Question

Explain the principle and working of Nuclear Reactor with the help of a labelled diagram.

Answer 1

A nuclear reactor works on the principle of achieving control chain reaction in Uranium (238) enriched with Uranium (235) generating large amounts of energy.
The reactor consists of fuel, moderators, control rods, radiation shielding and coolants.
Fuel: In reactor, fuel is fabricated in form of thin and long cylindrical rods together known as fuel assembly. The rods are surrounded by coolant for transfer of heat produced in them.
Natural uranium is used as nuclear fuels.
Moderators are used to slow down the velocity of neutrons. E.g. graphite, heavy water .
Control rods are used to control the fission rate by absorbing neutrons. Cadmium, Boron are used to serve the purpose.
Radiation shielding by the utilisation of steel, lead, concrete etc. are provided to absorb and reduce the intensity of beta and gamma radiations emitted during fission, to such low levels that it does not become harmful to operating personnel.