RBMK

RBMK (Russian: Реактор Большой Мощности Канальный, Reaktor Bolshoy Moshchnosti Kanalnyy, "High Power Channel-type Reactor") is a class of nuclear reactor designed and built by the Soviet Union. The RBMK is a type of thermal-neutron reactor that uses graphite as a neutron moderator and normal water for cooling.

Design and operation

The RBMK design is unique in its use of graphite as a neutron moderator and water as a coolant. This combination allows the reactor to have a positive void coefficient, meaning that the reactor's power output increases as the water coolant boils into steam. This characteristic, while advantageous in certain operational scenarios, can also lead to instability and potential safety issues.

The RBMK reactors are housed in large reactor buildings and are characterized by their large size and relatively low construction costs. The reactor core is made up of a large number of individual fuel channels, each of which can be independently refueled while the reactor is still operating, a feature known as on-load refueling.

Safety and incidents

The RBMK design has been criticized for its inherent safety flaws. The most notable incident involving an RBMK reactor was the Chernobyl disaster in 1986, which resulted in a catastrophic nuclear meltdown and significant release of radioactive materials.

Following the Chernobyl disaster, significant modifications were made to existing RBMK reactors to improve their safety. These included changes to the control rod design, improvements to the emergency cooling systems, and the addition of a containment building around the reactor.

Legacy

Despite the safety concerns and the Chernobyl disaster, RBMK reactors continue to be used in Russia today. They are, however, being phased out in favor of more modern and safer reactor designs.

See also

• Nuclear power in Russia
• List of nuclear reactors
• Chernobyl disaster