"Thirty meters below us, there is a pump-jet thruster. My job is to improve its operating noise, enhance its energy efficiency, and enhance its reliability..." Pan Guoxiang introduced, "We are doing preliminary work here.

After testing, if it passes the early experiments, it will be taken to the drag pool and water cave for more complex follow-up research..."

"Because my work involves some secrets, I won't show you the relevant information and models..." Pan Guoxiang looked at Gu Xiaobai's curious face and cut him off mercilessly, "But Xiaobai

You should understand that my work is very important, so I have no time and no way to cooperate with you."

Next to him, the director accompanying the tour glared at him, "Can you speak?"

Your job is important, but other people’s jobs are not?

Of course, there is actually a chain of contempt in the scientific community, but the chain of contempt in the scientific community is not very regular.

Many people feel deep down that their own work is important and other people's work is shit.

For example, Pan Guoxiang thinks this way about Gu Xiaobai now.

Of course, for the director, research that can satisfy his needs is important research.

Now the landlords don’t have any surplus food, so it’s hard to find funds.

Gu Xiaobai said: "Can you open it and let me have a look?"

"This is okay." Before Pan Guoxiang could say anything, the director waved his hand.

The propeller was hidden 30 meters underwater and could not be seen or even heard. This was why they did not care about Gu Xiaobai coming to visit.

After all, Gu Xiaobai is not just a cat or a dog, he is also a top expert in the field of acoustic subdivision. Although his work is confidential, communication within the industry is also necessary, otherwise it will be done behind closed doors.

A student next to him immediately ran away. After a while, the water surface began to fluctuate slightly.

The 30 meters of water basically covered up all the sounds, and only the slight sound of water could be heard echoing.

Gu Xiaobai lowered his head, looked down carefully, and listened.

Seeing his serious attitude, Pan Guoxiang felt a little funny.

With such a long distance and a 30-meter-thick layer of water, it’s amazing what you can hear!

Moreover, many of the noises generated by these underwater propellers are infrasound and ultrasonic waves, which far exceed the limit of human hearing and are impossible for human ears to hear.

He said to Gu Xiaobai: "This is the work we are doing, which belongs to the categories of fluid mechanics and hydroacoustics. Xiaobai, you are studying musical instrument acoustics and atmospheric acoustics. Have you done any research on fluid mechanics and hydroacoustics? My personal suggestion is,

Newbie, you still need to learn some knowledge of fluid mechanics. I personally think that acoustics is a subset of fluid mechanics. In the physical process studied by fluid mechanics, there is the exchange of energy, transmission, and the exchange of mass, but it mainly focuses on

The study of mass. In the physical process of acoustic research, there is only the transfer and exchange of energy, not the exchange of mass. It focuses on the study of acoustic energy fields. The theories of the two disciplines have certain similarities. Generally speaking, fluids are used

The theory of mechanics can also solve certain acoustic problems, so if you want to make achievements in acoustics, Xiaobai, you must also learn fluid mechanics. Why not become my graduate student..."

The more Pan Guoxiang talked, the happier he became, and he seemed to be giving advice, but the expression on the face of the director next to him became more and more ugly.

What do you mean, saying that other people’s acoustics is a subset of your fluid mechanics? Is this belittling other people’s acoustic research? And when you ask others to be your graduate students, you really don’t treat them as equal scholars, but treat others as students.

see?

Gu Xiaobai nodded and said: "Yes, fluid mechanics and acoustics are related. Fluid mechanics is a branch of mechanics, and acoustics is one of the five basic disciplines of physics: mechanics, thermal science, acoustics, optics, and electricity. In this respect,

It can be said that acoustics is the uncle of fluid mechanics..."

Pan Guoxiang's face turned dark with a "brush".

Who do you think is the uncle?

Boy, I think you want to rebel?

"Your statement is wrong. Acoustics should definitely be subject to fluid mechanics. Although acoustics is its own system in solving specific problems, it is nothing more than simplifying basic equations and more concrete descriptions, using mathematical tools

It’s all the same, you should try to use fluid mechanics, solid mechanics and fluid-structure coupling to do acoustics, so that you can..."

Next to him, Pan Guoxiang's students raised their foreheads with their hands. Did the teacher have a quarrel with Xiaobai?

Why can the teacher quarrel with anyone?

Teacher, please look up and take a look at Xiaobai’s handsome face! How can you bear to quarrel with Xiaobai!

Wait, did the teacher secretly take off his glasses?

With this high degree of myopia, are you facing a blurry luminous body talking about it now? Otherwise, how can you have enough courage?

