Li Yu quickly got the new Kodak pocket camera sent by Eastman, which was indeed a bit cumbersome to use.
Moreover, you need to go to a special photo studio to develop photos, which is also quite troublesome.
Konoe Akiyuki was very clever. When he watched Li Yu playing with the pocket camera, he quickly learned it and came over and said: "Sir, I have learned how to develop photos. I can handle this matter in the future."
She now wants to get intelligence information in every possible way, and like telegrams, photos are also a very effective way.
Li Yu is also planning to install darkrooms in her laboratory on Fifth Avenue and in her residence in China in the future, which will be much more convenient. At present, it seems that she is the only one who can do it, so she can only agree temporarily: "Be careful during the process."
Konoe Akiyuki and Li Yu pointed out that the materials such as film, developer, and fixer needed to develop photos are relatively expensive, so he said: "Sir, don't worry, I am very efficient."
As a spy, developing photos is of course one of the skills you must know.
Although Li Yu knows the general process, the development of photos is really a time-consuming task. The film must first be developed → fixed → washed and dried. Then the photo can be enlarged and printed out of the film. It must be developed again → fixed → washed and dried.
.
Anyway, it definitely requires a certain amount of technology and proficiency.
During the late Qing Dynasty and the Republic of China, photography was expensive, largely because of the cost of developing it.
However, modern people like Li Yu are inseparable from taking photos. In my previous life, I had to let the camera eat before using my chopsticks after a good meal. This problem is difficult to change.
One day later, the Bells found Li Yu and were about to leave for North Carolina.
Li Yu first sent a telegram to North Carolina, and the Wright brothers replied and said they would meet at Duke University first.
In fact, Duke University should be called Trinity College now, but it is easy to be confused with Trinity College in Cambridge. For convenience, it will be called Duke University from now on.
There is not much of a problem, because Duke University changed its name because of the donation from the tobacco tycoon Duke, and Duke had already donated a lot of money more than ten years ago.
Li Yu gave Bell a general introduction to the situation of the Wright brothers on the way. Bell said: "They sound like two very thoughtful people. They asked us to meet at Duke University. Could it be that they encountered technical difficulties?"
Li Yu said: "Maybe, after all, I have seen their first flight test. If you want to make improvements, the difficulty will be greatly increased. It is reasonable to seek help from the university."
Bell said: "That's it, that's why my Aeronautical Testing Association needs to recruit more powerful talents, just like you, Academician Li Yu."
Li Yu smiled and said: "Thank you, Mr. Bell."
Most of the famous universities in the United States are concentrated in the north, and Duke University should be the best university in the south of the United States.
The father of the three Song sisters, Song Jiashu, graduated from Duke University, as well as Apple CEO Tim Cook.
This school is quite famous for sports, especially basketball. Don’t underestimate it, the famous “Ivy League” is actually a college sports league.
Anyway, the United States attaches great importance to this aspect.
At first, I didn’t understand why prestigious American schools paid so much attention to students with expertise in a certain field, including sports. Later I learned that this is also a selection mechanism.
A person who can study well and also have a specialty can at least explain two things: first, the student himself is excellent; second, his family must have good conditions, and they both value education and have money.
Orwell Wright, the younger brother of the Wright brothers, came to greet him, "Academician Li Yu, I am so happy to see you! In accordance with your instructions last time, we have conducted key research on the balance control of the aircraft in the air and takeoff and landing.
, but we two brothers found that it involved many engineering problems, so we had no choice but to come to the university for help."
Li Yu said: "It's a very valid reason. Everyone adds firewood and the flames are high."
Li Yu introduced Bell to him again. Now that Bell is a famous person, Orville Wright certainly knows him: "It's an honor to meet you! We often use the telephone invented by Mr. Bell."
Bell said: "You admire my phone, and I also want to see your aircraft. In the Chinese saying of Mr. Li Yu, it is called courtesy."
"Everything you said is appropriate," Orville Wright said, "Please come in and we'll invite several students and lecturers from the School of Science to do theoretical research together."
Bell's heart tightened after hearing this: Their movements were so quick, maybe they would actually build a world-famous aircraft before him.
Duke University, a southern university in the United States, has many campuses that are very large. In addition to the tobacco tycoon Duke, another philanthropist, Julian Carr, donated a lot of land, so Duke University has no shortage of buildings.
The group entered a temporary classroom used by the Wright brothers, where several students were immersed in calculations, while the older brother, Wilbur Wright, discussed engineering improvements with a lecturer.
