Chapter 171 'Things About My Hands Rubbing the Plane After the Song Dynasty Coup' (6.8K)
Throughout the long history of human civilization, our ancestors have almost never stopped looking up to the sky.
Why do humans yearn for the sky?
Before Xu Yun traveled to the Song Dynasty, he had heard an explanation based on material particles:
As we all know.
All elements in the universe come from supernova explosions.
It produces everything you can see in the physical world, including yourself.
The atoms that make up your left hand and the atoms that make up your right hand may come from different stars.
When you look up at the stars.
What your eyes are looking at may be the galactic material that makes up your eyes.
Your thoughts are racing and your brain cells are transmitting nerve impulses.
Every nerve transmission may be the first handshake between matter across galaxies.
You look up to the sky.
Because you come from the sky.
Xu Yun didn't know whether this statement that was tenable in science could be applied to the field of idealism, but he knew one thing very well:
In the long history of Chinese civilization.
Indeed, countless ancestors expressed their yearning for the sky either through writing or through practice.
For example, Wang Xizhi of Jin Dynasty wrote in the "Preface to the Lanting Collection":
“Looking up at the vastness of the universe and looking down at the abundance of categories, it’s a pleasure to wander around and enjoy the sights and sounds, which is enough to entertain you.”
There is also Li Bai's "Yuan Dan Qiu Song":
"Walking around for a long time, stalking the stars and rainbows, riding a flying dragon with ears blowing in the wind, crossing rivers, crossing seas and connecting to the sky, I know that your wandering mind is boundless."
in these poems.
The author directly or indirectly expressed his desire to fly into the sky, and also expressed his own attitude towards life.
Looking down at the world from a high place makes you happy in life.
And some people are different from Li Bai and Wang Xizhi. They may not have literary talent, but they have a heart to explore.
For example, the time Xu Yun is currently living in is 1100 AD, the first year of a new century.
Follow the historical trajectory.
27 years later, the Jin people destroyed the Northern Song Dynasty and the two emperors were kidnapped.
One hundred and thirty years later, the Yuan Dynasty destroyed the Southern Song Dynasty, and the country was lost to foreigners.
But the Yuan Dynasty only lasted less than a hundred years, and the sun and moon would reopen the Song Dynasty.
At that time, there will also be a Wanhu named Tao Chengdao.
Tao Chengdao was proficient in gunpowder and played a major role in Zhu Yuanzhang's conquest of the world, but he himself was always full of curiosity about the sky.
Finally, in 1390 AD, Tao Chengdao made a decision:
He wants to fly!
According to Tao Chengdao's plan.
He will tie 47 rockets to the back of the snake-shaped seat and use the gases produced by the burning solid explosives in the rockets to eject outwards.
The rocket will fly forward due to the reaction force of these gases, and several rockets are tied to the seats, which will drive the seats and the rockets together.
In this way, when he sits on the seat, he will be propelled into the sky by the thrust of the rocket.
Other than that.
He also arranged two huge kites on the seats.
This allows him to continue flying and land smoothly.
The famous Qian Lao of later generations once described the scene when Tao Chengdao flew into the sky:
"At that time, his servants were frightened, but when faced with the worries of the people around him, Tao Chengdao looked up to the sky and laughed and said, Flying to the sky has been my long-cherished wish for thousands of years. Today, even if I am broken into pieces and my blood is splashed in the sky, I will still do it.
Future generations will find a way to explore the sky. You don't have to be afraid, come and light the fire quickly!"
Seeing this, the servants had no choice but to light a fire according to Tao Chengdao's request.
After a while.
With a loud noise.
Tao Chengdao was carried into the sky by the thrust of the rocket.
Following the second stage plan designed by Tao Chengdao, the gunpowder was ignited to continue to increase the height of the device.
However, just as the disciples and servants on the ground were cheering for joy.
Only an eardrum-shattering explosion was heard.
In the sky, Tao Chengdao and his device turned into a fireball and quickly fell from the sky...
The first human "astronaut" who wanted to use rocket thrust to launch into space died. Tao Chengdao's disciples and servants buried him on Wanjia Mountain...
However, Tao Chengdao unfortunately passed away while pursuing his dream.
His heroic deeds have been inspiring generations of Chinese astronauts and have won recognition in the world's aerospace field.
He is internationally recognized as the first pioneer in history to use a manned rocket to attempt space flight. The International Astronomical Union also named a crater on the moon "Wanhu" to commemorate this great man.
