"Technical Principles of Nuclear Fusion Spacecraft Engines and a Roadmap for the Implementation of Related Projects?"

Pang Xuelin was slightly stunned.

A faint smile appeared on his face.

This reward isn't the best, but it's not bad either.

According to the current industrial level on Earth, the nuclear fusion spacecraft engine is basically impossible to realize in the short term, but referring to the drawings of this engine, a mature and reliable shortcut to the design of a commercial nuclear fusion reactor can be found.

This is another black technology that can change the global industrial pattern.

Pang Xuelin's eyes sparkled.

In the real world, lithium-air batteries have set off a wave of energy revolution around the world, and if they are paired with nuclear fusion reactors, which almost mean endless energy, their significance is far beyond the general industrial revolution, almost equivalent to human beings stepping from agricultural civilization to industrial civilization.

If nothing else, the price of electricity, which has gradually risen due to the popularity of lithium-air batteries alone, can be reduced by more than 10 times after the nuclear fusion reactor comes out.

At that time, low energy, coupled with 5G Internet of Things, artificial intelligence, electromagnetic catapult aerospace aircraft...... Pang Xuelin is sure that within ten years, human civilization will step into the category of interstellar civilization with half a foot.

"Then I got busy."

Pang Xuelin muttered to himself.

"Host, do you want to return to the plane of reality?"

The sound of the system rang in the ears at the right time.

"Let's go back."

Pang Xuelin smiled faintly.

……

In the next second, Pang Xuelin only felt that the picture flashed, and he felt that there was a warm body in his arms.

Pang Xuelin lowered his head, Qi Xin was wearing light pajamas, curled up in his arms like a cat, sleeping quietly and peacefully.

Pang Xuelin picked up the mobile phone on the bedside table and looked at it, half past three in the morning.

Even if you don't count the hibernation time, he has been in the Chinese Sun World for nearly thirty years.

The time interval of thirty years is enough to make the closest people become strangers.

Fortunately, after Pang Xuelin was modified by genetic optimizers, both his memory and the logical thinking ability of the brain were strengthened more than ten times compared with before.

Therefore, even though he was a little unfamiliar when he just came back, in less than a few minutes, the figures of Qi Xin, Yao Bingxia and others became clear again in his mind.

Pang Xuelin soon regained the state he had before entering China's Sun World.

It was still early to get up, Pang Xuelin didn't feel much sleep, he kissed Qi Xin's smooth forehead gently, carefully pulled his hand out from under Qi Xin's neck, and then picked up the notebook on the desk and came to the balcony.

Today is another full moon night, the moonlight is flowing down, and the mountain forest in front of the villa is dyed with a faint layer of silver gray.

Pang Xuelin opened the notebook, imported the information related to the nuclear fusion spacecraft engine rewarded by the system into the notebook, and then looked at it calmly.

A fusion spacecraft engine, essentially a stream of high-temperature, high-speed helium ions produced by nuclear fusion, is used to propel the spacecraft forward.

As a result, the engine is still a working fluid, and helium fuel needs to be replenished from time to time to keep the ship powered for a long time.

Compared to the non-working fusion spacecraft used by humans in the Dark Forest, this engine is a generation behind.

But for humans in the real world, this is completely unimaginable black technology.

According to the information provided by the system, the helium fusion engine, which can provide a maximum thrust of more than one million tons, can even accelerate a spacecraft to sub-light speeds as long as the fuel is sufficient.

Of course, under normal circumstances, the maximum speed that a spacecraft can accelerate to is equivalent to half of the fuel that the spacecraft itself can carry (the theoretical maximum), and the actual maximum is even lower.

Depending on the tonnage of the spacecraft, under normal circumstances, a high-power nuclear fusion engine can accelerate a megaton spacecraft to a high speed of 5,000 kilometers per second.

"If you have such a spaceship, you can basically sweep the world!"

Pang Xuelin looked at the approximate parameters provided in the technical data and couldn't help but smile.

He knew very well that if he wanted to build such a superspacecraft, the prerequisite was to complete the electromagnetic catapult space launch system project as soon as possible.

Only in this way can the payload be sent into space at the lowest possible cost, and such a supership can be assembled in space.

After reading the technical outline of the helium fusion engine, Pang Xuelin began to pay attention to the technical details inside.

Soon, Pang Xuelin's brows furrowed slightly.