After saying hello, Li Yu looked at the calculations those students were doing and froze for a moment. He went over to the students and asked: "Which department are you from?"
The student replied: "Dear Academician Li Yu, we are from the Department of Mathematics, School of Science."
Li Yu took a closer look at their playing paper and asked: "Is this the Navier-Stokes equation (ns equation)?"
The student said: "Yes, sir."
Li Yu took a breath, what a guy! He actually did such a difficult thing!
But the research direction is correct.
Because the NS equation belongs to fluid mechanics, and aerodynamics is of course the field of fluids, the study of aircraft cannot escape from the fluid equations.
The ns equation is one of the key, and it is a set of extremely difficult partial differential equations.
Partial differential equations are required for physics majors. In fact, all engineering majors must learn this course.
As mentioned before, partial differential equations are very, very, very, very difficult, almost explosive.
So there is no need to know too specific, and it is impossible to know how much specific knowledge... it is enough to just know its difficulty, importance and applicability through general science.
It's really "magical", and that's not an overstatement.
Even the simplest partial differential equation, such as a one-dimensional heat conduction equation. The physical explanation means: there is a rod, the initial temperature is a specific value everywhere, and then a heat source comes from the right, and the solution is at a certain point.
temperature.
The form is very simple, with only one line and only one variable. Does it sound like a simple junior high school question?
hey-hey!
If you see the analysis and solution process, you will find that even if I copy the answer to you, you will not be able to understand it.
It’s simply a book from heaven!
This is only one dimension, with only one variable. In real life, it is all three dimensions. How to describe the difficulty of adding the Laplacian operator...
Just like the last second the teacher was talking about 11=2, he lowered his head to pick up a pen, and then looked up again, he was already talking about advanced college mathematics. The difficulty span is even greater than this.
Although Li Yu is not from the Department of Mathematics, partial differential equations are one of the mathematical tools that must be learned in physics majors, so he still has some exposure to them.
His scalp felt numb as he looked at what was in front of him.
Bell glanced at it, as if he was seeing Chinese or Japanese that he had never seen before, and asked in surprise: "Do you need this to build an airplane?"
Naturally, the students respected Bell very much, so they replied straight away: "Yes, Mr. Bell! Mr. Wright gave us a topic. At first we didn't pay much attention to it, but later we found it very challenging, so we organized ourselves to help."
Bell said: "I heard that your school focuses on theology, but there are actually people who understand such complex mathematical knowledge."
The student smiled and said: "Mr. Bell, there are people who love science in the south. I think God must also be obsessed with solving this most beautiful equation!"
Students should be religious, which is normal at Duke University, which is still called Trinity College.
Bell graduated from University College London.
When University College London was founded, the University of Cambridge and the University of Oxford in the United Kingdom were both ecclesiastical universities, so University College London intended to become a secular university alternative to religion.
Therefore, graduates of University College London are relatively more advocating for science.
This is why Bell always looked down on Duke University at first.
Bell asked Li Yu again: "Are you sure you want to use this thing to develop aircraft?"
Li Yu spread his hands: "To be honest, of course it is necessary. However, the Navier-Stokes equation will obviously not be solved for another hundred years, so it is not that indispensable."
Li Yu was telling the truth. After all, before he traveled through time, the NS equation was still far away from being solved.
Wei Dongyi and Wei Shen studied the ns equation, which was once popular on the Internet. But even if it is so popular, look at how many people explain what is going on. This thing really doesn’t look like it was studied by people. Just listen to the problem and understand it.
Not many people.
As one of the seven millennium mathematical problems, if the NS equation can make substantial progress, humans can truly explain why airplanes can fly.
Many people should have this question: Since the Navier-Stokes equation cannot be solved, how can we make the aircraft fly safely and smoothly?
For example, how do you know how much lift an airplane receives when it flies at a certain speed and angle? How much drag is it?
It’s just an empirical formula!
It is also necessary to explain in a little detail what the empirical formula is.
College engineering students should have seen many empirical formulas. Since it is called "empirical formula", it means that it cannot be explained by mathematical principles - because it is not derived at all!
This is also one of the reasons why the development of traditional disciplines was slow and limited in Li Yu's previous life.
There are many coefficients in the empirical formula. If you want to get these coefficients, you have to put the aircraft in a super large wind tunnel, then let some fluid visible to the naked eye flow through it, and get the value of the coefficient through experiments.
