This civilization is very strong, but the technology tree is a bit crooked.

Chapter 41 When the black eagle fell, there were only a few pieces of skin left

"It's so scattered, what should I do if I have to return it?"

Chen Yi raised a key question.

Although the Black Hawk was shot down into the airspace and picked up.

But not surprisingly, the protest and the request for return have now been sent over.

According to some unspoken rules among major powers.

Unless you want to completely tear your face apart, Black Hawk still has to return this matter after some negotiations.

This time ranges from three to five months to a year and a half.

In any case, the opposite side will not let this Black Hawk, which has great strategic significance, stay outside for a long time, so that others can fully understand the Black Hawk's technology.

What everyone can do is to mobilize as many scientific researchers as possible before the return date arrives.

Study and understand the technology contained in the Black Hawk, and at the same time gain more benefits at the negotiating table.

But now that the Black Hawk has been dissected like this, how can it be returned.
"It's simple. The Black Hawk crashed into the sea at an altitude of tens of thousands of meters. No one knows how many pieces of the Black Hawk are left except us."

Professor Zhang explained with a smile on the side: "We can rush there in time to help Youguo retrieve some broken parts, which is not bad.

But maybe, we didn't go in time, the Black Hawk even lost its engine and sank to the bottom of the sea. "

"Yes, the engine has been "sinking into the sea", they speak nicely, we can help to "fish" the engine and return it.

The words are not good, let alone the engine, it is estimated that even the main body of the Black Hawk's fuselage has sunk into the sea.

We passed slowly, and there are only a few pieces of skin left on the sea surface."

The other professors next to him answered the conversation, their faces full of expressions that you understand.

"."

Chen Yi was shown off by this operation.

Sure enough, on the operation.

Still have to see a professional.

A folk player like him is obviously much worse.

Chat for a while.

Chen Yi went over to the main body of the fuselage, and carefully checked the structural design of the fuselage, as well as the stealth design.

Although small planes and large planes are both planes, their structures and designs are quite different.

The structural stress and aerodynamic layout involved, including the load on the fuselage during acceleration maneuvers, and the internal compression and injection structure of the engine, are not as simple as scaling up in equal proportions.

Instead, some are proportionally enlarged, some are exponentially enlarged, and some are enlarged in shape, and the aerodynamic parameters or combustion parameters need to be adjusted to reduce.

These differences can be as complex as a complete redesign of an aircraft.

"It turns out that in the structural design of large aircraft, because the windward side is raised, in addition to the higher requirements for the material strength of the fuselage, there are also higher requirements for the lift coefficient and drag coefficient of the aerodynamic layout.

In addition, the resonance, vibration, thermal expansion and contraction of the fuselage also need to be strictly controlled.”

Chen Yi studied it for ten minutes, and he probably had an idea in his mind about the structural design of the large ultra-high-speed aircraft.

As a metaphor, it is like a small piece of iron, even if it is accelerated to supersonic speed, because of its small size and simple structure, the iron sheet will not be greatly affected.

However, if the iron sheet is replaced with a sheet metal aircraft, because the volume increases and the structure is more complex, the stress and air resistance of each component are different.

Once supersonic, it will collapse in an instant.

This is the same as the rocket return capsule that failed to return to the ground in space. The entire return capsule will only collapse into large and small fragments.

But the fragments after the collapse will not continue to collapse into smaller fragments.

This is because the volume and structure are different, and the various forces that the high-speed state bears are also different.

As for thermal expansion and contraction, resonance, vibration, etc., the same is true.

Chen Yi's drone is less than 2 meters in size, and the airframe has not changed much between the normal temperature state and the thousands of degrees Celsius heat generated by supersonic friction.

But if it is replaced by an 18-meter-high black eagle, when flying at supersonic speed, the entire fuselage will expand by more than 50 centimeters compared to the normal temperature of the ground due to high temperature.

The gaps caused by these expansions, the deformation of the fuselage, etc., will cause the entire fuselage to collapse at high speed if they are not well controlled.

"Xiao Chen, don't be so busy looking at the fuselage.

Check out the real heart of this Black Hawk, the tri-pack of scramjets. "

Seeing that Chen Yi had been studying the structure of the Black Hawk's fuselage, Professor Zhang walked over and pulled Chen Yi over to the disassembled scramjet on the other side.

"What is there to study about this, didn't I give a better rotary detonation engine?"

Chen Yi walked over and looked at the scramjet that was completely scrapped as the battery penetrated through the side wall of the combustion chamber, and half of the area was melted and solidified again due to the high temperature of the combustion chamber.

