More than half an hour later, the test results of the experimental samples came out.
"Li Suo, there is no change."
"Continue to increase the pressure test." Li Xiang was not discouraged. After all, scientific experiments cannot be completed overnight.
The experiments in the laboratory continued, while Huang Haojie was thinking about something.
The sizzling sound filled the entire laboratory. As the pressure increased, the noise generated became louder and louder, and people in the laboratory had to wear earplugs.
More than three hours later.
"The good news from Li is that the solid-state maintenance temperature of submetallic oxygen has increased."
"How much has it improved?"
"Raised to minus 41 degrees Celsius."
"How long can it be stored if the temperature is exceeded?" Huang Junjie asked another question.
"It can last for about 16 minutes within the range of minus 41 degrees Celsius and below 22 degrees Celsius." The researcher replied with admiration.
Their research institute had been working on it for several months without a clue. Huang Haojie broke the deadlock as soon as he came and had to let them worship him.
"If we add more pressure, I have a hunch that success is beckoning to us." Li Xiang ordered.
"OK."
The laboratory is busy again.
Huang Junjie looked at the situation of their experiment and realized that it might be impossible to complete it for a while, so he waved to Li Xiang.
He typed on the display screen of the holographic bracelet: "You guys go ahead, I'll go to other research institutes to check, and if there are any results, I'll call you Panda."
Li Xiang made an OK gesture.
…
After leaving the noisy Materials Research Institute, Huang Haojie rode an electric car to the Hydrogen and Oxygen Motive Research Institute.
Looking out the car window, there are red maples and kapok trees. Before I know it, another year has passed.
With the expansion of Galaxy Technology, the scale of each research institute has also expanded. Now throughout Shanmei, there are either Galaxy Technology factories or research institutes.
The Hydrogen and Oxygen Motive Research Institute he is going to is located near Zhelang Town in Red Bay, more than 20 kilometers away from the Materials Research Institute.
Galaxy Technology's Hydrogen and Oxygen Motive Research Institute was established very late, and was only established in November last year.
Of course, in the face of the wealthy Galaxy Technology, the scientific research strength of the Hydrogen and Oxygen Motive Research Institute is now very good, and a large number of researchers from Dongdao have been added to it.
They are currently working on issues related to hydrogen-oxygen motive power.
Huang Junjie was looking at the situation at the Hydrogen and Oxygen Motive Research Institute.
In fact, the current motivations of space agencies or companies in various countries are different.
The engines of space rockets can generally be divided into: solid fuel rockets, liquid oxygen and kerosene engines, liquid hydrogen and liquid oxygen engines, liquid oxygen and methane engines, and dinitrogen tetroxide/hydrazine engines.
The advantage of solid fuel is that it is easy to store and shoot; the disadvantage is that the fuel is expensive and has a small specific impulse (a small specific impulse means a small load).
The advantages of the liquid oxygen kerosene engine are high cost performance and high specific impulse; the disadvantage is also very obvious. The combustion chamber is easy to sinter, which is not conducive to the repeated use of the rocket engine.
The advantages of the liquid oxygen and liquid hydrogen engine are large thrust and high specific impulse; the disadvantage is that the storage of liquid hydrogen is difficult and the production cost is high.
In addition, liquid hydrogen causes many engineering difficulties due to its low temperature. If liquid hydrogen encounters air in the pipeline, the air will freeze directly and block the pipeline.
The density of hydrogen is extremely low and its molecules are extremely small. Hydrogen can penetrate places where other gases cannot penetrate because of their small molecules. Therefore, hydrogen pipeline valves place extremely high requirements on design and manufacturing.
At the same time, the hydrogen tank is large, but also very light, which is not very friendly to the overall design.
In addition, hydrogen will penetrate into metal parts, causing hydrogen embrittlement problems.
As for the dinitrogen tetroxide/hydrazine engine, this is similar to a solid fuel rocket. Not only is the fuel expensive, but damn, it is poisonous! It is called poison.
The most promising one at present is the liquid oxygen methane engine.
