Chapter 262 Composite Propellant Rocket
"Okay, I'm going to start talking to Shenhai right away. In a sense, this is the end of my nomadic life. I just don't know when you can return to Shenhai."

Lin Jia was smiling and joking at first, but when talking about when Chen Yuanguang would return to Shenhai, he suddenly felt a little melancholy.

"I don't know either." Chen Yuanguang was also melancholy, "But it's not just me who will be in Mianyang. Later on, some people will be transferred from Guangjia Aerospace to Mianyang.

Participate in the composite rocket program with China Aerospace.

I will send you the list later. You can tell them to prepare and communicate clearly with their families. There will be travel subsidies, and we will help them solve housing problems.

It is estimated that it will last from the third quarter of this year to next year, and the specific end time will depend on when our composite rocket is successfully launched. "

"it is good."

After thorough investigation and risk elimination, the selected people obviously included Yang Jiashan and Lin Tianmin.

As a core researcher and developer of the former Long March rocket, Yang Jiashan had already gone through countless rounds of review.

As an undergraduate, master and doctoral student of Beihang University, Lin Tianmin went to America for the first time and experienced a series of experiences that witnessed his shameless behavior, such as being framed by a black man's body, spending several days in the interrogation room, being woken up in the middle of the night, etc. However, he successfully passed the test after a thorough investigation.

On the plane to Mianyang, Lin Tianmin seemed very excited: "How will the composite rocket be designed? Although NASA, American and Japanese commercial aerospace agencies have had some designs for this.

But these designs are still in the imagination stage and are a long way from actual launch.

Not to mention launching, it hasn't even passed the feasibility study.

And this time we’re actually going to send a rocket into space.”

Yang Jiashan was obviously not as excited as he was, which was easy to understand. Lin Tianmin was a single man, unmarried and not even in a relationship. Being able to participate in such a project made him very excited.

Speaking of this, at a time when the financial industry is generally seeing salary cuts, Guangjia Aerospace employees have a very high priority in Shenhai's blind date market, even higher than the employees of the core departments of most Internet giants.

It is quite similar to the preferential treatment that Alibaba employees enjoyed at the blind date corner in Hangzhou during Alibaba’s heyday.

“It’s really challenging, and it’s interesting just from listening to it.

But the more challenging it is, the lower the possibility that we can return to Shenhai early.

Alas, I don’t want to be separated from our two places for too long. Now is different from the last century. It is easy to have problems if we are separated for a long time.

When I was still working at China Aerospace, there were many cases among my colleagues where their marriages broke down due to separation.

Look at Ms. Lin. She is in the best mood every Monday because she just met with the God of Light at the weekend. Then her mood drops all the way. When it comes to the weekly meeting on Friday, her negative energy is overflowing. Once there is a mistake or something that does not satisfy her, she will start to criticize violently.

This is the downside of living apart.

When Guangshen was still in Shenhai, Mr. Lin was always gentle in meetings, never scolding anyone, and never speaking too loudly. "

Yang Jiashan complained fiercely.

Lin Tianmin laughed when he heard it, but he didn't dare to laugh. Yang Jiashan was just complaining casually. If he laughed, it might be reported to Lin Jia and he would be in trouble.

"I believe in Guangshen. This project can't take three to five years." After Lin Tianmin finished speaking, he suddenly realized: "I feel that what Mr. Lin said is right. We are indeed dependent on Guangshen.

Before the change, for this kind of unprecedented and groundbreaking project, let alone three to five years, even if it took ten to eight years, if we could produce a composite-powered rocket, I would think we were amazing and successful.

Now, I think it takes three to five years to complete it. "

"That's right, the question is why geniuses don't rely on others?

In the past, human society’s technological progress relied on the top geniuses.

In the past, China did not have similar geniuses to rely on. Of course, what we did was also following the foreign approach, the path from 1 to 100, and the degree of reliance on geniuses was not that high.

But now a lot of what we do is work from 0 to 1, and we cannot achieve our goals by piling up ordinary geniuses. We have geniuses like the God of Light to rely on, so why not do it?
When I first joined Guangjia Aerospace, I called him Mr. Chen, and later I was willing to call him the God of Light.