Because the technical solution provided by the system is actually the third generation of nuclear fusion technology.

In fact, there are three generations of nuclear fusion technology, which are generally divided according to different fuels.

The first generation of nuclear fusion is also known as deuterium-tritium fusion.

Deuterium and tritium are both isotopes of hydrogen, but the most abundant isotope of hydrogen in nature, which consists of only one proton and one electron, accounts for the vast majority.

But unfortunately, it is very difficult for Geron to achieve fusion, because Geron will first fuse into helium-2, which requires two protons and two neutrons, and the mass of protons converted into neutrons is increased, and it also needs to absorb part of the energy released by fusion, but Helium-2 is not stable and will soon decay into deuterium!

Since the deuterium nucleus, fusion has started to hang, because there are neutrons in the deuterium nucleus, and there is no need to transform from protons for a long time!

Tritium-deuterium fusion H-2 + H-3 ==He-4 + n, fusion into helium four + a superfluous neutron, and the problem also comes from this excess neutron that escapes!

For fission, the nucleus of an atom is bombarded with free neutrons and produces fission!

This free neutron still has to be made, but in a nuclear fusion reactor it is a completely redundant thing!

Because neutrons are trapped by the nuclei of other materials and transmuted, a material becomes radioactive after a period of neutron radiation, and the entire properties of the material will also change.

The anti-radiation materials used for tritium-deuterium fusion not only have to withstand high temperatures, but also withstand the long-term bombardment of neutrons.

This is also one of the major technical difficulties in whether nuclear fusion can be commercialized.

As for the second generation of nuclear fusion, it refers to the nuclear fusion between deuterium and helium-3, which produces an order of magnitude fewer neutrons than tritium-deuterium fusion, and the materials currently used by humans to make fission and reactors can cope with such neutron bombardment.

As for the third generation of nuclear fusion, it refers to the nuclear fusion between helium three and helium three, and helium three nuclear fusion does not produce neutrons at all, so it is also called ultimate fusion.

Here, some people may ask, since helium trinuclear fusion has so many advantages, why not directly study helium trinuclear fusion?

There is another important issue at stake.

That's the specific binding energy.

The greater the number of protons and neutrons in the nucleus, the greater the energy that needs to be separated (iron is the peak), and the ratio of the binding energy of the element to the number of protons and neutrons is the ratio of the binding energy!

The specific binding energy from deuterium and tritium to helium is rising, and deuterium and tritium only need 5K electron volts to achieve ignition, but helium 3 has to make a lot of it.

The simple understanding is that deuterium and tritium are relatively easy to achieve nuclear fusion, and the energy required for helium to achieve fusion is much higher!

Therefore, it seems that it is a little early to hope for helium triple fusion when deuterium-tritium nuclear fusion is still flying in the sky!

Azimovich, a Soviet physicist and the father of the Tokamak, once said a very yellow and violent quote:

"When the whole society needs it, fusion will happen!"

The implication of this is that the energy level required for fusion is high, and it is unlikely that any single country can afford such a resource investment, and it will require the joint efforts of all mankind to achieve it.

This is the basis for cooperation with the International Thermonuclear Experimental Reactor (ITER).

Due to the technical difficulties and the small calculations between countries, the ITER project has been delayed again and again, and from the nineties of the last century to the present, the research related to nuclear fusion has still not made a fundamental breakthrough.

There are big problems such as plasma turbulence control, fusion reactor anti-radiation material research and development, etc.

Although Pang Xuelin had led and promoted the research of the nuclear fusion project in the dark forest world, most of his energy at that time was focused on how to fulfill the responsibilities of the wall-facing people and deal with the three-body crisis, and he did not spend much energy on technical details.

Therefore, although humans have successfully developed fusion reactors in the world of the Dark Forest, it is still impossible to replicate them in the real world.

On the contrary, it is the technical solution given by the system this time, which is more likely to be realized.

The only problem is that the scheme given by the system is not the magnetic confinement fusion route that is currently popular in various countries, but uses inertial laser confinement fusion.

Inertial confinement fusion is a method that uses the inertial action of particles to constrain the particles themselves, so as to achieve nuclear fusion reactions.

The basic idea is to use the energy provided by the driver to form plasma with the nuclear fusion fuel (deuterium, tritium) in the target pellet, and in a very short time when these plasma particles have not had time to fly around due to their own inertia, they are compressed to a high-temperature and high-density state through centripetal explosion, so that a nuclear fusion reaction occurs.

