Huang Mingzhe stayed at the Lianhuashan Nuclear Research and Development Base for more than a week, only advancing multiple controllable nuclear fusion to the sulfur atom stage.
Sulfur atoms are facing many technical problems in the future. The engineering will greatly increase the volume of the reactor. Obviously this is a problem caused by inadequate materials.
"Materials, materials! After all, it is a hurdle that cannot be overcome." Huang Mingzhe shook his head and said.
Dong Kuan patted him on the shoulder: "We have completed the theoretical design, and we will definitely be able to come up with it. It is only a matter of time."
However, Huang Mingzhe is not so blindly optimistic. From the perspective of theoretical design needs, the material performance of the reactor needs to be improved by at least about 10 times before it can barely reach the minimum standard.
If miniaturization is to be met, material performance needs to be improved by 30 to 50 times.
As a top scientist in materials science and a master of computational materials science, Huang Mingzhe knows that the current material science of the new humanity has entered a bottleneck period.
The bottleneck of atomic-molecular-level materials has arrived as expected, which is what he expected.
This is a fundamental innate limitation. Even if atomic-molecule-level materials are played with tricks, they are still atomic-molecule materials. Compared with degenerate neutron materials, quark materials have a much weaker start.
"Old Dong, I'll leave the multiple controllable nuclear fusion to you. I have to deal with the affairs of the Nuclear Fusion Engine Research Institute."
"no problem."
As for Wei Feng, he had already greased his feet. He was not very interested in nuclear fusion. It was Huang Mingzhe who pulled him here before. When he got to the carbon atom stage, he knew it was impossible.
Now he is also responsible for two large-scale physics projects, so he naturally has no time to waste here.
Huang Mingzhe came to his office, put the stand-in robot back into the storage cabin, and then left the nuclear research and development base.
In an unknown base, Huang Mingzhe exited the virtual network and exercised his body.
Coming outside the base, this is a secret base built deep in Wuyi Mountain. Now Wuyi Mountain is surrounded by natural scenic spots, and there are very few human activities.
As the core area of the new humanity, East Asia will still retain a population of 400-500 million in the future.
Although it is a human civilization area, some ecologically fragile areas still need to exit when it is time to exit.
For example, in the Qinghai-Tibet Plateau, Yunnan-Guizhou Plateau, and mountainous areas in various places, except for the historical cities that will remain, the population in other areas will be fully relocated.
Next to this base is an abandoned town.
All the residents of the town moved to the Philadelphia area in North America. It was a joke to say that it was difficult to leave their homeland. In the past, it was due to environmental restrictions. The country was overcrowded and there was no place to move.
Now the new humans occupy the entire Blue Star and resettle a lot of plain land. In addition, the concepts of the new humans are very different from those of the old humans. They do not reject migration.
Huang Mingzhe was walking in the town, and Zhang Shihe was protecting him like a shadow.
The houses in the town are still there, but plastic products and household appliances have all been recycled.
On the mottled walls, pits of lime reveal the red bricks underneath, and moss, weeds and morning glory are encroaching on human remains.
Meow……
He looked up and saw a tabby cat with cubs staring at strangers from the balcony on the second floor.
It has been less than a month since humans collectively moved here, and wild animals and plants have begun to recover.
"Life is so great. Blue Star has never cared about humans and does not need humans to save us. We are just saving ourselves." Huang Mingzhe sighed.
After walking around, I found that the traces of human beings in this town are disappearing, and the animals and plants are destroying the reinforced concrete, furniture and supplies of human existence.
Maybe in a few years, there won't be any small town here anymore.
"Let's go!"
Return to the base.
Huang Mingzhe entered the virtual network again and logged into the stand-in robot located at the Qinhuangdao Nuclear Fusion Engine Research Institute.
Qin Changge, who is responsible for the management of this research institute, was the former head of the Siweishe Laser Laboratory.
He introduced the idea of the next generation nuclear fusion engine to Huang Mingzhe.
Huang Mingzhe quickly looked through the institute's information while listening.
Generally speaking, a spacecraft engine requires two things to work - energy and working fluid.
In chemical energy rockets, the propellant is both the father and the mother, providing both the energy for propulsion and the working medium for propulsion.
This seems to simplify the structure, but according to the law of conservation of momentum, the specific impulse of the rocket is proportional to the speed of the ejected working medium, and there is an upper limit to the speed of the chemical energy rocket ejected working medium.
The nuclear fusion engine is an engine that uses the energy generated by fusion to heat the working fluid (the fusion product itself can also be used as the working fluid) to generate propulsion.
In a fusion engine, there are three types of energy coming from fusion reactions: plasma thermal energy, neutron energy, and bremsstrahlung energy.
Plasma thermal energy means that when fusion fuel undergoes fusion, the fuel atoms are ionized into useful hot plasma ions, which contains most of the fusion energy and is also easy to use energy.
Many fusion reactions or side reactions will produce fatal neutron radiation, and high-energy neutrons are also fatal to new humans.
In addition, long-term neutron irradiation can cause neutron embrittlement and neutron activation of engine components.
Neutron energy is semi-wasted in nuclear fusion direct injection engines.
Bremsstrahlung energy mainly occurs when ions and electrons collide in the hot plasma from nuclear fusion reactions.
Useful plasma heat energy is converted into useless, dangerous X-rays and cold ions, which is also considered a waste of energy.
Huang Mingzhe knows that the engineering upper limit of nuclear fusion engines is about 30% of the speed of light, but now it is difficult for humans to reach even 10%.
The main reason is that the nuclear fusion direct injection engine wastes too much energy, resulting in an extremely large fuel load ratio. It takes 50,000 tons of nuclear fuel to accelerate a 500-ton device to 12% of the speed of light, and the fuel load ratio reaches 100.
That is, 1 ton of equipment requires 100 tons of fuel to accelerate, which wastes too much energy and working fluid.
Huang Mingzhe already understood Qin Changge's thinking: "Your plan is a hybrid model, which is a good idea."
"This is also an idea that existed in the AD era. We just met the technical conditions, so we used it." Qin Changge explained with a smile.
"Let's go see your prototype."
"no problem."
…
In the laboratory, a 12-ton nuclear fusion engine is undergoing ignition testing.
This engine is somewhat different from the previous nuclear fusion direct injection engine.
The so-called hybrid mode is because the nuclear fusion engine has three modes: pure fusion, fusion afterburner engine, and dual-mode fusion engine.
The hybrid mode is a dual-mode fusion engine.
In addition to using plasma thermal energy, this nuclear fusion engine also uses neutrons and Bremsstrahlung radiation energy to heat the cold reaction mass.
In addition, dual mode can be switched to pure fusion mode, so this mode has the highest minimum thrust/propellant mass flow, and the highest exhaust velocity/specific impulse.
"Look, Chairman, this is a magnetic-inertial engine in hybrid mode." Qin Changge introduced it quickly.
"How much has fuel utilization improved so far?"
"About 26%. If working fluids are collected in outer space, the fuel utilization rate can be increased to about 85%."
Huang Mingzhe nodded. This improvement is very huge. Even if it is more conservative, it can reduce the fuel load ratio of the spacecraft by about one-third.
For a spacecraft, a small decrease in the fuel-to-load ratio can allow the spacecraft to increase its payload.