Before returning to the college entrance examination, I became popular in the science circle

In order to achieve magnetic confinement, a device that can generate a sufficiently strong toroidal magnetic field is needed. This device is called a "Tokamak device" - TOKAMAK, which is composed of "ring", "vacuum" and "magnetic field" in Russian. ", "coil" abbreviation composed of prefixes.

"Yes, as early as 1954, the big brother Kurchatov Atomic Energy Institute next door built the world's first tokamak device!" Wu Tong nodded. Tokamak is indeed the world's mainstream research.

When studying controllable nuclear fusion, Wu Tong will naturally not miss the progress and information along the way in the research and development of controllable nuclear fusion.

The country started research in the 50s, and it seems to be going well, right?In fact, if it is to be put into practical use, the energy of the input device must be much smaller than the energy of the output, which is called the energy gain factor - Q value.

The tokamak device at that time was a very unstable thing. After more than ten years of operation, it did not achieve energy output. It was not until 1970 that the former Soviet Union obtained actual energy output for the first time on the tokamak device that had been improved many times. The energy output, however, could only be measured using the most advanced equipment at the time. The Q value was approximately one part per billion.

Don’t underestimate this one-billionth. This gave the whole world hope. So the whole world worked hard under this encouragement and built their own large-scale tokamak devices. Europe built the Joint Environmental Tokamak-JET. , the Soviet Union built the T20...
Then gradually, records were set again and again. In 1991, the European Joint Ring achieved the first deuterium-tritium operation experiment in the history of nuclear fusion. Using a 6:1 deuterium-tritium mixed fuel, the controlled nuclear fusion reaction lasted for 2 In seconds, an output power of 0.17 million kilowatts was obtained, with a Q value of 0.12.

1993年，海对面在TFTR上使用氘、氚1：1的燃料，两次实验释放的聚变能分别为0.3万千瓦和0.56万千瓦，Q值达到了0.28。

When Hong Kong City celebrated its return to China in 97, United Europe set a world record of 1.29 kilowatts, with a Q value of 0.60, which lasted for 2 seconds.

Only 39 days later, the output power increased to 1.61 kilowatts, and the Q value reached 0.65.

Three months later, the deuterium-deuterium reaction experiment was successfully carried out on Japan's JT-60. Converted to a deuterium-tritium reaction, the Q value could reach 1.Later, the Q value exceeded 1.25.

Although the latter reaction is not practical, it is also a masterpiece of Tokamak theory that can really produce energy.

Naturally, China has not slowed down its pace of progress. As early as the 70s, several experimental tokamak devices were built in China—Hyre 1 (HL-6) and CT-6. Later, HT-6 and HT-1B were built. , as well as the reconstruction of HL2M and the construction of Gyre [-]...

The core of the tokamak device is the magnetic field. To generate a magnetic field, a coil must be used and electricity must be applied. Where there is a coil, there is a wire, and where there is a wire, there is a resistance.

The closer the tokamak device is to practical use, the stronger the magnetic field will be, and the greater the current will be passed through the wire. At this time, the resistance in the wire will appear. The resistance will reduce the efficiency of the coil and limit the flow of large currents, which cannot Generate sufficient magnetic field.

The tokamak seems to be coming to an end.

Fortunately, the development of superconducting technology has made Tokamak a turnaround. As long as the coil is made into a superconductor, the problem of large current and loss can be solved in theory. Therefore, the Tokamak device using superconducting coil was born. This is super Tokamak. "So far, there are four countries in the world that have their own large-scale super tokamak devices, France's Tore-Supra, the T-4 from the bear next door, Japan's JT-15U, and our EAST, which is the Plasma Research Institute of the University of Science and Technology of China. The so-called Eastern Ring!"

After studying the information on this section, Lu Xiao knew this section quite well.

“Domestically, if I remember correctly, in July, there was a breakthrough that was close to the world level. At the Institute of Plasma Physics, Chinese Academy of Sciences, the 2012 Eastern Superring (EAST) superconducting tokamak physical experiment was successfully completed.

There, low clutter and ion gyration radio frequency waves were used to achieve multiple modes of high-confinement plasma and long-pulse high-confinement discharge, creating two world records for tokamak operations: obtaining 400 million-degree high parameters for more than 2000 seconds. Diverter Plasma; obtain highly constrained plasma discharges that are stable and repeatable for over 30 seconds! "

Even when Lu Xiao was working on the Canglong J-35 project, he was not blind to major trends in the scientific research circle.

"Yes, these are the longest high-temperature divertor plasma discharge and the longest high-confinement plasma discharge in the world, marking that we are at the forefront of the world in research on steady-state high-confinement plasma!" Wu Tong Naturally, the news of this progress and breakthrough was not missed. China actually has a considerable accumulation foundation in tokamak.

"However, Brother Lu, although tokamak is the mainstream of controllable nuclear fusion research, it is not the only research method!" Since he is a confirmed collaborator, from the initial collision of ideas, he knew that Lu Xiao was in this section, and the same With a lot of research, Wu Tong said bluntly: "However, this does not mean that this direction is definitely correct!"

Lu Xiao did not think that Wu Tong was arrogant for denying the mainstream international methods. Scientific research should be about breaking conventions and daring to think that others dare not think. Only then can breakthroughs be made from angles that ordinary people cannot consider.

"Before the breakthrough of controllable nuclear fusion technology is born, no possibility should be ignored. This is only the mainstream of world research at present, not the correct mainstream. Wu Tong, do you want to go in the direction of stellarator?"

Stellar simulator, as the name suggests, imitates stars. Its essence is a nuclear fusion reaction research equipment.

Fusion reactors operate on two types of hydrogen atoms, deuterium and tritium, and inject these gases into a confinement chamber.

Then, energy is applied to them, causing the electrons of these hydrogen isotope atoms to break away from the atoms and form a plasma. This process releases huge amounts of energy.These plasmas are prevented from approaching the walls by strong magnetic fields, created using superconducting coils that surround the confinement chamber and the currents present in these plasmas.

The advanced concept of stellarators actually has a lot to do with Princeton University.Although Germany is currently the main research and leader in this technology, this concept was first proposed by Professor Lyman Spitzer, a physicist at Princeton University.

This is because the design was too complex at the time, and there were insurmountable obstacles from both a materials and engineering perspective. This genius idea was shelved until recent years. With the advancement of materials and other technologies, it was mentioned again.