"Rupert, didn't you say that the miniaturization of nuclear fusion reactors is not a big problem, why hasn't there been a good news for me for more than two months?"

Walking into the nuclear fusion laboratory, Lu Yi looked at Rupert, who seemed to have less hair, and shouted: "If there were no objective factors, I should consider adding funds to you." ”

"Lu, this time I really want you to increase the funds."

Rupert looked up from a piece of data and said, "Materials don't work, superconducting materials don't." ”

"What!"

Hearing that the material was not good, Lu Yi's expression instantly became serious, and he asked, "Superconducting graphene material is not good?" ”

"Unfortunately, no."

Rupert shook his head and said: "With the mature nuclear fusion reactor program as the foundation, I have solved the problem caused by the equal proportion reduction of the first inner wall with the young men in the laboratory for more than two months, solved the problem caused by the equal proportion reduction of the lithium metal cladding, and improved the deflector to be smaller on the original basis."

But in the end, there is an unsolvable problem in confined magnetic fields, a problem caused by the properties of the material. ”

"The shrinking of the outer field coil makes the confined magnetic field strength unable to confine the fusion inside the plasma?"

Lu Yi guessed what the problem Rupert was talking about, rubbed his eyebrows and said, "What is the current minimum reactor mass?" And how much power can it reach? ”

"It's more than 12 times smaller than the big guy outside."

Rupert took a copy of the parameter data to Lu Yi and said: "The minimum can reach 87.6 tons, but it is still far from your psychological bottom line of 20 tons."

Because of the shrinking of the first inner wall and lithium breeding cladding, it cannot carry too powerful fusion, and its power is only 160M compared to the 32,000M power outside. ”

"87.6 tons, it's still too big." Lu Yi smiled bitterly and threw aside the parameter data in his hand and shook his head.

"Lu, if you compare it with a launch vehicle in terms of energy power, 87.6 tons is actually a very small number.

DT fusion contains 30 percent of the energy in the simple exhaust gas, 30 percent of the thermal energy of 160M, and the thrust generated by Wei Hong's thermal expansion engine will be more than 100 times that of Saturn 5.

To know how big Saturn 5 is, 3000 tons! This 100-fold thrust is enough to force a spacecraft with a mass of more than 100,000 tons into the sky. ”

Rupert persuaded Lu Yi that this is really the limit of the miniaturization of nuclear fusion reactors, and this energy power combined with a thermal expansion engine is enough to send the spacecraft into the sky and achieve practical applications.

"I'm sorry, Rupert you should go get some sleep before you can continue your dreams.

Our material can't withstand the energy impact of 100 times the Saturn 5 thrust you mentioned, and according to the properties of the superconducting graphene coil, the magnetic field blocking limit can withstand up to 28,000 kN thrust.

This thrust is not as strong as the Saturn 5, and if it exceeds this thrust limit, the plasma impact will directly cause the magnetic field to shatter. ”

Lu Yi said regretfully: "The most important thing is that a reactor costs 87.6 tons, and then counting the propulsion fluid and other messy but necessary equipment and instruments, then this spacecraft is conservatively 800 tons, and the construction period will take more than 5 years, I can't afford to wait." ”

A spacecraft does not mean that a space engine can go into space, as a reactor as the core of energy, its mass determines the volume of supporting equipment of other spacecraft.

This is the same reason that even if the ignition of a high-displacement engine does not start, the oil consumption of a hot engine is higher than that of a general-displacement engine.

"I really don't know why you're in such a hurry, do you really want to go to Jupiter while you're young and flutter in the wind?"

Rupert said helplessly: "But I can't help it now, this is the technical barrier brought by materials, and it is not something that I, a person who studies controlled nuclear fusion, can solve, you can only find material experts for this problem." ”

"Is there only the limit of the external magnetic field coil now?"

Lu Yi was silent and said, "If we ignore this question, how much can we shrink the reactor to?" ”

"If I ignore the problem of the external magnetic field coil, I can reduce it to less than 10 tons, about 9.43 tons, and it can be as small as it is."

Rupert shrugged and said, "But that's not possible, unless you have ambient superconducting materials." ”

"9.43 tons." Lu Yi exhaled deeply, took out his mobile phone and called Hu Feng who was outside.

A few minutes later, Hu Feng came in from outside, and immediately showed a wry smile after hearing Lu Yi's request.

"Boss, if you need high-temperature or radiation-resistant materials, the laboratory has made a little breakthrough in this in the past two months, and I can come up with better performance, but there is no way to do superconducting materials in a short time."

No more than high-temperature or radiation-resistant materials, the breakthrough of superconducting materials bets on more quality than technical components, just like the magical 1.05° angle of graphene superconductivity, which is purely discovered by luck, rather than accurate derivation of technical data.

"There really can't be helped?" Lu Yi was a little disappointed, but if he waited, it would be too long.

Every new spaceship is custom-made, maybe the second one can be done in two years according to the current industrial strength, but the first one is impossible to complete in five years.

