Fission reactors
A fission reactor contains a number of different parts:
- nuclear fuelsRadioactive materials, usually uranium or plutonium, used in nuclear reactors. (the uranium isotopeAtoms of an element with the same number of protons and electrons but different numbers of neutrons. that will split when triggered by an incoming neutronUncharged subatomic particle, with a mass of 1 relative to a proton. The relative charge of a neutron is 0.) - the fuel is held in rods so that the neutrons released will fly out and cause nuclear fissionThe splitting of a large nucleus to produce two smaller ones. Two or three neutrons are also released in the process. The energy from the neutrons powers a nuclear reactor. in other rods
- graphite core Slows down neutrons in a nuclear fission reactor. - graphite slows the neutrons down so that they are more likely to be absorbed into a nearby fuel rod
- control rodsIn a nuclear reactor, the control rods are used to absorb excess neutrons and control the rate of the nuclear fission reactions. - these are raised and lowered to stop neutrons from travelling between fuel rods and therefore change the speed of the chain reactionA nuclear chain reaction occurs when a neutron splits a nucleus, releasing more neutrons, which in turn go on to split even more nuclei.
- coolantA liquid used to transfer thermal energy within a system. - this is heated up by the energy released from the fission reactions and is used to boil water to drive turbineRevolving machine with blades that are turned by wind, water or steam. Turbines in a power station turn the generators. in the power station
- concrete shield - the daughter products of the fission reaction are radioactiveWhen unstable atoms give off particles that can be harmful to humans. and can be a hazardSomething that has the potential to cause harm or damage.
Many of the features of the reactor are designed to control the speed of the reaction and the temperature inside the shielding. An uncontrolled fission reaction is the basis of an atomic bombA powerful and destructive bomb that gets its power from the energy released when atoms are split..