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What`s Fusion

The Sun, Gigantic Fusion Power Plant

The Sun's secret of blazing for 10 billion years

The source of life energy for human beings: gigantic fusion power plant

The conditions for solar power station

The source of life energy for human beings: gigantic fusion power plant

  • It should be plasmatic. (The fourth state of matter)
    - The state that a nucleus and an electron are freely moving around after being separated from each other at the temperature of 150 million degrees Celsius.
  • It requires the fusion reaction
    - Four freely moving protons of hydrogen join together at the state of the plasma to form a helium nucleus.
The nuclear fusion keeps the Sun ablaze

The mass reduced by forming of a helium nucleus through the nuclear fusion is converted into the enormous solar energy and sets the Sun ablaze

※ The radiating stars like the Sun generate the energy through the nuclear fusion. The nuclear fusion is the process by which multiple light atomic particles join together to form a heavier nucleus at ultra high temperature of *plasmatic state. The reduced mass in this process is converted into the huge quantity of energy and it is called the 'Fusion energy'.

The nuclear fusion keeps the Sun ablaze.
What is Plasma?It is not solid, liquid or gas but the fourth state of the matter that is an ionized gas of which a nucleus and an electron are separated. 99% of the universe is composed of plasma. A lightening and an aurora, or everyday gadget like a fluorescent lamp and a neon sign are all made up of plasma. Lightening, Aurora, Neon sign

The Global Human Project of Making the Solar Energy

The Dream by Albert Einstein
The Dream by Albert Einstein
  • German-born American Physicist
  • Best-known for his Special Theory of Relativity(1905)
  • The realistic possibility of nuclear fusion reaction on Earth
  • was predicted through his famous mass-energy equivalence, E = mc2
To Make the Solar Energy
The plasma at 100 million degrees Celsius is a requirement (Environment).

In order to generate the plasma the same as the one at the core of the sun, it should be heated up to the temperature of 100 million degrees Celsius.

Why does nuclear fusion require the temperature of 100 million degrees Celsius? The nuclear that repel each other lose their repelling power at higher temperature than 100 million degrees Celsius and then generate nuclear fusion.

The vessel to hold the plasma at 100 million degrees Celsius is a requirement. (Device)

There exists no vessel to hold reliably the heated plasma on Earth. Therefore, by creating a toroidal magnetic field, we can confine the plasma. It means that we confine plasma by making a vessel generating a toroidal magnetic field.

The sea water is a requirement (Fuel).

The simplest mixture generating the nuclear fusion is the fusion of 'deuterium' and 'tritium'. These two fuels to generate nuclear fusion can be obtained from the unlimited source of the sea water.

Fusion Energy Converting into Electricity

※ TOKAMAK, the most advanced nuclear fusion reactor, is a machine producing a toroidal magnetic field for confining a plasma to generate a nuclear fusion. It can generate a large amount of electricity by heating the steam and operating turbines after being converted into thermal energy.

Several Callenges to Meet
Make a 'toroidal magnetic field line basket' to confine plasma thoroughly.

It is not easy to make a 'toroidal magnetic field line basket' which can confine plasma fully. Since the 1940s, three devices have been created such as Magnetic Mirror, Torus-shaped Device, Stellarator. But they all came to a deadlock due to the nature of plasma and the technological limits.

Fusion Energy Converting into Electricity
Magnetic Mirror

When two mirrors are placed at either and of a solenoid to increase the internal volume of the reaction area, magnetic field lines appear as in the figure. The mirror effect results in a tendency for charged particles to bounce back from the high field region. Therefore, the plasma can be confined between coils. However, some particles of plasma escape from the ends. (An electric currents, Coils, Plasma, Reflected particles, Reflected particles, Magnetic field lines)

Torus-shaped Device
Torus-shaped Device
  • Loose coils
  • Dence coil
  • An electric current
  • Particles wound by magnetic field lines
  • Cail
  • magnetic field lines
  • Escapin course of particles affected by the electric field from the magnetic field line
  • A section of the magnetic field line
  • lons gathering at the top
  • The red shading signifies the field intensity(The right side is stronger)
  • The course of electric field caused by irregular distribution of ions and electrons
  • Electrons gathering at the bottom
Torus-shaped Device Particles can't be confined even within the torus-shaped magnetic field lines.

The purple lines in the figure above are magnetic field lines made of coils. In this torus-shaped coil distribution, the coils on the inside get clustered together so that the centre gains a stronger magnetic field. Then, the distribution of ions and electrons becomes uneven due to the dap between the electropositive and electronegative of particles, and an electric field tending towards the bottom arises, This electric field exerts a bad influence on plasma particies and the plasma escapes from the torus-shaped magnetic field lines.

plasma
stellarator Using a toroid bent into a figure-eight shape solvel issues faced by torus-shaped magnetic field lines but...

The stellarator in the figure above was a figure-eight shape invented by Dr. Lyman Spitzer, wrapped by the coils which create magnetic fields. Plasma particles on the inner portion of the tuve are subjected to a greater magnetic force than those at the outside. By bending a toroid, it was possible to solve the issue of irregular distribution of a nucleus and an electron in a torus-shaped magnetic field line. It was feasible in theory but impracticable to achieve the expected results as the technologies then were lack of the high precision to manufature the device.

In 1968, Soviet scientists finished a successful test of a T-3(Tokamak), a machine for confining plasma by producing a toroidal magnetic field by external coils with a negligible current flowing through the plasma. Thus, the tokamak continues to be the most promising device for stabilizing plasma.

(Plasma current, Magnetic field lines generated by plasma current) + (Electric current flowing in toroidal coil, Magnetic field lines generated by flowing toroidal coil current) = (Magentic field line basket inside the tokamak(Magnetic field lines, Plasma)

Tokamak magnetic field and current

Tokamak device confining plasma easily and stably
Tokamak device confining plasma easily and stably
  • Bent magnetic field lines
  • Electric current
  • Coils to generate the toroidal megnetic field
  • Poloidal coil
  • Vessel
  • Coils inducing plasma current

Tokamak device confining plasma easily and stably

Isolate plasma from the impurities.

When the plasma mixed with impurities from air molecules or walls of a vessel is heated, the temperature doesn't rise and then it emits the thermal energy as a form of a light. To solve the problem, there has been much effort made to study exhaustion technologies and develop materials that won't be affected by the impurities in a high-degree vacuum condition.

Solve the problem of plasma imperfection
Solve the problem of plasma imperfection
  • Stablity
    • Force of returning to the bottom at a slight rocking
    • The property to recover to the original condition in spite of the rock-ingthe rocking.
  • Instability
    • Even a slight movement causess the slide
    • It aggravates rocking.

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