I feel very fortunate to have such genius to rely on, and we may be able to complete in just ten years the path that would have taken fifty years for commercial spaceflight to mature.

From a higher dimension, it is even a lucky thing for all mankind. Only with hope can we prevent a global war. "Yang Jiashan said with emotion: "So even if the American assassination of the God of Light succeeds, it will only gain short-term benefits, and what will be lost is the future."

The two of them spoke in a very low voice, and people nearby could only hear fragments of their conversation even if they pricked up their ears.

After listening to this, Lin Tianmin nodded in agreement. Chen Yuanguang had expressed similar views many times in Guangjia Aerospace, that is, to help humans compete for the incremental cake by going to outer space.

This view was generally not believed by everyone at the beginning, and was considered to be empty talk. However, considering the treatment, people just kept it empty talk.

In recent years, people have become more and more convinced of this and believe that what they are doing is a grand cause that will be written into human history.

This has a lot to do with the high reputation of Guangjia Aerospace in the recruitment market.

"Everyone, long time no see. Why do I feel that everyone's hair has become thinner?" The next day, the Guangjia aerospace R&D personnel from Shenhai were not given a day's rest and were directly brought to the conference room to understand the situation. Chen Yuanguang first teased them.

After that, an employee standing in front of Chen Yuanguang complained: "Guangshen, their hair is thinning, but I don't have it."

After saying this, he took off his hair and said, "This is a wig. My hair is falling out too fast. I thought it wouldn't be a good idea to have a bald head, so I just shaved my head and wore a wig."

Everyone knows that Chen Yuanguang can take a joke, has no concept of superiors and subordinates, and treats everyone as partners rather than subordinates.

"Mr. Xu, you are open-minded and willing to give up. Only by giving up can you gain. What you gave up is your sparse hair, and what you got is a thick head of hair." Chen Yuanguang smiled and said, "Others can follow suit.

At this year's annual meeting, everyone can collectively shave their hair to show respect after their performances. Others take off their hats while we shave our hair!"

After the jokes, Chen Yuanguang projected a rocket design on the screen:

“The design of my rocket this time is very different, first of all, it uses composite propulsion.

It will consist of two parts: an electric drive engine and a fossil fuel engine. Even for fossil fuels, we plan to use cryogenic liquid hydrogen.

We will use cryogenic liquid hydrogen and oxygen as fuel to build its thrust system.

The entire three-stage launch uses a room-temperature superconducting electromagnetic drive system in the first stage, which gives it an initial speed through a ground-based launch tower.

Then the second stage is cryogenic liquid hydrogen and oxygen, and a complete cluster of small engines is used for secondary acceleration.

For the third stage, we need to use an electric drive engine to give it a force until it enters the predetermined orbit.

Everyone knows that methane is the most mature fuel in the field of rocket engines. It achieves an excellent balance in performance, reliability and storability.

Cryogenic liquid hydrogen is quite unstable and has a relatively high risk of explosion.

I can tell you clearly that the reason we chose liquid hydrogen as fuel is that after we build a base on the moon in the future, the lunar base will decompose lunar water, and the decomposed hydrogen and oxygen can be used as fuel.

The space station and lunar base will be our transit stations for space mining. The abundant resources on the moon will undertake very important tasks.

Including helping composite rockets replenish fossil fuels.

So our fossil fuel of choice is liquid hydrogen.”

Simply put, if you are just going to the moon or Mars, methane is definitely a better fuel.

If you consider traveling back and forth between the space station and the lunar base, liquid hydrogen is undoubtedly a better choice.

It would be much easier to produce hydrogen on the lunar surface than to produce methane. Considering the temperature on the back of the moon is minus 183 degrees Celsius, it would also be much easier to cool hydrogen into liquid hydrogen and produce coolant for fossil fuels.

After listening to Chen Yuanguang's opening remarks, Lin Tianmin looked at Yang Jiashan with a take care expression, because it sounded like this was not something that could be accomplished in just one year, even for the God of Light.

If you don't bomb it more than a dozen times, you may not even get close to success.

