Chapter 143 Struggling

Chapter 143 Struggling

In the alchemist's laboratory, the tranquility was amplified into a slightly dull monotony.

Pushing open those two heavy doors, you see a dozen Pentium microcomputers and two workstations running day and night, the low-frequency hum of the cooling fans inside the chassis sounding like some kind of tireless lullaby.

Chen Zhuo sat at a secluded workstation near the door.

This was originally an empty table piled with old peripherals, but Zhang Yuan cleaned it up for him and temporarily added an office chair with casters.

At this moment, Chen Zhuo was looking down at the book "Fundamentals of Aerodynamics" that was spread out on the table.

The book is very thick, with an old-fashioned dark blue cover, and inside it is full of complex partial differential equations and fluid force diagrams.

Zhang Yuan, carrying an enamel mug with the words "Labor is the most glorious" printed on it, walked over from the main control computer while yawning.

He went to the water dispenser, filled a cup with hot water, poured in three packets of Nescafé coffee, and stirred it with an old glass rod.

Zhang Yuan stopped as he passed Chen Zhuo's workstation.

He leaned closer to look at the books on Chen Zhuo's desk, then at Chen Zhuo's gentle and quiet face, and couldn't help but smile.

"Junior brother, isn't this book hypnotic?"

Zhang Yuan blew on the steam rising from the cup.

"When I first started graduate school, I spent two months reading this book, 'Fundamentals,' and I would fall asleep in my dorm every night while reading it. The fluid formulas in it were just too complicated."

Chen Zhuo put down the black ballpoint pen in his hand and looked up.

He glanced at the dark circles under Zhang Yuan's eyes, then at the thick volume in front of him.

"good."

Chen Zhuo leaned back slightly in his chair, his tone gentle.

"The logic is quite sound, but the thickness is a bit lacking. If you use it as a pillow, your neck will easily be unsupported."

Zhang Yuan paused for a moment, then burst out laughing, almost spilling the hot coffee in his hand.

"You little rascal, you look so refined, but you can be quite sharp-tongued when it comes to insulting people."

Zhang Yuan pointed at him with the glass rod.

"This textbook was compiled by some of the most respected fluid mechanics professors in China, and you're complaining that it's too thin?"

Chen Zhuo smiled but didn't reply.

"Alright, see? Don't force yourself. This isn't something you can understand in just a few days. If you get stuck, write it down on paper, and I'll go over it with you over lunch."

After giving his instructions, Zhang Yuan picked up the cup of strong, bitter coffee and returned to the main control computer that was giving him a headache.

Chen Zhuo withdrew his gaze and put his eyes back on the pages of the book.

Zhang Yuan thought he was just putting on a brave face.

Actually not.

Pure mathematics emphasizes absolute rigor and logical consistency; it is about building a perfect castle in the air on a blank sheet of paper.

The mathematics in fluid mechanics is more like wrestling in mud; it requires constantly introducing various rough coefficients, boundary conditions, and empirical formulas to compromise with reality.

He reads very quickly.

It wasn't the kind of speed where he could read ten lines at a glance, but rather because his mathematical foundation was quite good.

The derivation process of the partial differential equations that gave Zhang Yuan and his colleagues a headache back then was as straightforward as seeing one plus one equals two in Chen Zhuo's eyes.

He no longer needs to understand how the formulas are calculated; he only needs to mentally match the physical meanings of these formulas.

On the first Friday afternoon after Chen Zhuo joined the lab, Fang Shi held the project team's weekly meeting as usual.

The meeting room was at the end of the corridor. There was no air conditioning, only two windows open for ventilation.

"Xiao Zhuo, just bring an ear and listen today."

The Taoist priest sat in the main seat and pointed to the very end of the long conference table.

"Don't feel pressured, just consider it as experiencing the actual atmosphere of our research group."

Zhang Yuan even filled a disposable paper cup with warm water and placed it next to Chen Zhuo, treating him like a mascot who had come to listen in.

The atmosphere was tense from the very beginning of the group meeting.

As the progress reports for each sub-project were presented, Zhang Yuan and several other master's and doctoral students responsible for downstream data soon began to argue.

"The basic air pressure data for the front of the car cannot be obtained, and I cannot input parameters into the side flutter model here!"

""

A female senior student with short hair was flipping through a report in her hand, her brows furrowed.

"What can I do if I can't reach the critical point?"

Zhang Yuan grabbed his messy hair, his face full of helplessness.

"The mesh adaptive refinement is already at its maximum. If we cut it any further, the memory of those computers in the lab will overflow, and the motherboards will burn out!"

"But we can't just ignore the peak value of the micro-shock! Once the boundary layer is stripped away, the vortex shelving effect in the wake will be a complete mess, utterly worthless!"

The meeting room was filled with anxiety and a lot of obscure and complicated fluid mechanics terminology.