Although the specific impulse of liquid oxygen methane is lower than that of the excellent hydrogen-oxygen combination, it is still higher than that of liquid oxygen kerosene, making this fuel-oxidizer combination of practical value.
The design and manufacturing difficulty of methane fuel tanks is relatively low. Compared with the combination of hydrogen and oxygen, the boiling point of methane is much higher than that of liquid hydrogen, close to that of liquid oxygen, and the molecules are large.
Therefore, the fuel tank of the liquid oxygen methane rocket is about the same size as the oxygen tank, which saves a lot of trouble.
Most of the design cost and most of the manufacturing cost of a rocket engine is its turbopump.
Because the density of hydrogen is too low, the hydrogen pump rotation speed is required to be high, and the design is very difficult. A multi-stage pump is required to achieve the desired combustion chamber pressure.
Methane rockets have greatly reduced the difficulty from fuel tanks to pipelines to turbo pumps. Even one stage of the turbo pump is enough.
Compared with kerosene rockets, the liquid oxygen and methane combination engine is less prone to coking.
It not only increases the temperature of the gas generator, but also increases the pressure potential of the main combustion chamber. It also saves cleaning work when used again.
Therefore, space agencies or companies in various countries are currently developing liquid oxygen and methane engines. Blue Origin is working on liquid oxygen and methane engines, and Elon Musk’s SpaceX next-generation heavy rocket also uses a liquid oxygen and methane combination.
Of course, hydrogen-oxygen engines are also very competitive.
Also, let’s talk about Saturn V.
Although it has the most powerful motivation in history, its principles are not the most advanced.
The combustion chamber pressure of the Saturn V F1 engine is less than 10 MPa (i.e. 100 standard atmospheres), which is detrimental to improving performance. The engine chamber pressure of the gas generator cycle is generally low, and the current engine chamber pressure of SpaceX is less than 10 MPa.
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High chamber pressure requires the adoption of more advanced principles, such as the staged combustion cycle engines used by Mao Xiong and Dong Tang. The ultimate chamber pressure has reached 25 MPa (25o atmospheres).
At that time, due to insufficient thorough research on the principles of kerosene rocket engines, it was believed that the chamber pressure of the kerosene rocket engine could not be increased, so NASA abandoned the kerosene staged combustion cycle engine.
The real reason is that there is a problem with the crude oil they use, and the kerosene produced has too high a sulfur content, which causes damage to the engine under high chamber pressure.
Since the crude oil produced in the oil field has low sulfur content, Mao Xiong easily realized the high chamber pressure kerosene engine. We can go back and study the principle without any delay.
Therefore, luck plays a big role in scientific research. The plankton in the ocean hundreds of millions of years ago determined the future development direction of rocket science.
Later, in the 1970s, NASA fully shifted to recyclable spacecraft and reusable rocket engines. In principle, hydrogen-oxygen engines are the most suitable for reuse.
Hence the staged combustion cycle hydrogen-oxygen engine later represented by the space shuttle SSME engine.
Mao Xiong has also embarked on this path in order to develop reusable spacecraft. The Rdo12o of the Energy rocket is a high-thrust hydrogen-oxygen engine of the same stage as SSME.
As for why, NASA now does not use its own oxyhydrogen motive force, but uses the motive force of the furry bear.
The main reason is that there is a problem with their technical route. In fact, strictly speaking, it cannot be said to be a problem.
But when they switched from kerosene-liquid oxygen engine to hydrogen-oxygen engine, the curve was too sharp, and now it is impossible to move up or down.
It is commonly said that if you take too big a step, you will break your balls.
For Galaxy Technology, due to the possession of submetallic hydrogen, storage and processing have become very simple.
If the subsequent research on metallic oxygen goes smoothly, it will be even more powerful for the hydrogen-oxygen motive force.
The problem facing the hydrogen-oxygen engine research institute is mainly the problem of the turbocharger pump.
Only by solving this problem can the recyclable hydrogen-oxygen engine be almost completed.