Then many different curves need to be measured: such as curves of various coefficients of the aircraft under different aspect ratios or different lead angles, etc.
Specifically, there are still many troubles.
However, although the empirical formula is very useful in many engineering fields, it has a big problem: it is specific, such as a specific wing shape, and cannot be changed at all.
If you want to design a wing of a new shape, you have to start over. The above empirical formulas are all useless and you need to put it into the wind tunnel again for testing.
Because the initial conditions have changed, the results are completely different. After all, the differential equation contains chaos.
However, once the Navier-Stokes equations are worked out, there is no need to do a wind tunnel!
As long as we have the shape of the wing, it is equivalent to having the initial conditions. We can even calculate all the flight data by hand, and there is no need to do experiments. Of course, computers are faster.
This can save more than tens of billions!
Therefore, Li Yu always felt that if Wei Shen could solve the ns equation, even if he was given a $100 million prize, let alone the $1 million prize for the Millennium Problem, it would be small.
Just kidding: As long as this equation is solved, humans can design a circular aircraft!
Because the best wing shape can be designed under a certain fluid state. At that time, UFO may really be realized.
In short, this is why Li Yu dared to give the airship information to Little Japan.
——It is impossible to solve the ns equation!
No matter how much money Japan invests, it will not be of much help to future aircraft development. It is time-consuming, laborious, and thankless.
I don’t know if this is a conspiracy or a conspiracy?
Li Yu knows little Japan very well. They are very clever and tricky. Without some high intelligence, it will be difficult to control them.
It has to be useful for the present, it has to be very difficult to do, and it has no future prospects! It can’t really help little Japan.
It's really hard to find many things like this.
As for the student from Duke University in front of me, it is a different situation: just like after Chen Jingrun studied the "12" Chen's theorem, many civil scientists rushed to study Goldbach's conjecture.
This student obviously does not know the horror of the ns equation.
To put it more bluntly, his mathematical foundation is not in place at all, which is why he made such a rash attempt.
Li Yu kindly reminded: "Engineering can sometimes use simpler methods."
The student said: "I understand what Mr. Academician means, but wouldn't it be more convenient to solve the equation and save a lot of money?"
Li Yu said with a smile: "The research on engineering technology is basically a gold mine. It's normal."
The student seemed very determined: "I think God must know everything, and the secret of the airplane is hidden in the Navier-Stokes equations!"
People with faith are really persistent, and Li Yu couldn't persuade them at all.
Brother Wilbur Wright said to Li Yu: "Sir, last time he said that he could provide another engine. Can we make some requirements for it, mainly several important parameters, such as weight, power, etc."
This was something Li Yu had already promised, so he said: "Of course, Mr. David Buick has been conducting research on engines, and I will give you an engine that satisfies you."
After taking a rough look at the designs on paper, Bell wanted to see the real machine even more, so he said impatiently: "Let's go to the hangar as soon as possible!"
The Wright brothers respected Li Yu and Bell very much. Since Bell said this, they could only stop researching the data at hand and take them to see the Flyer 1 that was used last time.
It has to be said that compared with the designs of Bell and others, the aircraft designed by the Wright brothers was really too advanced in terms of shape.
Bell asked the Wright brothers to tow the plane out and conduct another flight test.
Just like last time, the plane flew two to three hundred meters.
Even so, Bell was astonished.
“It turns out it really can be achieved!”
In addition to Flyer 1, there is another Flyer 2 under development in the hangar.
However, the Wright brothers' patent had not yet been approved, so they could not show Bell more technical information.
But Bell finally made clear the direction of his research.
Bell asked Li Yu privately: "Sooner or later, this patent will belong to the Wright brothers. Can we continue to research it?"
Li Yu said: "Just like cars, aircraft still have many aspects that can be improved and there is still much room for improvement, especially if we can carry out better layout design."
Bell didn't know much about aerodynamic layout, but when Li Yu said this, he had a general idea.
"You must join my Aviation Experimental Association!" Bell told Li Yuzansan.
He was afraid that Li Yu would run away.
Li Yu smiled and said: "I know, I still have to be the founder who provides money and technology."
Bell was very satisfied: "It seems that I can fly to the sky in a powered aircraft once in my lifetime!"
Not only him, Li Yu is also looking forward to it.
In addition to those that run on the ground, Li Yu also wants to do those that fly in the sky and swim in the sea.
They are not just for fun, they will be of great use in the future.