179: Chapter 179 Listening to Lectures

During the waiting period leading up to the Navier-Stokes Equation report, Chen Youhua spent most of his time at Z University, ready to handle any urgent requests or meetings that might arise from Dean Tang.

After finishing the daily tasks at the A-705 Laboratory, he would occasionally feel a rare moment of leisure and... a bit of boredom.

That afternoon, Chen Youhua strolled past classroom after classroom, from which came the teachers' lectures, some passionate and others calm.

"It seems like it's been a long time since I've attended a class, hasn't it?"

Chen Youhua watched the students in the middle of their lessons and fell into memories.

Since starting university, he had attended very few classes, mostly self-studying in the library, and had almost forgotten what it was like to attend a lecture.

Although self-study allowed one to master knowledge quickly, being able to listen to a lecture in the same classroom with classmates—wasn't that a kind of youth?

Chen Youhua, intending to reminisce about his youth, pushed open the back door of a large lecture hall, slipped in quietly, and found an empty seat in the last row.

This was a large class for "College Physics (Part II)," and the students sitting below were sophomores.

The lecturer was a man in his forties with a serious expression, his handwriting on the board neat and his logic clear.

Chen Youhua began to listen with great interest.

The teacher was explaining the basics of fluid mechanics, content he already knew by heart, but he was intrigued by how the teacher broke down these complex physical concepts into steps that students could understand.

How to emphasize key points, explain difficulties, and guide students to build a physical mental image rather than just rote-memorizing formulas... this feeling was very novel.

This was the perspective of an educator, which was completely different from his own perspective as a researcher pursuing extreme depth and breadth.

He understood that basic education required first building a knowledge framework that might be simplified but was structurally complete, rather than falling into a bottomless abyss of details from the start.

True deepening was left for those graduate students who would choose to continue climbing in the future.

For someone like him who had long since formed a complete and detailed network of knowledge, such a perspective was very novel.

Just as he was immersed in this feeling of reviewing the old to learn the new.

The phone in his pocket began to vibrate continuously, the buzzing sound appearing somewhat abrupt in the relatively quiet classroom.

He frowned slightly and took out his phone to see a barrage of messages from his cousin, Chen Xinran.

"Cousin, Cousin! I'm on monthly break! Hehehe, finally free!"

Attached was a cat emoji rolling around in happiness.

"We have monthly exams before every break, it's so tiring, who gets it!"

"Cousin, are you in ZJ? Can I come visit you?"

"Cousin, Cousin, what are you doing? Why aren't you replying to my messages?"

"Wuwuwu, Cousin, I finally got a break. You aren't at Z University, are you? I want to come find you..."

Chen Youhua sighed helplessly.

This little cousin was lively and clingy, but as her older brother, he really couldn't feel any genuine annoyance toward this enthusiasm.

His fingers tapped a reply on the screen quickly.

"I'm back in ZJ. I'm in class. I'll talk to you later."

The message was replied to almost instantly.

"Oh oh, okay, Cousin! Cousin, why are you still attending class? Didn't you graduate? Do you still need to take classes?"

Chen Youhua looked at this line of text, unable to laugh or cry.

He looked up at the podium; the teacher was writing on the board with his back to the students, seemingly unaware of the movement in the back row.

He quickly lowered his head to reply.

"Can't I study a bit? I also need to keep making progress, you know. Aren't you going home for your monthly break? You're studying at HZ High School? That shouldn't be far. We'll talk after I finish class."

After sending the message, he had just stuffed his phone back into his pocket and was preparing to continue listening to the lecture when he suddenly felt something was wrong.

The classroom was too quiet.

He looked up, his heart skipping a beat.

He saw that the teacher on the podium had turned around at some point, his hands supporting himself on the podium, his gaze like a torch, locked precisely in his direction.

The entire class of over a hundred students also turned their heads in unison, following the teacher's gaze, looking at him sitting in the last row wearing large sunglasses.

The atmosphere instantly dropped to freezing point.

Teacher Wang on the podium pushed up his glasses, his tone calm but carrying authority.

"The last row, that student wearing sunglasses, yes, you. It seems you have already mastered the content of this lesson very thoroughly and don't need to listen to me, right?"

Chen Youhua secretly thought this was bad, but he had no choice but to bite the bullet and stand up.

Teacher Wang pointed his laser pointer at the projection screen, where there was an extracurricular extension question he had just assigned, aimed at broadening the students' thinking, with a difficulty far exceeding the basic content of the textbook.

"Consider the steady flow of an incompressible viscous fluid in a complex three-dimensional microtubule network. It is known that the pipe wall satisfies a certain specific slip boundary condition, and the fluid is driven by a pressure gradient that oscillates periodically with time. Please briefly discuss the core control equations, key dimensionless parameters, and the main mathematical challenges that might be encountered in analyzing this flow problem."

