In fact, it wasn¡¯t just Tian Changmao. Mr. Tian was shocked by the series of parameters Zhuang Jianye said. Tian Luyi next to him didn¡¯t get there either. He opened his mouth wide and couldn¡¯t say a word.
There is no way, the parameters of the dpz-2d liquid oxygen-kerosene rocket engine are too scary.
You must know that the weight of domestic liquid rocket engines of the same level is at least 1.8 tons, and usually around 2.5 tons is considered normal. A thrust-to-weight ratio of more than 60 is considered an incredible achievement, and a specific impulse of 200 seconds can qualify for national evaluation. level awards.
However, all this is not enough in front of the dpz-2d liquid oxygen-kerosene rocket engine. Except for the slightly inferior thrust, it is different from the rd-120 liquid oxygen-kerosene rocket imported from Russia by the domestic aerospace department in the early 1990s. The engines are roughly equivalent in performance.
You must know that the sea level thrust of the rd-120 liquid oxygen-kerosene rocket engine is only 74 tons, and the specific impulse is 320 seconds. It seems to exceed the dpz-2d liquid oxygen-kerosene rocket engine by a large margin in terms of data, but if Counting the total weight of the rd-120 liquid oxygen-kerosene rocket engine of 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 on the payload, and the payload is the most critical indicator in the aerospace field.
Of course, this is just one of the points. As veterans in the industry, the grandfather and grandson naturally see it more deeply than the average person.
To have such a powerful 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 from the rocket fuel tank can be poured into the combustion chamber at the fastest speed and in the most explosive way, and then mixed and burned to finally form the desired thrust.
Therefore, the greater the pressure of the gas turbine pump, the more complete the combustion of the rocket engine, and the greater the thrust provided.
And 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. If it is higher, the blades of the gas turbine pump will not be able to withstand the corrosion and erosion of the high temperature, high pressure and low-temperature fuel inside the rocket engine.
Because of this, we have entered the 21st century, and the fuel of domestic liquid launch vehicles still uses old propellants such as undimethylhydrazine and dinitrogen tetroxide that were used in the 1950s and 1960s.
Especially one of them, undimethylhydrazine, is an extremely toxic substance in itself, so that when the price of this substance is sky-high, the staff must wear protective clothing at all times.
In addition, this type of propellant combustion will cause varying degrees of pollution to the air and water, especially when the rocket debris lands. If not handled in time, it is likely to cause irreversible damage to the surrounding area.
That¡¯s all. The most important thing is the cost. Whether it is dimethylhydrazine or dinitrogen tetroxide, they are particularly scarce chemical products. Whether they are prepared or stored, money is almost always piled up step by step.
There are so many disadvantages, don¡¯t people in the domestic aerospace industry know about them?
Of course I know, but there is no way. The propellant composed of undimethylhydrazine and dinitrogen tetroxide has a high combustion value, and the pressure requirements of the gas turbine pump are not high. The manufacturing of rocket engines for this type of propellant can be easily completed in China.
If it is replaced by a liquid oxygen-kerosene rocket engine, the combustion value will be reduced by more than half, and the fuel turbine pump will need to provide greater pressure to achieve the same thrust. However, several domestic aerospace production plants do not have the production and processing capabilities for such complex products. .
Because of this, even if we know that kerosene is a cheaper fuel, leaves less residue after burning and is more environmentally friendly, we can only continue to use the previous generation propellant due to technical problems.
The same is true for similar liquid hydrogen-liquid oxygen rocket engines, which are also stuck on the core component of the high-power gas turbine pump.
In this regard, the former Soviet Union and the United States are the leaders on the entire planet. Because of their breakthroughs in related technologies, the former Soviet Union is the leader in the technical route of liquid oxygen-kerosene rocket engines. Now it has a thrust of 700 tons. The rd-170 rocket engine has almost become a special product for American liquid oxygen-kerosene launch vehicles.
The United States¡¯ own RS-25 liquid hydrogen-liquid oxygen rocket engine developed all the way from the space shuttle and has now become the main power of the Delta series of heavy-duty launch vehicles and the main force in the United States¡¯ conquest of the stars and the sea.
?? Whether it¡¯s Europe, Japan, or China, the gap between them and these two countries is really not even a tiny bit.
To be more precise, if the disintegration of the Soviet Union had not resulted in the spillover of a large number of aerospace technologies, it is hard to say whether places in Europe would have been able to launch something large with a carrying capacity of more than 10 tons in low-Earth orbit.
But thenEven if the aerospace technology of the former Soviet Union spilled over, no one could fully master the high-performance liquid oxygen-kerosene rocket engine technology, especially the high-power gas turbine pump. In the early 1990s, some people in Russia took advantage of the country's chaos. Take this thing out and exchange it for money.
There are a lot of people buying it, but outside of the United States, even if you get the drawings and parameters, you still can¡¯t make it with half a piece of wool.
This is like a bad student taking the answers of a top student but still failing to pass the test paper. It¡¯s not that the bad student doesn¡¯t work hard, it¡¯s because the top student¡¯s teachings are too profound.
¡°Just imagine how many years the Soviet Union has been researching liquid launch vehicle missiles, and how long other talents have been struggling.
If nothing else, the former Soviet Union's SS-18 "Satan" super-heavy ballistic missile is a typical liquid-fuel ballistic missile, and the R-29 series submarine-launched ballistic missiles equipped by the Soviet Navy are also liquid-fuel configured.
It is no exaggeration to say that the Soviets have already mastered liquid fuel, and the related rocket engines are naturally not an issue.
Therefore, without the strong materials science, fluid mechanics, production technology, and manufacturing experience of the Soviet Union, even if there are drawings and experts, they are just imitating others.
So whether it¡¯s Europe, Persia, or South Korea, after some research, you have no choice but to pay for original products from Russia.
The country is no exception. Taking advantage of the disintegration of the Soviet Union, the country obtained several samples and some technical data of the rd-120 liquid oxygen-kerosene rocket engine. However, after some dismantling and research, it was found that even the old Maozi in the 1960s and 1970s The product could not be copied based on the domestic technical level at that time.
Regardless of anything else, the aerospace experts at the time were confused as to what the dark gray coating on the gas turbine pump on the rd-120 was. In the end, they could only study the samples carefully while spending a lot of money to introduce Russian products.
It was precisely because of such an unforgettable experience that Tian Changmao was shocked by the DPZ-2D liquid oxygen-kerosene rocket engine on TV. He felt unbelievable and unbelievable.
Just when Tian Changmao was thinking about how Zhuang Jianye did it, Tian Luyi, who had been opening his mouth in surprise, shouted like a corpse: "I know it's an engine, an aero engine a gas turbine Yes, that's right, this is how the technical barriers of aviation and aerospace are clearedGrandpa~~~Grandpa~~~What's wrong with you? Don't scare me~~~"
If you like Soar My Aviation Age, please collect it: Soar My Aviation Age is updated the fastest. (Remember the website address: www.hlnovel.com