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

Russia's RD-171 engine, while the thrust has created history, the cost has also reached a record high, which is in line with the characteristics of Maozi's great success.

Under his leadership, Xingchen Technology's rockets are designed in full accordance with the needs, and the rocket engine is designed as much thrust as it needs.

Besides, Luo Jia has the habit of hiding one hand in everything, and I'm afraid this time will not be an exception, no one can guarantee that there is no amazing secret hidden in the design of the Xingchen rocket engine.

For Luo Jia, Russia's Yenisei Super Heavy rocket has only one function, that is, to be cannon fodder, to attract real opponents to this space race, so as to quickly consume the opponent's strength.

……

Rocket Laboratory, a subsidiary of Xingchen Technology.

Luo Jia has been in charge of Rocket Lab for months, and all plans are moving forward at breakneck speed, and everything seems to be moving in the right direction, with the only exception being the injection combustion system.

For several days, the rocket lab was full of gloomy clouds, everyone seemed to be under a lot of pressure, and Luo Jia's office was full of whiteboards, on which were written secret numbness, extremely complex formulas and numbers.

Except for bathing and going to the toilet, Luo Jia almost never leaves the office, he is like a high-speed machine, crazy and continuous high-intensity work.

His state made everyone in the laboratory nervous, after all, Luo Jia was the head of the tough guy Tiantuan, if something happened to him, it would be an irreparable loss for the whole company and even the entire Huaxia.

So everyone discussed it 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 madman!

For forty-eight hours, the two of them stayed in the office, constantly discussing and analyzing, they were rare geniuses in the world, and their brains were thinking extremely fast.

Everyone listened to An Ran and Luo Jia arguing in the office, they were all stupid, the two of them were jumping back and forth in different disciplines, and they were still discussing thermodynamics just now, and they jumped to aerodynamics in the blink of an eye.

In short, it means to spend your brain, it's okay to follow their thinking for a few minutes, but after fifteen minutes, the brain will become chaotic, more than half an hour, with a splitting headache, up to an hour, that's hell, and it will drive people crazy.

As a result, things changed from Luo Jia's liver explosion alone, to him and An Ran...

An Ran stayed in the rocket lab, and the heads of the major project teams in the hardware department stopped working, complaining about the colleagues in the rocket lab, why did An Ran persuade Luo Jia? Those who are familiar with Mr. Luo know that he has never listened to persuasion.

In short, the colleagues of Rocket Lab finally realized that there is a reason why Luo Jia and Enron can stand at the top of the company, they are not only smarter than most people, but also more desperate!

Can the two CEOs work tirelessly, is the injection combustion system really that important for a rocket?

The answer is yes.

As rocket fuel continues to evolve, keeping the injection system stable is becoming more and more difficult.

Not to mention the latest generation of liquid oxygen methane engines, that is, the previous generation of liquid oxygen and liquid hydrogen engines, which also brought huge trouble to scientists, Luo Jia intends to save costs to the limit and let the engine be reused indefinitely, so that the requirements for durability and stability are higher.

"Next, you continue to refine your thinking, I'm going back, after all, the hardware department is also busy flying, and I don't have time to accompany you for a long time." An Ran scratched his hair, which had long been turned into a chicken nest, and said to Luo Jia.

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

"Come on." An Ran waved his hand disapplausively, "You bachelor, but you have taught me a lesson as a father?" Let's wait until you have a wife and children. ”

What does this have to do with being single?

His meow's single dog really has no human rights, and what he says is obviously good, but no one is willing to listen.

Luo Jia shook her head and muttered in her heart.

……

The reason is not clear, and the in-depth discussion with An Ran made Luo Jia change his mind, he wiped all the whiteboards in the office clean, and started from scratch, and soon, on the blank whiteboard, the numbers and formulas were densely packed again.

He was calculating TRinstability, or Taylor instability, the instability of the interface between two fluids of different densities, which can occur in a gravitational field when a heavier fluid is above a lighter fluid.

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

In addition, the propellant flows at high speed in the centrifugal pump and pipeline, and cavitation will also occur, and the bubbles produced by the cavitation will release the pressure at the moment of jet ejection.

In addition to Taylor instability, the rocket ejector must also take into account RMinstability, or turbulent instability.

Regardless of tangential velocity gradient or normal acceleration, the essence will produce disturbance waves on the fluid interface, and a small number of disturbance waves propagate at supersonic speed to become shock waves.

In short, the rocket engine is extremely difficult to design, and a low-cost engine with outrageous stable performance and can be used repeatedly for a long time is not a great problem, but a difficult one!

For example, in the process of fuel injection of a rocket engine, the atomized medium is regenerated and cooled through the nozzle wall, turning into gas and then spraying out of the nozzle, and the injection velocity at this time often interacts with the speed of sound and velocity oscillation, which inevitably brings shock waves, and even superimposes with the interference caused by expansion waves.

For example, in free space, the pressure disturbance caused by shock wave and combustion will spread freely into the environment, and in a nearly closed acoustic cavity such as the combustion chamber, the shock wave and pressure wave will encounter the engine wall and will be refracted again, which will often lead to high-frequency combustion instability.

Anyway, there are too many factors that will cause instability, the aerospace industry has gathered the world's smartest brains, but disasters are still happening one after another, so it can be seen that the most difficult thing about rockets is not to build it, but to truly achieve stability and security, which even the most experienced North America and Russia can't do.

The numbers and formulas became more and more complicated, and gradually simplified in the following days, and finally there was only a large whiteboard left in the office, on which was written the results of Luo Jia's liver explosion in the past ten days, and the name of this result was.

Coaxial Jet Injection System!