For a sophomore, this question was hell-level difficulty, involving multiple concepts beyond the curriculum such as viscous fluids, complex boundaries, and unsteady flow, which they hadn't learned yet.

However, for Chen Youhua, this was almost equivalent to asking him what one plus one equals.

He didn't even intend to walk up to the podium to write it down; he just stood where he was, organized his thoughts slightly, and spoke clearly and fluently.

"To analyze this problem, one must first start from the most fundamental conservation of mass and conservation of momentum, namely the continuity equation for incompressible fluids ∇·u = 0 and the Navier-Stokes Equations ρ(∂u/∂t + (u·∇)u) = -∇p + μ∇²u + f. Since it is driven by periodic oscillation, the pressure gradient term should be expressed as a periodic function of time."

His speaking pace was steady, without any hesitation.

"The key lies in handling the Navier slip boundary condition, that is, at the wall, the fluid tangential velocity is proportional to the tangential stress, which introduces additional boundary parameters... Secondly, it is necessary to perform non-dimensionalization; the key dimensionless numbers introduced include the Reynolds number, representing the ratio of inertial forces to viscous forces; the Strouhal number, representing unsteady effects; and the slip number defined by the slip length and characteristic length... Furthermore, in such a complex microtubule network, geometric nonlinearity and flow separation phenomena will be very significant..."

He continued to delve deeper, pointing out the mathematical tools and theoretical difficulties required to solve such problems...

He spoke for a full three minutes, with rigorous logic, precise terminology, and a progressive structure, clearing up the analysis framework of a complex problem with complete clarity.

The students below, who were initially watching for fun, gradually became dumbfounded.

"Holy crap... who is this guy... he sounds so badass..."

"Wait, what was that long string of things he said? I totally don't understand, are we studying the same book?"

"Who am I? Where am I? I recognize every word he said, but put together, I don't understand a single sentence!"

"This is definitely not someone from our class! If we had such a genius in our classes, I would have known about it long ago!"

"Three minutes! I want to know all the information about this person. I don't allow anyone more awesome than me to exist in this school."

The students whispered to each other, their eyes filled with confusion, shock, and a hint of admiration.

Everyone thought it was a genius from another major who had come to audit the class.

Teacher Wang's serious expression on the podium also softened. He listened carefully to Chen Youhua's discussion, a flash of surprise and appreciation crossing his eyes.

He pushed up his glasses and nodded.

"Hmm... this student explained it very well. The logic is clear, the theoretical foundation is very solid, and the understanding of the problem is also very profound."

The tone shifted, and his voice took on a hint of admonition again.

"However! You still need to listen to the class carefully. Also, wearing sunglasses in class, what is that supposed to mean? Do you have an issue with the teacher, or do you think the classroom light is too dazzling? Take off the sunglasses and listen to the lecture properly."

Now Chen Youhua was really a bit hesitant.

Once the sunglasses were off, everyone would know who he was. How was he supposed to maintain his low-profile image?

But the teacher had said this much and was clearly giving him a way out; if he didn't take it off, it would be disrespectful to the class and the teacher.

He helplessly, under the gaze of the whole class, slowly took off those large sunglasses.

When his face was completely exposed under the classroom lights, the air seemed to freeze for a second.

Immediately, the whispers turned into low gasps, and then spread rapidly like ripples!

"Holy crap! Look! Who is that!"

"Holy crap!! Holy crap!! It's Chen Youhua!!"

"Oh my god! It's really him! How is he here?!"

"I was actually listening to Chen Youhua explain a problem just now?! I thought it was some monster, phew~ that almost shattered my Dao heart."

"Alive! It's a living Chen Youhua! So close to me! Take a picture! Quick!"

"I knew the voice sounded familiar! I've heard it on the news!"

In an instant, the entire classroom was plunged into a commotion.

Almost all the students took out their phones and secretly took pictures of the back row. The students in the back row couldn't even help but turn around to get a better look.

Teacher Wang on the podium clearly recognized Chen Youhua completely.

The expression on his face instantly changed from serious admonition to astonishment, followed by a hint of imperceptible embarrassment and nervousness.

He had originally thought it was just a relatively outstanding student; he hadn't expected a true deity to have arrived.

You might think Chen Youhua is an unreachable big shot in the student circle. In reality, in the circle of professors and teachers, Chen Youhua is even more of a god-like existence.

Because they understand the actual difficulty of the problems Chen Youhua has solved better.

Teacher Wang quickly cleared his throat, his tone instantly becoming incomparably polite, even adding honorifics.

"Uh... so it's Professor Chen... You also came... to attend the class? Welcome, welcome..."

Chen Youhua could only smile awkwardly but politely, nodded, and quickly sat down.

"Ahem! Quiet! Quiet! Everyone, be quiet!"

Teacher Wang tapped the podium, trying to restore order in the class, but his voice was obviously much softer than before.

"We... let's continue with the class..."