They have never heard of any news of this type of rocket explosion, so a conservative estimate is that it will take three years to successfully develop it.

"To ensure that the liquid hydrogen does not explode, we added a carbon fiber and glass fiber reinforced polymer shell outside the engine thrust chamber and a new ceramic composite material inside it, named C1 and C2 respectively."

If Japanese car companies that bet on hydrogen energy knew that China had developed this thing, they would have to buy the preparation process of these two new materials even if they had to use a share swap. C2 is actually an optimization based on the 12K fiber of a Japanese company called Toray.

In order to purchase the 12K technology from Toray, the deal was completed by a seemingly Chinese private enterprise.

“We then added the C1 spacer in the middle of the thrust chamber, with the fuel injector and C2 rocket nozzle at the left and right ends of the chamber respectively.

You can see that the C1 spacer is a tube wrapped around a filament with longitudinal stringers because it also needs to provide a path for the coolant. The spacer helps to evenly distribute the liquid hydrogen around the C2 and prevents the C2 inner shell from moving.

The advantage of this design is that it separates the thermal load from the pressure load borne by the shell, greatly reducing the risk of hydrogen explosion.

Because everyone needs to know that if the chamber is a single shell or a monolithic shell, then it must withstand both pressure and temperature loads.

According to supercomputer calculations, the service life of this chamber will be much longer than that of traditional metal chambers, which usually fail due to heat loads. These heat loads are caused by the huge temperature differences in the system, from the low temperature of the oxidizer and fuel to the high temperature during the combustion process. Even if it uses liquid hydrogen, its life span is enough for at least 10 launches.

In addition to using C2 material on the inner shell, we also use it for transpiration cooling."

After the day's meeting was over, while eating dinner in the cafeteria, Lin Tianmin asked: "Boss, do you understand?"

Yang Jiashan shook his head: "I can only say that I roughly know the design ideas of the God of Light, but you say you understand it, but it really is not what you understand.

I guess I will have to take the materials with me when I go back and understand the meaning of each noun, as well as which rockets were designed like this in the past.

Even if there is no rocket designed like this, at least look for similar concept designs from NASA.

Otherwise I feel like I'm completely confused.

This design idea is too crazy. After listening to it, I feel that the reason why it won’t explode is entirely due to the new materials of C2.

Although many new designs are used, whether it is transpiration cooling or internal and external load separation, it is fundamentally based on trust in C2.

Before launching, I don’t know whether it will succeed or not.” Yang Jiashan felt that his brain was filled with too much content today and he needed to digest it well when he returned.

“From a thermal perspective, evaporative cooling is the most efficient cooling method, providing a continuous film of coolant where it is needed, thanks to the microporous nature of the material introduced by Guangshen. When using film cooling, an additional film layer is maintained on the chamber wall.

However, this cooling method also has a lot of problems. For example, in regenerative cooling, the heated coolant is sent to the injector head after cooling the combustion chamber, which will cause the thermal efficiency of the entire system to decrease. "Lin Tianmin said.

"That's right. It depends on your choice. According to what Guangshen just introduced, its lack of thermal efficiency can be compensated by the third-stage electric drive engine." Yang Jiashan said.

Lin Tianmin suddenly realized, "I understand, because the God of Light has been talking about the entire second-stage power system all day, so I didn't even remember that it is a composite-powered rocket.

I'm still stuck on the fact that it's a fossil fuel rocket, so I've been wondering what to do about the loss of thermal efficiency caused by transpiration cooling.

With Level 3 electric power, this problem is no longer a problem.

This is also a defect that composite propulsion can make up for, but fossil fuel rockets cannot.”

“Yes, the advantages of composite rockets are definitely huge, but along with that comes the fact that they are also extremely difficult.

Guangshen has introduced so much today, and it seems that most of the design work has been completed, but I always feel that things will not go so smoothly.

It is unrealistic to successfully launch such a groundbreaking feat in the field of space in one go.

If it didn't explode two or three times, I would have started to doubt whether we were using liquid hydrogen."

"It's good to blow it up. The God of Light won't be angry with everyone because of the rocket explosion. But it's probably unrealistic for you to return to Shenhai in the short term."

(End of this chapter)