Chapter 1540

In fact, it wasn't just Tian Changmao. Old man Tian was surprised by a series of parameters said by Zhuang Jianye. The nearby Tianlu didn't get there. He opened his mouth and couldn't say a word.

I can't help it. The parameters of dpz-2d liquid oxygen kerosene rocket engine are too scary.

You should know that the weight of the domestic liquid rocket engine of the same level should be at least 1.8 tons, which is usually about 2.5 tons. If the thrust weight ratio can reach more than 60, it is a great achievement. If the specific impulse can reach 200 seconds, you can participate in the National Award.

However, all this is not enough in front of the dpz-2d liquid oxygen kerosene rocket engine. In addition to the slight difference in thrust, the performance is roughly equivalent to that of the rd-120 liquid oxygen kerosene rocket engine imported from Russia by the domestic aerospace department in the early 1990s.

You should know that the sea-level thrust of rd-120 liquid oxygen kerosene rocket engine is only 74 tons, with a specific impulse of 320 seconds, which seems to exceed the data of dpz-2d liquid oxygen kerosene rocket engine by a large part. However, if the total weight of rd-120 liquid oxygen kerosene rocket engine is 3.4 tons, the excess thrust and specific impulse are really nothing.

After all, the benefits of a lighter rocket engine can be directly reflected in the load, and the load is the most key indicator in the aerospace field.

Of course, this is only one of the points. As senior people in the industry, the grandsons and grandsons naturally see it deeper than ordinary people.

To have such a strong thrust to weight ratio, the size of the rocket engine is not the key. The key is that the power of the core gas turbine pump must be large.

In this way, the fuel in the rocket fuel tank can be injected into the combustion chamber at the fastest speed and in the most explosive way, then mixed and burned, and finally form the desired thrust.

Therefore, the greater the pressure of the gas turbine pump, the more sufficient the combustion of the rocket engine and the greater the thrust provided.

If you want to increase the pressure of the gas turbine pump, you must increase the power of the gas turbine pump.

Usually, the ultimate domestic level in this regard is about 15 MPa. No matter how high, the blades of the gas turbine pump can not withstand the corrosion of high temperature, high pressure and low-temperature fuel inside the rocket engine.

Because of this, it has entered the 21st century. The fuel of domestic liquid launch vehicles still uses old propellants such as unsymmetrical dimethylhydrazine and nitrogen tetroxide, which have been used since the 1950s and 1960s.

In particular, unsymmetrical dimethylhydrazine itself is a very strong toxic substance, so that when the price of this substance is sky high, the staff must wear protective clothing all the time.

In addition, the combustion of this kind of propellant will cause varying degrees of pollution to air and water. Especially when the rocket debris lands, if it is not handled in time, it is likely to cause irreversible damage to the surrounding areas.

That's all. The most important thing is the cost. Whether it's unsymmetrical dimethylhydrazine or nitrous oxide, they are particularly scarce chemical products. Almost all of them are piled up with money step by step, whether they are prepared or stored.

There are so many disadvantages, don't people in the domestic aerospace industry know?

Of course, I know, but I can't help it. The propellant composed of unsymmetrical dimethylhydrazine and nitrous oxide has high combustion value, and the pressure requirements of the most gas turbine pump are not high. The rocket engine manufacturing of this kind of propellant can be easily completed in China.

If the liquid oxygen kerosene rocket engine is replaced, because the combustion value is reduced by more than half, the fuel turbine pump needs to provide greater pressure to achieve the same thrust. However, several domestic aerospace manufacturers do not have the production and processing capacity of such complex products.

Because of this, even if we know that kerosene is cheaper, less residue after combustion and more environmentally friendly, we can only continue to use the previous generation of propellant because of technical problems.

Similar liquid hydrogen and liquid oxygen rocket engines are also stuck in the core component of high-power gas turbine pump.

In this regard, the former Soviet Union and the United States are the leaders on the whole planet. The former Soviet Union has made a breakthrough in relevant technologies, and it can be said that the former Soviet Union has won the first place in the technical route of liquid oxygen kerosene rocket engine. Now the RD-170 rocket engine with a thrust of 700 tons has almost become a special product of liquid oxygen kerosene launch vehicle of the United States.

The United States' own rs-25 liquid hydrogen liquid oxygen rocket engine has developed all the way from the space shuttle. Now it has become the main force of delta series heavy launch vehicles and the main force for the United States to conquer the sea of stars.

The gap between Europe, Japan and China is really not a star and a half compared with these two countries.

More precisely, if the disintegration of the Soviet Union had not led to a large number of space technology spillovers, it would be hard to say whether these places in Europe would be able to launch big guys with a low earth orbit carrying capacity of more than 10 tons.

However, even if the space technology of the former Soviet Union spilled over, no one could fully master the technology of high-performance liquid oxygen kerosene rocket engine, especially the high-power gas turbine pump. In the early 1990s, some people in Russia took advantage of the national chaos and didn't take this thing out for money.

There are many buyers, but outside the United States, even if you get the drawings and parameters, you can't make half of the wool.

This is like learning slag holding Xueba's answer and failing to copy the passing test paper. It's not that Xueba doesn't work hard, but Xueba's Taoism is too profound.

Imagine how many years the Soviet Union has studied liquid launch vehicle missiles and how long other talents have been tossing about.

Among other things, the SS-18 "Satan" super heavy ballistic missile of the former Soviet Union is a typical liquid fuel ballistic missile, and the r-29 series submarine launched ballistic missile equipped by the Soviet Navy is also equipped with liquid fuel.

It is no exaggeration to say that the Soviets have spent liquid fuel, and the relevant rocket engines are of course nothing.

Therefore, without the strong material science, fluid mechanics, production technology and manufacturing experience of the Soviet Union, even if there are drawings and experts, it is also an imitation.

Therefore, no matter Europe, Persia or South Korea, after some research, they finally have to pay for the original Russian goods.

China is no exception. Taking advantage of the disintegration of the Soviet Union, China obtained samples and some technical data of several rd-120 liquid oxygen kerosene rocket engines. After some research, it was found that even Lao maozi's products in the 1960s and 1970s could not be imitated according to the domestic technical level at that time.

No matter what the dark gray coating on the gas turbine pump on rd-120 was, the aerospace experts at that time were confused. Finally, they had to carefully study the samples and spend a lot of money to introduce Russian products.

It was with such an unforgettable experience that Tian Changmao was shocked by the dpz-2d liquid oxygen kerosene rocket engine on TV. He just felt incredible and incredible.

Just when Tian Changmao thought about what Zhuang Jianye was going to do, Tian Lu, who was always surprised and opened his mouth, shouted like a corpse: "I know... It's an engine, an aeroengine... A gas turbine... Yes, that's right. The technical level of aviation and aerospace was opened... Grandpa ~ ~ ~ grandpa ~ ~ ~ what's the matter with you? Don't scare me ~ ~"