If Wang Zhen, Zong Ze and Zhang Shuye represent the integrity of China.
So what Tao Chengdao embodies is the spirit of seeking knowledge and exploration of the sages.
Among these sages, Lao Su, the greatest scientist of the 11th century, is naturally indispensable.
Every time he looked up at the sky, he would have a thought in his mind:
If people could fly to the sky and overlook the ground, what a wonderful scene it would be...
Magnificent mountains and rivers, and all kinds of conditions in the world can be seen at a glance.
So a long time ago.
He then tried to make a wooden kite, hoping to use the power of the wind to achieve the effect of reaching the sky, and to try to conquer the sky.
However, due to the lack of sufficient knowledge and theory, the idea of wooden kites ascending to heaven ultimately ended in failure.
Now as his body ages, Old Su already has a premonition in his heart:
I don’t have much time left, so there is probably no possibility of realizing this obsession.
Maybe I can only bid farewell to this world with regrets in a year or two...
But what he didn't expect was...
With the appearance of Xu Yun, certain things seem to have vaguely changed...
airplane?
Does it mean a flying wheel or a flying machine?
No matter which of the above possibilities, can it really take a person to the sky?
To know.
An adult's weight ranges from a hundred kilograms to more than two hundred kilograms.
Including the weight of the load, the most conservative estimate is more than 200 kilograms, right?
How can such a heavy object fly?
But Xu Yun has already proven his ability before, so the credibility of his words is not low...
Then Lao Su paused for a moment. Considering the importance of ‘auspiciousness’, he decided to learn more about the inside story:
"Xiao Wang, is there any principle that can explain the airplane thing you mentioned?"
This chapter is not finished yet, please click on the next page to continue reading the exciting content! "The principle..."
Xu Yun thought for a while and took out two pieces of paper from his body - he had mentioned before when he was in Fan Lou that he would always carry paper and pen with him.
Then he held one end of the paper with both hands and let the paper hang down naturally.
Asked Lao Su and Xiao Zhao:
"Your Highness, Sir, do you two still remember the experiments you did in class?"
Old Su and Xiao Zhao looked at each other with thoughtful expressions on their faces, and after a moment they said:
"Of course I remember, it seems to be called Bernoulli's principle, right?"
Xu Yun nodded:
"good."
Then he paused and continued:
"Your Highness, sir, since you two still remember Bernoulli's principle, is there a possibility?"
"For example, changing the paper into a fixed object, using techniques to create a huge difference in the gas flow rate up and down..."
"In this way, will it be possible to lift objects into the air like pieces of paper floating?"
Students with good memories should still remember it.
When Xu Yun first met Xiao Li, he once demonstrated an experiment for her by blowing paper pieces.
Later, Xiao Li specifically asked Xu Yun about this in class. Xu Yun demonstrated another experiment in high school in order to facilitate explanation:
Hold one end of the paper with both hands, let the paper hang down naturally, and then blow air between the two papers.
Then blow and blow and you will find...
The two pieces of paper were actually stuck together.
In high school textbooks, the above two experiments will be attributed to Bernoulli's principle:
Look, the flow rate above is high and the pressure is low, so the paper floats.
But actually...
This is wrong.
The paper blowing that Xu Yun demonstrated to Xiao Li had nothing to do with Bernoulli's principle.
In fact, this is also the most widely spread misunderstanding of Bernoulli's equation.
Taking into account the information barrier problem of some idiots...ahem, lay readers, a brief summary is:
Bernoulli's equation is established along the same streamline, not between different streamlines.
The deflection direction of the paper does not depend on which side the airflow is at all, but depends on the angle between the direction of the airflow and the paper, and the viscosity.
At the beginning.
The paper hangs vertically.
Blowing air above the paper will take away the air on the right side of the paper due to viscosity.
As a result, a low-pressure zone will be formed.
Due to the existence of this low-pressure zone, the paper will float upward and to the right.
When the paper floats, the streamlines will bend downward.
This will eventually make the streamlines and the paper closely adhere to each other.
At this time, the flow of air is no longer straight forward, but in a downward arc. This is a swirling field.
Therefore, the downward bending streamlines will generate centrifugal force, and this centrifugal force will bring the paper up.
The real name of this effect is called the Coanda effect, not Bernoulli's principle.
Very simple and easy to understand, right?
