Technological Hegemony

Luo Jia explained to the general on the phone that the ultimate test of the space program is the cost performance, to see who can deliver goods to space at a lower price.

The Russian RD-171 engine, while creating history in thrust, has also reached a record high cost, which is exactly the characteristic of Mao Zihao's great success.

And Luo Jia is a man of science and technology, a believer in dataism who pays attention to seeking truth from facts. Under his leadership, the rockets of Xingchen Technology are designed according to the needs. The rocket engine is designed as much as it needs.

Besides, Luo Jia has the habit of hiding his hands in everything, and this time is probably no exception. No one can guarantee that there are no amazing secrets hidden in the design of the Xingchen rocket engine.

For Luo Jia, Russia's Yenisei super-heavy rocket has only one function, and that is to act as cannon fodder to attract real opponents to this space race, thereby quickly consuming the opponent's strength.

...

A subsidiary of Star Technology, Rocket Lab.

Luo Jia has been in the rocket laboratory for several months, and all the plans are advancing at an extremely fast speed. It seems that everything is moving in the right direction, and the only exception is the injection combustion system.

For several days, the Rocket Lab was full of gloom and mist, and everyone seemed to be under a lot of pressure. Luo Jia's office was filled with whiteboards, with secret and extremely complicated formulas and numbers written on the whiteboards.

Except for taking a shower and going to the toilet, Luo Jia almost never leaves the office. He is like a high-speed machine, working crazily and continuously with high intensity.

This state of his made everyone in the lab nervous. After all, Luo Jia was the leader of the Tough Guys. If something went wrong with him, it would be an irreparable loss for the entire company and even China.

So everyone discussed and invited Vice President An Ran, hoping that An Ran could persuade Luo Jia, but they were surprised to find that An Ran, like Luo Jia, was also a lunatic!

For forty-eight hours, the two of them stayed in the office, discussing and analyzing constantly. They are rare geniuses in the world, and their brains think at an extremely fast speed.

Everyone was dumbfounded when they heard An Ran and Luo Jia arguing in the office. The two were jumping back and forth in different disciplines. They were still discussing thermodynamics just now, but they jumped to aerodynamics in the blink of an eye.

In short, it means that it is a waste of the brain. It is okay to follow their thinking for a few minutes. If it exceeds fifteen minutes, the brain will become chaotic. If it exceeds half an hour, the headache will be splitting. If it reaches an hour, it is hell and it will drive people crazy.

So,

The matter changed from Luo Jia being alone, to him and An Ran...

An Ran stayed in the Rocket Lab, and the leaders of the major project teams in the hardware department quit, complaining about the colleagues in the Rocket Lab, why did An Ran persuade Luo Jia? Anyone who is familiar with Mr. Luo knows that he never listens to persuasion.

In short, the colleagues at Rocket Lab finally realized that there was a reason why Luo Jia and An Ran were able to stand at the top of the company. They were not only smarter than most people, but also worked harder!

Is the injection combustion system really that important for a rocket to allow two bosses to work non-stop?

The answer is yes.

As rocket fuels continue to be updated, keeping the injection system stable is becoming more and more difficult.

Not to mention the latest generation of liquid oxygen methane engines, even the previous generation of liquid oxygen and liquid hydrogen engines has also brought huge troubles to scientists. Luo Jia intends to save costs to the utmost and allow the engines to be reused infinitely. In this way, for The requirements for durability and stability are even higher.

"Next, continue to improve your ideas. I'm going back. After all, the hardware department is also busy, and I don't have time to stay with you for a long time." An Ran scratched her hair that had already turned into a chicken coop, and said to Luo Jia.

"Understood, don't just focus on your work, spend more time with your wife and children when you have time, and don't worry about not knowing you as a father in the end." Luo Jia teased.

"Come on." An Ran waved her hand disapprovingly, "You are a bachelor, but you have taught me a lesson on being a father? Let's talk about it when you have a wife and children."

What does this have to do with being single?

His meow single dog really has no human rights. He said good things, but no one would listen.

Luo Jia shook his head and muttered in his heart.

...

The reason was unclear, and the in-depth discussion with An Ran made Luo Jia change his mind. He wiped all the whiteboards in the office and started from the beginning. Soon, the numbers and formulas on the blank whiteboards were dense again.

He is calculating TR instability, which is Taylor instability, the interface between two fluids with different densities is unstable. In the gravitational field, when the heavier fluid is on top of the lighter fluid, the instability may occur .

During jet injection of a rocket engine, the acceleration causes cavitation of the propellant in the pipeline, and the bubbles after cavitation will induce compressible Taylor instability.

In addition, the high-speed flow of the propellant in the centrifugal pump and the pipeline will also cause cavitation. The bubbles generated by the cavitation will release the pressure at the moment of jet injection. If the centrifugal pump has cavitation in the working state, it will be fatal. must be completely eliminated.

In addition to Taylor instability, rocket injection devices must also take into account RM instability, that is, turbulent flow instability.

Regardless of the tangential velocity gradient or the normal acceleration, disturbance waves will be generated on the fluid interface in essence. A small amount of disturbance waves propagate at supersonic speed and become shock waves. The trough will produce a speed difference and promote the evolution of disturbance, which will eventually cause turbulence and bring huge hidden dangers.

In short, the rocket engine is extremely difficult to design, and a low-cost engine with stable performance that can be used repeatedly for a long time, the design difficulty is not a huge problem, but the difficulty is against the sky!

For example, during the fuel injection process of a rocket engine, the atomized medium is regenerated and cooled by the nozzle wall, becomes gas and then ejected from the nozzle. At this time, the injection velocity often interacts with the supersonic speed and velocity oscillation, which inevitably brings shock waves. It will even be superimposed with the interference brought by the expansion wave.

For another example, in free space, the pressure disturbance caused by the shock wave and combustion will diffuse freely into the environment. In a nearly closed acoustic cavity such as the combustion chamber, the shock wave and pressure wave will definitely refract when encountering the engine wall. And this often leads to unstable high-frequency combustion.

Anyway, there are too many factors that can cause instability. The aerospace industry has gathered the most intelligent brains in the world, but disasters still happen one after another. It can be seen that the most difficult thing about rockets is not to make them, but to actually achieve them. Stability and security, this is something that even the most experienced North America and Russia cannot do.

The numbers and formulas became more and more complicated, and they were gradually simplified in the next few days. In the end, there was only a large whiteboard left in the office, on which was written the results obtained by Luo Jia in the past ten days. The name of this result called.

Coaxial jet injection system!