Ten days after the satellite project was launched, at 23 o'clock in the evening, Zhou Ruicai walked out of the school gate with a tired body.

He didn't look like a senior professor at all, he sat casually at a roadside stall, ordered fried pho, and ate it with hulala.

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

Zhou Rui only ate a few bites with his head down, and suddenly was patted on the back.

"Yo, Professor Zhou is going to marry a little daughter-in-law to earn a bride price, and he will deal with it like this at night?"

"Tang Weitian!"

Zhou Rui looked at the old man in front of him who was wearing trousers and shirts and had white hair combed meticulously, and sat down at the greasy table without care.

Tang Weitian, who was just named an academician of the Academy of Sciences last year, is a professor at Southwestern Polytechnical University, that is, the 985 school that cooperates with the Southern Institute of Mechanical Engineering to develop satellites.

The two were high school classmates and worked together for more than a year, and their friendship was very deep.

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

first chatted about the old feelings of his classmates, and then asked about the recent situation of his family, and Tang Wei asked the real purpose.

"Lao Zhou, I recently came to Shuchuan to attend a meeting, I heard that you are amazing, you want to build satellites and rockets?"

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

Tang Weitian's eyes lit up when he heard this, especially when he heard that the rocket was made by a private enterprise himself, he couldn't sit still, and deliberately pretended not to believe it:

"The country has just opened up the aerospace market, and he made it at a young age? And saying that launching rockets in a month won't be a fraud of your funds, right? ”

This trick really worked, and it poked the hope of Zhou Rui for most of his life, and he immediately became anxious:

"Liar? The chief engineer is the backbone of Aramco Aerospace! It has only been a long time before the prototype of a first-stage rocket engine and a 120-ton kerosene machine has been built.

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

"Go, why don't you go!"

Watching Tang Weitian fight the snake and then Zhou Rui felt that he had been fooled, but he couldn't take back what he said, so he admitted it.

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

Also produced by the system, this test bench is a two-station test, which can test two engines at the same time, and can withstand a maximum thrust of 250 tons, which is already very large.

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

"This prototype is made by a few masters while I am training workers, and the internal name is K120, K is the English initials of kerosene, and 120 is 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, which is not complicated even if it is semi-artificially manufactured, and 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 you want to install 7 units...... Not 9 of these engines, one in the middle, and eight around the design, what is the diameter of the arrow body? ”

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

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

Lin Ju smiled, he thought of the Falcon 9 rocket and the heavy Falcon that the empty fork would succeed in a few years, anyway, their thinking had been proven right, and there was no shame in adhering to the doctrine of taking.

"If you have one engine in the middle, you only need to start one engine in the middle when you are vertically recycling, which is convenient for fuel saving."

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

Guo Shen was a little surprised, at this time, Lao Ma's empty fork was still setting off fireworks, both laymen and insiders did not believe that he could succeed, and even Lao Ma himself was blown up a little unconfident.

"I can't see it, Boss Lin's aerospace ideas are also very advanced."

An unfamiliar voice sounded, and Lin Ju wanted to see who was eavesdropping, so he saw Tang Weitian walking out with a smile.

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

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

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

"Where, Mr. Zhou is serious, it's my honor for Academician Tang to come over."

"It doesn't matter, I'm just going to take a look, I just heard you say that you want to have 9 engines in parallel in one stage, so many words are too risky, 5 to 7 are very suitable, and a capacity of 15 to 20 tons is already a big rocket.

Don't call me an academician, just call out to the teacher. ”

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

"Since you asked me to call me Mr. Tang, then just call me by my name, but do you know that there is another reason why I asked 9?"

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

Lin Ju became proud, only to see that his left and right hands held a circle, and gently moved closer to the middle.

"With the design of 9 engines in the core stage, and then using the CBC configuration to use the core stage as a booster, the total thrust will exceed 3,000 tons, and the carrying capacity of low earth orbit will be close to 100 tons.

And this carrying capacity ......"

"Moonshot!"

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 thrust of 3,400 tons in the first stage and a carrying capacity of more than 110 tons in low earth orbit.

With current technology, the moon landing spacecraft will definitely be able to reduce a lot of weight, and 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, and Lin Ju's words made him see the new direction of astronautics.

The CBC configuration greatly simplifies rocket design, as the booster is identical to the main rocket stage and is easier to produce.

But he immediately calmed down again:

"It's a very clever idea, really, indeed, 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, and a bad one is troublesome, and the fault tolerance rate is too low, which is not only the control system, but also the requirements for the engine. ”

"But it's because it's difficult that we have to do it, only in this way can we reduce the cost of rockets, and if we use recycling technology, even if we can only recycle it ten times, the price of space cargo will drop to an extremely terrifying level.

The future of aerospace must be cheap, as long as you follow this path, you will not be wrong. Now that electronic technology is so advanced, one day it will be able to achieve this ability. ”

Lin Ju already knows that at the end of next year, the Falcon 9 with the same level of 9 engines will be successfully recovered, and the next one will be a smooth journey, so the road will not only be through, but also not far.

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

At this point, the test bench was ready, and as the announcer cleared the field, the people inside the console began to fill the engine with fuel.

“10，9，8…… 3, 2, 1, ignition. ”

Looking through the window, there was a series of white smoke from the engine nozzle, which was liquid oxygen that had escaped 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 ejected tail flame grows longer and longer until the throttle valve is maximum.

The air flow of 120 tons of thrust hit the ground, and the roar and vibration were felt for several kilometers.

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

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

The sound of the radio sounded, and there was a round of applause in the observation room, and the workers involved in the engine manufacturing were happy and at the same time felt a little confused.

"Third child, didn't you say that we built rainfall equipment? Why is this still breathing fire? I look like a rocket engine on TV. ”

"I ...... I don't know! ”