He has no design experience for large aircraft.

Even if you have mastered the knowledge of aerodynamic layout, engine manufacturing, and aircraft design, you still need to relearn and re-study.

But Professor Zhang and his group are all masters who have designed and researched aircraft for decades.

It has led the domestic aircraft development process from imitation to surpassing, from import to export.

I know the characteristics of aircraft and engines of various sizes almost by heart, and I can't do it with rich experience.

With the technical details of the rotary detonation engine he provided.

Even if it is just a miniaturized rotary detonation engine, it is not difficult to convert it into a super engine for large aircraft.

In this case, what is the purpose of studying scram jets?

Wouldn't it be better to go directly to the rotary detonation, one step in place?
"The rotary detonation engine, which is an advanced version of the rocket engine.

Although Xiaochen added a turbojet structure to your design, it was made into a combined turbojet + rotary detonation engine.

But in the critical airspace near the Karman line, there is no ram performance and scram.

The performance, efficiency, and adaptability of the engine are still much worse than the three-combination supercombustion engine of the Black Hawk.

Now the tactical strategy of air combat is gradually developing towards high altitude, ultra-high speed, and critical space.

Without scramjet engines, we will suffer a lot in the future. "

Professor Zhang explained with a wry smile.

"It's enough to go directly to the space fighter and occupy a higher airspace." Chen Yi blurted out.

But after speaking, I realized something was wrong.

There is an obvious barrier between space and star space.

--atmosphere.

If you want to return from space, you must precisely control the speed and angle, otherwise you will be burned by the atmosphere.

Facing the atmospheric obstacle of returning to the planet, no matter how handsome your space fighter is, unless it is equipped with lasers and becomes high.

Otherwise, it would be difficult to pose any threat to combat aircraft in the atmosphere.

Realizing that something was wrong, Chen Yi also started to get serious: "What is the combination of this Black Hawk's engine?"

"The three combinations of turbojet + sub-ramjet + scramjet have the characteristics and advantages of three kinds of engines."

"I'll take a look."

Chen Yi walked up to the Black Hawk engine, which was much taller than his own, put on a protective mask, got inside with a flashlight, and inspected it carefully.

Professor Zhang and a group of other experts and senior engineers stood outside and waited together, looking forward to watching Chen Yi busy inside.

I know that Chen Yi's rotary detonation engine was designed by Chen Yi, a man-made drone for landing on the moon, and an ion-propelled drone in the atmosphere.

They all knew that Chen Yi was no less accomplished than them in the fields of aircraft design and manufacturing, engine design and manufacturing.

In addition, young people have big brains and more active thinking.

If you don't necessarily see the mystery of the Black Hawk super-combustion engine, it will give you different inspirations and insights.

Chen Yi studied for a while, and walked out with some regrets.

"The damage is too serious, and I can't see the key point of this engine to achieve a three-combination"

Before the words were finished, everyone was disappointed at once.

Professor Zhang patted Chen Yi on the shoulder and comforted him: "It's okay, it doesn't matter if you don't see it for a while.

During this period of time, Xiao Chen will stay if he is free, and will be treated as a specially hired expert.

We strive to research as many key technologies as possible before the return of the Black Hawk. "

"Yes, technology can't be broken through in a short while. I'm very happy that a technology like scram can be put into practical use within three years."

"Take your time, the food in Rongfei's canteen tastes good, let's enjoy the food slowly and study slowly."

As if they were afraid that Chen Yi would have some psychological burden, some other experts and senior engineers quickly picked up the conversation, smiling and reassuring that the matter could not be rushed.

"Wait, I haven't finished talking yet."

Looking at the group of people who were clearly feeling the most uncomfortable but comforting him, Chen Yi thought for a while: "I don't know how this Black Hawk engine can achieve three-combination scram.

But for the three-combination engine of turbojet + sub-ramjet + scramjet, I do have some feasible ideas.

If the model is large enough, you can also design a four-combination engine with a rotating detonation structure, or even a five-combination turbofan. "

"what!?"

"Is this a joke?"

Professor Zhang and a group of people were stunned, looking at Chen Yi in disbelief.

　PS: 2600 words, 6000 were updated today, so many updates during the free period are relatively small, and when it is on the shelves, we will guarantee a minimum of [-] updates every day.Finally, ask the readers for follow-up, monthly tickets and recommendation tickets.

　　
　
(End of this chapter)