"It's not like there's no way."

Hu Feng hesitated and said: "This method may not be a solution for others, but for the boss, you can actually consider it." ”

"Tell me, if it doesn't work, I don't think the production capacity of superconducting graphene materials is enough, and it is necessary for you to provide more molds together."

Lu Yi raised his eyebrows, the materials laboratory has not set project goals for them recently, and it is necessary to stimulate their research enthusiasm.

"Metallic hydrogen!"

Hu Feng had a toothache when he heard the superconducting graphene material, the last time because of this material, more than 40,000 scientific research dogs in the country piled up atomic building blocks for two months, and now the material researchers in the whole country have a psychological shadow when they hear the superconducting material.

"Metallic hydrogen has good superconducting properties and is a superconducting material at room temperature.

At present, there are two relatively mature metal hydrogen preparation methods in the world, one is the dynamic compression method, which is obtained by using strong magnetic field impact compression, and the other is obtained by compressing liquid hydrogen by using a press or hydraulic press of more than 1,000 tons.

Of course, the cost of preparation is a little expensive, but I don't think that's a problem for you, boss. ”

"That metallic hydrogen with more than 30 times the energy of TNT explosives? Are you sure it's stable enough not to explode when you're using it? ”

Lu Yi subconsciously ignored the so-called cost problem, but turned the problem to another aspect.

In the aerospace industry and the military industry, there has been the idea of using metallic hydrogen as a solid rocket fuel, mainly to value the energy data of TNT explosives that can reach more than 30 times under the same volume.

Although it ultimately involves the issue of cost and the problem of industrial batch preparation, the aerospace industry and the military industry, which still live a tight life for many days, have abandoned this material.

"Not really, hydrogen becomes a metastable substance after being compressed into metal, which can be used with confidence."

Hu Feng nodded very confidently, in the eyes of ordinary people, it is estimated that his legs will be weak when he hears more than 30 times the energy of TNT explosives, but for a material expert like him, as long as he understands the characteristics of materials, everything is not a problem.

This is the same as the C4 is relatively stable, and the conventional open flame ignition does not explode, and the high-energy impact of the detonator must be used to ignite the characteristics, knowing this, the C4 can be pinched and played, but ordinary people don't have the courage to do so.

"If the boss is really not at ease, we can see if we can change a material, but I have only heard about this material, and the more detailed performance parameters, including the preparation technology, are not clear."

After thinking about it for a while, Hu Feng was also afraid that someone would misoperate in the future and cause the metallic hydrogen explosion and blow up Lu Yi's spaceship, so he proposed another material.

"You don't know how to say metallic nitrogen, do you?"

Lu Yi guessed what Hu Feng wanted to say, in 2018, the Chinese Academy of Sciences came up with metal nitrogen, and the specific parameters involved and the preparation technology are still being kept secret.

However, what is the difference between the energy density of TNT, which is more than ten times that of metallic nitrogen, and the energy density of more than 30 times that of metallic hydrogen? If you really want to operate it improperly, it is not the same as blowing up the spaceship, so it is better to use metallic hydrogen, at least the preparation technology is more mature.

"Calculate how much time and how much it will cost to replace this small fusion reactor with metallic hydrogen, including the supporting engine."

Lu Yi took the amount of materials used for the delicate and small reactor just given by Rupert, and the amount of superconducting materials used by Wei Hong's thermally expanding engine to block the magnetic field, and asked Hu Feng to calculate how much it would cost to replace these with metallic hydrogen.

According to his estimates, if the reactor can be reduced to less than 10 tons, then the mass of the entire spacecraft should be about 130 tons, including the mass of the propulsion working fluid and some other supporting equipment.

Such a small cargo ship weighing 100 tons without carrying people can be completed in 10 months from design to construction under the premise of money, and most of the time is still schematic design.

"In terms of time, there are not many thousand-ton presses or hydraulic presses in the world, and there are also many laboratories with dynamic compression conditions."

Hu Feng took the data given by Lu Yi, calculated it with pen and paper according to the information he had, raised his head and said hesitantly: "Boss, if you are willing to spend money, we will place orders with major industrial groups and laboratories around the world, and we can produce the required metal hydrogen in less than a month, but the cost is ......."

"How much?"

Lu Yi asked, Rupert, who has been in China for a few months and can understand Chinese, is also curious.

"2 billion, if we want to give priority to joining the queue, then counting the rush fee or breach of contract fee, it is estimated that it will cost 3 billion to 3.5 billion."

Hu Feng quoted a figure, the orders of major industrial groups are all scheduled, and the order time is generally given time redundancy to prevent accidental default.

At this time, if there is a local tyrant who wants to give priority to the queue, or whose production is urgent and needs to cut the queue to produce first, then a "rush" method will be used to use the redundant time of the original order contract, of course, the costs involved are also negotiable.

"In dollars?" Hearing the 3.5 billion Lu Yi's mouth twitched, he asked.

"Dollars."