But in high school classroom.
When talking about the principles of airplanes, teachers not only fail to explain the Coanda effect (in fact, quite a few people may not even know that they are wrong), but they often extend the above paper example again.
That is, replace the pieces of paper with wings:
For the wing, the upper surface is more convex, and the speed of the airflow passing over the upper surface is higher.
Therefore, a pressure difference is also generated, and this pressure difference is the source of lift.
With the above explanation coupled with the paper experiment, most people suddenly understand the principle of aircraft flying in the sky:
Oh, it turns out that the principle of airplanes is so simple...
Ever since.
A situation of making mistakes again and again appeared - the principle of airplanes is Bernoulli's principle.
In fact, if you are willing to think about this statement, you can easily think of two refutation questions:
First, why can the aircraft in the air show fly upside down?
Second, a kite is just a big flat plate. Why can it fly without power?
Of course.
I want to think about these two questions, and I don’t recommend refuting the teacher in class.
Otherwise, it is very likely that he will be punished by being punished and given a set of rewards for copying homework, and he may even have to be criticized by the class teacher.
all in all.
So far, including Bernoulli's principle, Newton's third law, Ventley effect, Kutta-Zhukovsky law, and many improved laws, it is actually difficult to explain them perfectly.
Lift problem.
Why airplanes can fly is still a mystery.
It is said that the Nobel Prize is far away. In fact, if the principles of many common phenomena in life can be successfully solved, the Nobel Prize will be almost within reach.
But on the other hand,
It’s something I mentioned a long time ago:
The Song Dynasty is not the 21st century. For the basic understanding of this era, there is actually no need to be completely correct in certain concepts.
A more general explanation is easier for people to understand.
Therefore, when Xu Yun was explaining the reason, he directly put Bernoulli's principle on the piece of paper.
That is to say, in a flowing fluid, the greater the flow velocity, the smaller the pressure.
Now, in order to save some trouble, he continued to extend the paper to the wing, and still put his hat on Bernoulli's principle:
"So if we can use some means to provide a large amount of boost in a short period of time, we may be able to send the aircraft into the sky."
"If I remember correctly, Fengling Yueying Sect also has a skill called loudspeaker."
"This object is not large in size, but it can amplify an ordinary person's voice several times, so it is not troublesome to reproduce it."
"If His Highness can fly by plane and speak to the people through loudspeakers, there will no longer be any need to worry about the residual influence of the deposed emperor."
After hearing what Xu Yun said, Xiao Zhao's eyes suddenly lit up.
Although in the legends of past dynasties, every emperor seems to have magical powers.
For example, Liu Bang killed the white snake, Gao Huan had the strangeness of red light and purple energy, etc. It seems that you can't be an emperor without some strangeness.
But there is one thing to say.
These so-called visions are basically rumors that emerged only after he ascended the throne, and their authenticity is doubtful.
There are actually very few supernatural phenomena that appear in the public eye, and even if they do exist, they are most likely just coincidences.
But if he could fly high into the sky during the enthronement ceremony and utter "thunder sounds", that would be a real vision in public!
The effect is definitely countless times higher than any amnesty. In the game, it is the bug effect of 40 people's hearts!
Think of this.
Xiao Zhao suddenly couldn't sit still and asked Xu Yun quickly:
"Master Wang, I wonder how many materials are needed for the airplane and how long it will take to make it?"
When Xu Yun heard this, he immediately looked thoughtful.
be honest.
Although he is a veteran in the DIY circle, it is still difficult to make an airplane with his hands in the ancient context.
Just based on the halo prompts.
The heaviest score of the task was related to the technical difficulty, so he had to come up with the concept of an airplane, otherwise he would just build a hot air balloon and be done with it.
When talking about aircraft, the first thing to mention must be the type.
Generally speaking, aircraft are mainly divided into two categories: jet aircraft and propeller aircraft.
Among them, propeller aircraft are the most primitive powered aircraft, and they are also the ones we see in old movies and documentaries.
It mainly uses the rotation of the propeller to push the air behind the aircraft, and uses its reaction force to push the aircraft forward.
Specifically, according to the difference in power, they can also be divided into piston aircraft, turboprop aircraft, etc.
However, some aviation enthusiasts will separate out the piston aircraft and define it as a third independent category of aircraft - the number of these people is not large, and it can only be regarded as an unpopular genre.
Of course.