"Teacher Pan, you are right. Fluid mechanics and acoustics do have many aspects in common, but this cannot be changed. In fact, many aspects of fluid mechanics come from acoustic research... But what you said is that fluid mechanics is used to solve acoustic problems.

I think the idea is feasible and I can try it.”

With that said, Gu Xiaobai closed his eyes.

At that moment, the flow of time around him seemed to have stopped for an instant.

Gu Xiaobai's consciousness entered his memory palace, and time was slowed down countless times. In the huge "music room" that looked like a factory, smoke filled the air, and endless streams of light flickered, and Gu Xiaobai slowly emerged from it.

The huge factory-style laboratory where Xiaobai is at this moment.

Tall metal supports, deep pool water...

Everything is just like the outside world.

The "mv system" provided by the system to Gu Xiaobai is actually the most powerful simulator in the world.

It can completely record and intercept a period of real time and space.

Gu Xiaobai stretched out his hand and gently moved it upward, as if there was an invisible big hand that moved the space instantly.

The next second, Gu Xiaobai sank into the water. In front of him, a huge, rapidly rotating pump-jet thruster appeared.

Gu Xiaobai gently put his hands together, and the propeller and the pool instantly shrank, turning into a plaything in Gu Xiaobai's palm, similar to a wave machine in a fish tank.

Gu Xiaobai observed this for a while, then pulled his hands outward, and the propeller was enlarged to infinity. In front of Gu Xiaobai, there were tiny cavitations produced by the tip of the propeller blades, which were generated and then burst...

The slowly rotating propeller is like a huge black hole that can suck in the entire earth.

Behind the black hole, a dark mass was staring at Gu Xiaobai unhappily.

This system gives you an MV system. If you don’t shoot MVs, you can use it to study physics all day long!

How much monthly ticket does physics give you? Why do you do this?

Gu Xiaobai was a little embarrassed to be stared at by the system like this, and said with a smile: "Well, actually I am studying musical instruments..."

"You can think of this big rotating propeller as a huge musical instrument that can be used in the water. Now we want to make its sound as small as possible and reduce the noise..."

The system stared at Gu Xiaobai, bah, I don't study well, don't lie to me!

"That's it anyway..." Gu Xiaobai spread his hands, "You can't help it if you don't believe it..."

The water flow passed through the pump jet propeller, sprayed on Gu Xiaobai's body, then passed through his body and flowed behind Gu Xiaobai.

Gu Xiaobai's body seemed to be semi-solid in this space, and every part of his skin could feel the changes in the water flow.

Humans cannot hear ultrasonic and infrasound waves, but this does not mean that humans cannot feel the pressure changes they bring.

And now, Gu Xiaobai has obviously turned his body into this kind of receptor.

Gu Xiaobai's consciousness was actually completely connected to this space. At this time, under his control, the water flow turned into threads with different colors, but never intertwined with each other, and passed through Gu Xiaobai's body.

But the sound turned into countless transparent arrows of different thicknesses, radiating in all directions.

He stretched out his hand, and the paddle gently changed with his fingers, length, width, shape, thickness...

The threads and arrows are also constantly changing.

And for a moment, it seemed that all the noise had been offset and suppressed. Under the noise floor reduced to a very low level, a constant sound wave came.

"Huh?" Gu Xiaobai's eyes lit up.

He controlled the blades to slowly change, and the pitch also slowly changed.

Next to him, the dark Xiao Hei looked confused. Is this really a musical instrument?

It seems quite fun.

Sure enough, I knew that my host could not be so ruthless and use my system to study physics!

Gu Xiaobai opened his eyes, and several people around him looked at him in confusion, wondering why he suddenly closed his eyes.

"Do you have CFD software?" Gu Xiaobai asked a student next to him.

"Of course." How could someone who studies fluid mechanics not have cfd software?

"Then you guys try this later." Gu Xiaobai took out a pen and paper and started writing.

A long formula, followed by a long list of parameters.

"Thank you for letting me visit. It's time for me to go back and prepare for the tour." Gu Xiaobai bowed to them again, "Thank you teachers, brothers and sisters."

Leaving now?

The director sent Gu Xiaobai away, with a look of disappointment on his face, and complained to Pan Guoxiang: "You must be too upright, which made Xiaobai angry. There are hundreds of us, and we still have to eat, just eat...

…”

Pan Guoqiang did not speak. When he returned to the laboratory, he heard the students calling him: "Teacher, teacher, come quickly!"

"Teacher, listen!" The person who called him was a student who called himself Jiangcheng 306. Several of them were sitting in front of the computer, operating the simulation software, and humming softly along with the low voice floating in the air:

"Humph, I'm angry, angry..."
To be continued...