Chen Zhuo sat quietly at the very end of the long table, without saying a word.

He simply took the black ballpoint pen and wrote down, one by one, the frequently used words and ideas that his seniors used during their arguments on a blank sheet of paper.

The group meeting lasted for more than two hours, but ended without result amidst the sigh of the Taoist priest.

A few more days passed.

The morning passed quickly.

As noon approached, people in the lab gradually got up to go to the cafeteria for lunch.

Chen Zhuo closed the book in his hand and pulled out a piece of draft paper that was tucked between the pages.

Several words were written on the paper in neat handwriting.

Tunnel aerodynamic effects, micro-shock waves, and critical values ​​for piston effect.

This basic textbook in China was compiled in the late 1980s. It talks about fluid data in emerging fields such as high-speed trains in a very general way. In many places, it only gives an extremely vague empirical formula and omits the derivation process.

Chen Zhuo is now very curious to know how the pressure surge curve of the air being violently compressed at the moment when the train head, traveling at a speed of over 200 kilometers per hour, crashes into the tunnel is recorded in the world's most advanced wind tunnel laboratory.

He folded the draft paper in half, put it in his pocket, and followed the crowd downstairs.

When I came out of the cafeteria after eating, the sun outside was scorching hot.

Chen Zhuo didn't go back to his dormitory; instead, he went straight into the old library next door.

After going up to the third floor, I walked to the door of the independent archive room at the east end of the corridor.

The door was ajar.

Chen Zhuo reached out and gently knocked on the door frame twice.

"Enter."

A clean and crisp voice came from inside.

Chen Zhuo pushed open the door.

A burst of powerful, blasting air instantly shut out the stifling heat outside.

The archives room is small, but very clean.

Su Wei was sitting behind the desk by the window, wearing thin black-rimmed glasses, staring at the computer monitor, her hands rapidly typing on the keyboard.

A long string of financial code and probability models that Chen Zhuo couldn't understand were running on the screen.

Hearing footsteps, Su Wei stopped what she was doing and turned around.

"Looking for information?"

Su Wei asked very directly.

"Um."

Chen Zhuo walked over, took out the folded draft paper from his pocket, and placed it on the empty space next to the computer.

Su Wei reached out and took the draft paper, opened it and glanced at it.

"Tunnel aerodynamics, micro-shock waves."

Su Wei read it aloud, her brows twitching slightly.

She looked up and gazed at Chen Zhuo through her glasses.

"These terms are too broad. If I search for these terms directly in IEEE or some core databases of fluid mechanics, I will get at least two or three hundred articles."

Su Wei's tone was very professional, as if she were checking the requirements with a client.

Chen Zhuo stood by the table and thought for a moment.

"Limited to those born after 1995."

Chen Zhuo provided the constraints.

"Focus on finding early wind tunnel test data for the Japanese Shinkansen, as well as relevant models of the German ICE train. For journals, try to select the journal of the American Institute of Aeronautics and Astronautics or the Journal of Fluid Mechanics."

Su Wei nodded, picked up a pencil, and quickly wrote down the supplementary conditions Chen Zhuo had mentioned on the draft paper.

"understood."

Su Wei placed the draft paper next to the keyboard.

Come pick it up after 4 PM.

"Okay, thank you for your help."

Chen Zhuo didn't linger. He turned and left the archives, closing the door behind him.

The whole process took less than two minutes.

There were no small talk, no small chatter, not even a single unnecessary word.

Su Wei looked at the closed door, picked up the draft paper, and placed it flat in front of the keyboard.

She casually saved the financial model running on the screen and skillfully accessed several large foreign language databases purchased by the school.

She didn't need to ask Chen Zhuo, a sophomore, why he was reading cutting-edge literature that doctoral students usually read, nor did she need to ask what these documents were for.

Her job was only to search, filter, and package.

This is what she should have provided.

4:30 PM.

Key Laboratory in Physics Building.

Zhang Yuan had just finished modifying a line of boundary condition code on the main computer and was about to run it when the computer screen unexpectedly froze for a moment.

He sighed irritably, stood up, stretched vigorously, and his bones cracked a few times.

He turned his head to see if the new junior apprentice was dozing off again.

What he saw on Chen Zhuo's workstation was a thick stack of A4 papers, neatly bound together with a stapler.

Paper.

The paper had neat edges and was covered with dense English letters and complex fluid diagrams.

Chen Zhuo was holding a red ballpoint pen, underlining a name on one of the pages, with several lines of derivation formulas written in the blank space next to it.

Zhang Yuan walked over curiously.

"What are you looking at, junior brother? Where did you get this thick stack of English materials? It looks like a brick."

Zhang Yuan walked behind Chen Zhuo and glanced down at the title of the top document.

"Transient Aerodynamic Pressures in High—Speed ​​Train Tunnels"

(Transient aerodynamic pressure inside a high-speed train tunnel).

