Nuclar Reactors

A nuclear reactor is device used to initiate and control a sustained nuclear chain reaction. It produces and control the release of energy from the splitting other atoms as a result of fission within the reactor.  

There are different design for nuclear reactors but the main factor is to consider the component, the arrangement and controls,  the basic component of a nuclear reactor are the shield, fuels, moderator, reflector and the coolant.

If the supply  of neutrons can be maintained constant in an assembly of fissionable materials a self-sustained chain reaction can occur. Chain reaction is possible because more than one neutron is produced any time a neutron is used off in the cause of the reaction. Any time a fuel (a uranium-235 for example) split, 2-3 neutrons is release with about 190mev  of energy, this energy is removed by a circulating fluid called coolant,

A moderator is also a component of the reactor, it is made of light element like hydrogen or carbon intermixed with the fuel, their main function is to reduce the energy of the neutron , a reflector function is to bounce back any escaping fission neutron thereby reducing neutron loss.

The reaction is said to be self-sustaining if fission neutron are produced from previous fission ,when a reaction depend on a separate supply of neutrons it is said to be sub-critical while in super-critical neutron will accumulates.

 A shield function to protect personnel against poisonous emission and radiations from the reactor.

Nuclear reactors can be classified as  based on their fastness as fast, intermediate and thermal, based on fuel used  those with highly enriched uranium uranium-235(90%), slightly enriched uranium(1-2%) and natural uranium(0.7%), plutonium reactor and uranium-233.

 Reactors can also be classified based on the method of heat removal. E.g, coolant only, fuel mixed with coolant, moderator coolant & fuel, moderator and coolant.

Based on the purpose of the reactors we can have research , prototype, propulsion, heat source, electric power generation and for isotope generation,

In generation of electricity, there is always a mechanical part and the electrical part, the mechanical part here is the nuclear reactor which is responsible for the generation of the necessary mechanical work to drive the alternator .

The energy generated inform of heat can be used in working fluid to turn a turbine or propeller in generation of electricity and propelling of ship respectively. The working fluid is either water or gas, the heat from this will boil the water into overheat steam which will be used to driving the turbine.