Essay on “Future Source of Nuclear Fusion” Complete Essay for Class 9, Class 10, Class 12 and Graduation and other classes.

Future Source of Nuclear Fusion

Nuclear fusion reaction takes place, when the nuclei, which are positively charged, have enough kinetic energy to overcome their electrostatic force of repulsion. The nuclear fusion takes place either when one nucleus is accelerated to high energies by an accelerating device, or when the energies of both nuclei are raised by the application of very  high temperature. The sun is an example of thermonuclear fusion in nature. Thermonuclear fusion is the basic principal in the formation of the hydrogen bomb. Thermonuclear reactions occur when a proton is accelerated and  collides with another proton. These two protons then fuse and result in a deuterium nucleus, which has a proton, neutrino and abundant energy. Such a reaction is not self-sustaining because the energy so released in the procedure is not readily imparted to other nuclei. Thermonuclear fusion of deuterium and tritium will generate a helium nucleus and a high- energy neutron, which  can help sustain further fusion.

Thermonuclear reactions depend on high energies. In 1989 two electrochemists shocked the scientific world by claiming to achieve a room- temperature fusion in a simple laboratory. They had little proof to back up their discovery, and were not credited with their so- called accomplishment. The two scientists were Stanley Pons of the university of Utah and Martin Flesichmann of the University of Southampton in England. Fusion reactions that occur within a plasma serve to heat it further, because the portion of the reaction product is transferred to the bulk of the plasma charged helium nucleus carries 3.5 MeV. The neutron escaped the plasma with little interaction and , in a reaction , could deposit its 14.1 MeV in a surrounding lithium blanket. The neutrons activity would breed tritium and also heat as an exchange medium which could be used to produce steam to turn generator turbines. However, the plasma  also loses thermal energy though a variety of processes: conduction, convection, and electromagnetic radiation. Ignition occurs when the energy deposited within the plasma by fusion reactions equals or exceeds the energy being lost. In order to achieve ignition, plasma must be combined and heated.   

Since 1950 , in research work magnetic fields have been used to contain the charged particles that constitute plasma. The density required in magnetic- confinement fusion is much lower than atmospheric density, so the plasma vessel is evacuated. Magnetic- field configurations fall into two typed: open and closed. In an open configuration, the charged particles, which are spiraling along magnetic field lines maintained by a solenoid, are reflected at each end of a cell by stronger magnetic fields. Present day mirror machines retard this loss by suing additional cells to set up electrostatic potential that help confine  the hot ions within the central solenoidal field. In a closed reaction, the magnetic- field lines along which charged  partials  move are continuous within the plasma. This closure has most commonly taken the form of a torus, or doughnut shape, and the most commonly taken the form of a torus, or doughnut shape, and the most common example is the tokamak. In a tokamak the primary confining filed is toroidal and is produced by coils of surrounding the vacuum vessel. This toroidally – flowing current wraps itself around the plasma. The poloidal magnetic field, at right angles, that stronger torodial field, acting together ,yield magnetic field lines that spiral around the torus. This spiraling ensures that a particle spends equal amounts of time above and below the toroidal midplane, thus cancelling the effects of a vertical drift that occurs because the magnetic field is stronger on the inside of the torus than on the outside. Additionally, a certain type of plasma called Tokamak Plasma can be heated to temperatures of 10-15 million K by the current flowing in the plasma. At higher temperature the plasma resistance becomes too low for this method to be effective , and heating is accomplished by injecting beams of very energetic neural particles into the plasma. These ionize, through collisions, alternatively, radio frequency waves are various periodic particle motions. The waves give energy to these resonant particles, which then transfer it to the rest of the plasma through collisions. Another methods, which is followed  since about 1974 , is termed inertial confinement. The temperature required to ignite a fashion reactor is in the range of 100-250 million K, several times the temperature of the centre of the sun. the goal of fusion is in effect, to produce and hold a small star. It is a scary and mind- numbing research, which is considered to be the most advanced in the world.

Once we are able to make it possible to use it in an effective way in common life, the days will not be far when we fulfil our wish to reach for the stars.