Although propeller aircraft have a long history, they have not completely withdrawn from the aviation stage. The proportion of propeller aircraft currently in service is probably less than 20%.
Jet aircraft are now the mainstream aircraft type. Most of the civil airliners we take now are jet aircraft.
Compared with propeller aircraft, the classification of jet aircraft is more complicated.
For example, it can be divided into turbojet, turbofan, turboprop and turbine shaft, etc.
But despite the fact that the plane seems very high-end, if you don’t consider the rating, there are several types that are quite easy to rub by hand.
For example, a very simple pulse jet engine.
The English name of this thing is also called Pulsejet. During World War II, it was specially used to launch V1 missiles, which only hit John Bull.
Although to modern eyes.
Pulsejet has low power, large vibration and noise, unstable operation, short life and uncontrollable, and the controllable range of output power is very narrow.
But from a technical point of view, the pulse jet engine is too simple:
Its main component is a pipe, not even a seamless steel pipe.
Block the front of the pipe with a one-way valve to let air in, then insert an oil pump and igniter and you're done.
When starting, use compressed air to flush the front valve, then match the ignition, and it will start instantly.
Xu Yun had used his hands on three or four simple Pulsejets in his previous life, and the weight ratio was as high as 500.
However, considering that this kind of non-technical design does not have enough gold content, the score will most likely not be too high. I guess it may be better than a hot air balloon.
Therefore, Xu Yun hesitated again and again and made a bold decision:
Design your own engine!
be honest.
This is undoubtedly a very difficult approach.
Although Xu Yun knows a lot about internal combustion. Although he did not engage in engine construction at Chengdu Aircraft Corporation of China after graduation in his previous life, he was familiar with a lot of knowledge.
But to put it bluntly, this is the Song Dynasty after all.
There was no supercomputer, no sophisticated production equipment, and the conditions were completely different from those of later generations.
Other than that.
Flow field analysis, compressor, turbine, rotor synchronization, clearance control, fuel oil, bearings, and even the shape of the combustion chamber, all cannot be wrong at all.
On the contrary, the extremely difficult blade processing in later generations can be relatively easy. After all, it is only a short-term preparation for the enthronement ceremony.
Judging from Da Song's current skill level, it is quite easy to pile up a set of blades with a 60-hour lifespan using money.
But the whole process was difficult to reverse, and Xu Yun had an inexplicable premonition in his heart:
The score of this task is very important, the higher the better, and it must not be done perfunctorily.
This premonition even made him feel a little heavy, as if...
He is not the only beneficiary.
Think of this.
He couldn't help but raise his head, looked at Xiao Zhao, and said:
"Your Highness, if you want to build an airplane, ordinary people will probably need a lot of manpower and material support."
Xiao Zhao waved his hand generously. He was not a nagging person:
"Young Master Wang, just ask!"
Xu Yun thought for a moment and said:
"The first is a large amount of iron ore, craftsmen with basic skills, and a suitable preparation site."
"The second is some rare resources, such as... fallen stars, and the more the better."
The so-called falling stars refer to meteorites.
In addition to iron and nickel, there are also other rare metals found in meteorites.
Although the content of these metals is not necessarily particularly high.
However, the number of meteorites accumulated in the treasury of the Song Dynasty should be quite large, and theoretically there is a high probability that some special resources can be obtained.
As Song Zhezong's biological brother, Xiao Zhao knew something about some of the storage items in the palace, so he readily agreed:
"There are about hundreds of fallen stars in the palace. Some are no bigger than a nut, but some are as big as a water tank."
"If it's still not enough, I can also contact aristocratic families from all over the world to definitely meet the needs of the young master!"
Xu Yun nodded with satisfaction and continued:
"The other thing is that there are a lot of math bachelors, such as Mr. Tongyu, etc. The more, the better."
"As for the time...it will take at least six or seven months."
"Six or seven months..."
Xiao Zhao repeated the time and turned to look at Lao Su.
Old Su thought for a moment and said:
"His Highness can temporarily take charge of the government as a supervisor of the country. Not to mention half a year, a year is not a problem."
Xu Yun nodded slightly, this answer was within his expectation.
After all, Xiao Zhao also has to take time to accept Zhao Ji's remaining power, which is not that easy.
Even Zhao Ji, who has a legitimate reputation in history, took more than half a year to complete it.
Then he suddenly thought of something again and added:
"By the way, there is something else that needs to be prepared."