Zhang Yuan was stunned.

He blinked, thinking he had misread it, then leaned closer to check the journal's source.

Journal of Fluid Mechanics, published last fall.

"you...

'

Zhang Yuan opened his mouth and pointed to the pile of documents in Chen Zhuo's hand.

"Weren't you reading 'Fundamentals of Aerodynamics'? Have you finished that book?"

Chen Zhuo's pen didn't stop; he drew a circle representing the peak pressure on the paper.

"I've finished watching it."

Chen Zhuo said in a calm tone.

"Finished watching?!"

Zhang Yuan's voice rose an octave, attracting the attention of several other people in the lab.

"That book has two volumes, over a thousand pages in total, and you finished reading it in a week?"

"I skimmed through it."

Chen Zhuo put down his pen, turned to look at Zhang Yuan, and his attitude was very frank.

"The basic theoretical framework is not complicated. The main thing is to memorize some empirical constants. However, the chapter on high-speed aerodynamic effects in that book is too old, so I went to the reference room to find some foreign literature from recent years."

Looking at Chen Zhuo's matter-of-fact face, Zhang Yuan suddenly felt that his years of doctoral studies had been a waste.

Did you just skim through it?

That's a nightmare for many fluid mechanics graduate students.

"no..

'

Zhang Yuan pointed to the pile of all-English documents on Chen Zhuo's desk.

"These are papers from the latest few years in a fluid mechanics journal. They contain a lot of obscure and difficult-to-understand terminology, and many sentences are grammatically convoluted. How can you, a sophomore, understand them without any problems?"

Chen Zhuo thought for a moment.

"Some parts are indeed quite difficult."

Zhang Yuan breathed a sigh of relief, thinking that this was more like it, otherwise he would really become a monster.

"Where are you having trouble? Come on, let me translate it for you. I also studied these papers a few months ago. Although I didn't fully understand them, I still grasped the general meaning."

Zhang Yuan pulled up a chair and sat down, adopting the air of a seasoned veteran.

Chen Zhuo pulled out a sheet of paper from the pile and handed it to Zhang Yuan.

"Senior brother, look here."

Chen Zhuo pointed to a derivation process in the middle of the paper.

"When he constructed this model of the surge in stress, he used a set of variants of the Navier-Stokes equations, but from the third to the fourth line, he skipped the expansion of a nonlinear term."

Chen Zhuo pointed to the two lines of equations he had filled in with red pen in the blank space.

"His mathematical range is too large. I reverse-engineered his matrix dimensionality reduction logic based on the initial conditions he gave, and found that he actually made an approximation here, ignoring the slight resistance caused by air viscosity."

Chen Zhuo looked at Zhang Yuan, his tone revealing a pure desire for discussion.

"My question is, in your actual engineering practice, is this kind of mathematically forced omission for the sake of solving equations permissible? What would its error be on the order of magnitude in a real wind tunnel?"

Zhang Yuan looked at the two lines of extremely neat and logically rigorous red pen calculations on the paper.

The expression on his face slowly froze.

He originally thought that Chen Zhuo meant he didn't know the English words or didn't understand the physics concepts when he said he was struggling.

When people say it was difficult, they mean that the original author skipped a step in the mathematical derivation in the top journal article, and he had to manually complete that step himself!

They even went so far as to reverse-engineer the original author's logic and find the compromise between the physical and mathematical models.

Is this what reading academic papers is like?

Zhang Yuan felt his throat was a little dry.

He swallowed hard, looked at Chen Zhuo, and remained silent for a long time.

"What's wrong, Senior Brother?"

Chen Zhuo looked at him with some confusion.

"Is there a problem with the mathematical logic in my derivation?"

"No...nothing's wrong."

Zhang Yuan snapped out of his daze and coughed twice to cover up his embarrassment.

He pointed to the line of equations.

"In actual engineering, the effect of air viscosity on the shock wave surface is very small. In order for the computer to produce results, this approximation is a routine operation. The error is usually controlled within five per thousand, which can be ignored."

Zhang Yuan quickly answered the question, then immediately stood up and picked up his enamel mug.

"Well, you take a look first, keep watching."

Zhang Yuan patted Chen Zhuo on the shoulder, his tone carrying a hint of inexplicable awe.

"Is there anything you don't understand... never mind, you take a look first, I'll go get a glass of water."

Zhang Yuan, holding his cup, almost fled back to his workstation.

He sat in front of the main computer, looking at the line of code that had frozen on the screen, and then turned to look at Chen Zhuo, who was sitting in the corner, quietly deriving a paper from a top-tier English journal on a piece of scrap paper.

Zhang Yuan suddenly realized that what his mentor had said the day he brought Chen Zhuo—that the kid was incredibly quick-witted—was far too conservative.

This guy is definitely not someone who's never been to a lab.

This is clearly a monster that our own mentor dug up from who-knows-where.

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