kjernereaktor

A kjernereaktor, often called a nuclear reactor, is a device used to initiate and control a sustained nuclear chain reaction. This process typically involves the fission of heavy atomic nuclei, such as uranium or plutonium. When a neutron strikes a fissile atom, it can cause the nucleus to split, releasing a significant amount of energy in the form of heat, along with more neutrons. These secondary neutrons can then go on to cause further fissions, leading to a chain reaction.

Control rods, made of neutron-absorbing materials like cadmium or boron, are used to regulate the rate of fission. By inserting or withdrawing these rods, operators can manage the number of neutrons available for fission, thus controlling the reactor's power output. The heat generated by fission is typically used to produce steam, which then drives turbines connected to generators to produce electricity.

Nuclear reactors are employed in various applications, most notably in power plants for electricity generation. They also play a role in research, the production of medical isotopes, and for propulsion in submarines and aircraft carriers. Safety systems are paramount in reactor design, including containment structures and emergency cooling systems, to prevent the uncontrolled release of radioactive materials. The management of spent nuclear fuel and radioactive waste is a significant challenge associated with nuclear power.