I ask you to build tractors, but you build rockets?

Ten days after the satellite project was launched, at 23:00 in the evening, Zhou Ruicai walked out of the school exhausted.

He no longer looked like the senior professor he used to be. He sat casually at a roadside stall, ordered fried rice noodles, and started eating.

In the eyes of people on the roadside, this little old man is no different from a migrant worker.

Zhou Rui buried his head and took a few mouthfuls, when suddenly he was patted on the back.

"Hey, Professor Zhou wants to marry his daughter-in-law to earn a bride price, and you just deal with it like this tonight?"

"Tang Weitian!"

Zhou Rui looked at the old man in front of him who was wearing trousers and a shirt, with his white hair combed meticulously, and he was sitting in front of the greasy table without caring.

Tang Weitian, who was just elected as an academician of the Academy of Sciences last year, is a professor at Southwest Polytechnic University, which is the 985 school that cooperates with Nanjing Institute of Technology to develop satellites.

The two are high school classmates and have worked together for more than a year, and their friendship is very deep.

At this time, he was very happy to see his old friend Zhou Rui and wanted to take him to a restaurant. However, Tang Weitian just ordered a bowl of rice noodles and ate it with relish at the roadside stall.

After first chatting about old classmates and asking about the current situation of his family, Tang Wei finally asked about the real purpose.

"Old Zhou, I recently came to Sichuan to attend a meeting. I heard that you guys are really serious. Are you going to develop satellites and rockets?"

Although he had known for a long time that his old friends would not look for him for no reason, Zhou Rui was still very happy, and since it was not a secret, he told the whole story.

Tang Weitian's eyes lit up when he heard this. Especially when he heard that the rocket was actually built by a private enterprise, he couldn't sit still. He deliberately pretended not to believe it:

"The country has just opened up the aerospace market, and he built it at a young age? He also said he would launch a rocket in one month. Isn't he trying to defraud you of your funds?"

This trick really worked, and it stoked Zhou Rui's hopes for most of his life. He immediately became anxious:

"Liar? The chief engineer is the backbone of the Aramco Space Agency! In just a short time, the first-stage rocket engine and the 120-ton kerosene engine prototype have been built.

I happen to have a day off tomorrow morning, will you go? "

"Go, why don't you go!"

Watching Tang Weitian beat the snake and follow Zhou Rui, he felt that he had been fooled, but he couldn't take back what he said, so he had to admit it.

The next day, he and Tang Weitian took a car to the test bench on the hill across from the tractor factory.

Also produced by System, this test bench has a dual station and can test two engines at the same time. It can withstand a maximum thrust of 250 tons, which is quite large.

When they arrived, the engine was ready and the electrical system was self-checking. Guo Shen was introducing it to Lin Ju.

"This prototype machine was made by several masters while I was training workers. The internal name is K120. K is the English initials of kerosene, and 120 is the thrust.

The K120 is a simple and efficient engine, weighing 1.2 tons, with a single combustion chamber and a maximum diameter of 1.3 meters. Even semi-manual manufacturing is not complicated. It only takes 168 hours to produce the next official version, which is very efficient. "

Lin Ju was very satisfied with this data, and suddenly thought of something and asked:

"If we want to install 7... or 9 engines of this kind, with one in the middle and eight engines on the sides, what is the diameter of the rocket body?"

Guo Shen thought about the following, drew a few circles on the table with a ballpoint pen, thought about the layout, and quickly gave the answer:

"Six meters, maybe. Do you want to build a big rocket? In this case, the thrust will be 1,000 tons, and the near-earth transport capacity will be almost 30 tons. But why put one in the middle? If you put three in the middle, the structure will have a larger gap and be safer. .”

Lin Ju smiled. He thought of the Falcon 9 rocket and Falcon Heavy that would be successful in a few years. In any case, their ideas have been proven to be right, and there is no shame in adhering to the principle of appropriation.

"If there is one in the middle, you only need to start the engine in the middle during vertical recovery. It saves fuel and is convenient."

"Do you believe Ma Yilong's recycling theory?"

Guo Shen was a little surprised. At this time, Lao Ma's empty fork continued to set off fireworks. No matter the layman or insiders, they didn't believe that he could succeed. Even Lao Ma himself was a little unconfident.