Because this kind of nuclear fusion is achieved by the inertial confinement action of the plasma particles themselves, it is called inertial confinement fusion.

However, there are also many problems in laser fusion, not to mention high-energy lasers, the biggest problem of laser fusion is that the product of density, temperature, and effective discharge time is large enough to achieve controllable fusion through plasma.

The product of these three is used as an indicator to measure the progress of fusion research.

The three-fold product of tokamak magnetic confinement fusion is much larger than that of laser fusion.

That's why the vast majority of countries, including China, are focusing on magnetic confinement fusion.

In the technical scheme given by the system, because the specific binding energy of helium triple fusion is high, the laser is directly used for ignition.

Pang Xuelin's attention was gradually attracted by the technical solutions in the computer, and he soon became addicted to it.

When you look at it, you don't know how time has passed.

I don't know how long it took, the morning light on the horizon was faint, and the sky was full of red clouds.

Before you know it, the sky is already bright.

"Alin, Alin!"

Pang Xuelin woke up from his contemplation, and in the bedroom, Qi Xin stood up and was rubbing his eyes and calling for himself.

Pang Xuelin's eyes sparkled, and hours of research yielded extraordinary results.

"Xiao Xin, what's wrong?"

Pang Xuelin's eyes turned to Qi Xin, closed the notebook, and entered the bedroom with a smile.

"Why did you wake up so early?"

Qi Xin muttered.

Pang Xuelin smiled and said, "I can't sleep, so I get up and check some information." ”

"Hug!"

The girl was clearly still in the mood to get up, squinting and opening her arms.

Pang Xuelin put the notebook on the desk, stepped forward to sit at the head of the bed, and gently hugged the girl into his arms.

The two hugged each other for a while, Qi Xin opened his eyes, suddenly turned over, looked at Pang Xuelin in a fog, and kissed him directly.

Pang Xuelin was slightly stunned, but quickly reacted and gave Qi Xin a warm response.

An intense morning workout quickly unfolded.

By the time it was over, it would be an hour later.

The two hugged each other and took a shower in the bathroom, Qi Xin changed into a white chiffon shirt, and the lower body was a pair of black high-waisted wide-leg pants with a ponytail, which looked elegant and fashionable, and the goddess was full of fan.

Pang Xuelin changed into a T-shirt and jeans, and the two went downstairs hand in hand, Zuo Yiqiu and Zhou Chen had already started eating in the restaurant.

Seeing the intimacy between Pang Xuelin and Qi Xin, Zuo Yiqiu pursed his lips, a little unhappy.

Pang Xuelin and Qi Xin didn't notice this detail, and happily greeted the two.

After breakfast, Pang Xuelin and Qi Xin went to Jiang University together, and Zuo Yiqiu and Zhou Chen naturally accompanied them.

Since the official launch of the Qiantang Laboratory, Pang Xuelin has been so busy that he has not touched the ground, either going to Beijing to participate in the coordination meeting of the electromagnetic space launch project, or discussing the synthesis route of new superconductors with Cao Yuan and them, or discussing the implementation path of dynamic APT technology with Shi Yigong and them, and also taking into account the compilation of the "Exploration" series of magazines.

Even those few students can only teach sheep.

Fortunately, Sophie and they are more self-disciplined, and Pang Xuelin entrusted Liu Tingbo to help carry them, so nothing happened for a while.

But today, Pang Xuelin had to come back.

After all, Jiang University is his alma mater, and he has just won the Fields Medal from St. Petersburg, so he naturally has to make a report at his alma mater as a big man of the Philippine Award.

This report meeting was not as grand as the previous ones.

In fact, both the teachers and students of Jiang University are used to this big guy coming up with an explosive result from time to time.

In their opinion, Pang Xuelin can't produce results, which is strange.

Earlier at the International Congress of Mathematicians in St. Petersburg, Pang Xuelin gave a report on Ponzi's 15 questions, summarizing 15 propositions that may have a significant impact on the mathematical community in the future.

At this report meeting at Jiang University, Pang Xuelin gave a certain degree of in-depth interpretation of the 15 questions of Ponzi.

The report ended in the afternoon.

Pang Xuelin, Liu Tingbo, and Xu Xincheng ate together in the faculty cafeteria, and was just about to go to his office at Jiang University when his mobile phone rang suddenly.