immediately excited.
"Finished?" Fang Zhen reached out to the pieces of draft paper with almost trembling hands: "Can I take a look?"
"Just take a look." Chang Haonan was concentrating on cooking and replied without raising his head.
About twenty minutes later, Fang Zhen was still standing there like a sculpture, but his expression had changed from the relaxed and carefree expression at the beginning to a frown.
Not only is the mathematical knowledge involved in the later content more profound, but more importantly...
Chang Haonan must have entered a state, so when it came to the last few pages, the handwriting on them was really a bit dramatic.
"Senior Brother Fang Zhen, what are you looking at so seriously?"
At this time, everyone had finished eating and was about to enter lunch break, but Fang Zhen standing behind Chang Haonan looked extremely eye-catching.
"Our junior has derived the generalized aeroelastic equation under nonlinear flutter conditions..."
Although there were two pages of content that he didn't quite understand, Fang Zhen still understood the final conclusion.
Chang Haonan was eating his rice when he heard Fang Zhen's words, but he still took the time to add:
“Not only that, but also the aeroservoelastic system state space equations that take into account the wing control surfaces, so that the effect of the flaperons can be taken into account in the wing modeling.”
These two sentences made the entire laboratory fall into silence for an instant.
Even Yao Mengna, who had been pretending to be an ostrich just now, raised her head, and even the flush on her face faded a lot.
They certainly know what the generalized aeroelastic equation means.
As long as this equation is solved and then processed very simply, the critical speed of nonlinear flutter of the wing can be obtained.
As for the equation Chang Haonan mentioned later, not many people care about it.
It’s not that everyone doesn’t understand, but at this time, active flutter suppression is not yet an obvious science, so introducing movable control surfaces into wing modeling seems to be a thankless task.
But actually, that was the focus of his morning's work!
Thanks to book friend [Lost Pigeon] for the 2000 starting coin reward