"I can't tell that Boss Lin's aerospace ideas are also very advanced."

A strange voice sounded. Lin Ju wanted to see who was eavesdropping, and saw Tang Weitian walking out with a smile.

"Lin Ju, this is my old classmate and an academician of the Academy of Sciences, Tang Weitian. I heard that you are working on rockets and I had to come and have a look.

I brought him here without permission, please don't blame me. "

Zhou Rui was still a little embarrassed, but Lin Ju immediately became excited when he heard that he was an academician.

"No, no, Teacher Zhou is serious. It's my honor for Academician Tang to come over."

"It doesn't matter, I'm just taking a look. I just heard you say you need to connect 9 engines in parallel in one stage. It's too risky to add so many engines. 5 to 7 engines are suitable. One with a transport capacity of 15 to 20 tons is already a big rocket. .

Don't call me academician, just call me teacher. "

Tang Weitian's elder-like attitude made Lin Ju feel very comfortable, but as a time traveler, he was still a little unconvinced.

"Since you asked me to call you Teacher Tang, just call me by my first name. But do you know there is another reason why I asked Channel 9?"

"Oh? It seems that classmate Lin Ju has other ideas? Let's talk about it."

Lin Ju became proud and saw that he held a round shape with his left and right hands and gently moved closer to the middle.

“Using a design of nine engines in the core stage, and then using the CBC configuration to use the core stage as a boost, the total thrust will exceed 3,000 tons, and the low-Earth orbit carrying capacity will be close to 100 tons.

And this carrying capacity..."

"Moon landing!"

Guo Shen, Zhou Rui, and Tang Weitian said these two words at the same time.

The Saturn V rocket used by Aramco to land on the moon in the last century has a first stage of 3,400 tons of thrust and a low-Earth orbit carrying capacity of more than 110 tons.

With current technology, the moon landing spacecraft can definitely lose a lot of weight. If it can send a 100-ton spacecraft into space, it will definitely fly to the moon with three astronauts.

Tang Weitian was very excited. Lin Ju's words made him see the new direction of aerospace.

The CBC configuration can greatly simplify rocket design because the booster is exactly the same as the main rocket first stage and is easier to produce.

But he immediately calmed down again:

“The idea is really, really clever, but it’s too difficult to control multiple engines, there are too many engines.

There are a total of 27 engines in the three core stages. If one of them fails, it will be troublesome. The fault tolerance rate is too low. Not only the control system, but also the requirements for the engine are also very high. "

"But we have to do it because it is difficult. Only in this way can the cost of the rocket be reduced. If recycling technology is used again, even if it can only be recycled ten times, the price of aerospace cargo will drop to an extremely terrifying level.

The future of aerospace must be cheap, and as long as we follow this path, we will not go wrong. Nowadays, electronic technology is so advanced that one day it will be able to achieve this capability. "

Lin Ju already knows that the Falcon 9 with the same first stage and nine engines will be successfully recovered at the end of next year. It will be a smooth journey from now on, so the road is not only open, but also not far away.

However, in the eyes of the three people, Lin Ju is the confidence of young people, but his statement is indeed very reasonable, and it is more emotional.

The test bench was now ready, and as the announcer cleared the stage, the people in the console began to inject fuel into the engine.

"10, 9, 8...3, 2, 1, ignite."

Looking out the window, white smoke appeared repeatedly from the engine nozzle, which was liquid oxygen escaping into the air.

Fuel is then pumped into the combustion chamber and the nozzle begins to release flames.

The engine's throttle valve slowly opens, the thrust slowly increases, and the tail flame emitted becomes longer and longer until the throttle valve reaches its maximum value.

The airflow with a thrust of 120 tons hits the ground, and the roar and vibration can be felt for several kilometers.

Therefore, in order not to affect the machining accuracy of the machine tool, it was moved so far away.

"The current thrust is 122.3 tons, and the throttle valve is open 100%!"

The broadcast sounded, and there was applause in the observation room. The employees involved in engine manufacturing were happy, but at the same time felt a little confused.

"Third brother, didn't you say that we built a rainfall device? Why does it breathe fire? It looks like a rocket engine on TV."

"I...I don't know either!"