Water is the slowing down of neutrons produced in nuclear reactors of the best materials. LWR (light water reactor / lwr) is a mixture of water and soft drinks as a coolant and moderator of the reactor, is a way of peaceful use of nuclear energy. Light-water reactor on a nuclear fission reactor containing heat can be divided into two kinds of pressurized water reactors and boiling water reactor, nuclear power plant is currently used by most international of the two reactor types. According to statistics, in 1992, 413 nuclear power plants in operation, the light-water reactor nuclear power plant accounts for about 64.15%, 80% of installed capacity, with orders already under construction and will account for 80% of the light water reactor nuclear power plant, installed capacity will account for 90 %.
Translated by Google
Action principle
With light water as moderator and coolant of nuclear reactors are called light-water reactors, pressurized water reactors, including boiling water reactors and processing. Light water is ordinary water, widely used in the reactor moderator and coolant. Compared with the heavy water, light water with low-cost advantages, in addition to the reduction efficiency is also high. Boiling water reactor is characterized by water vapor without going through the heat exchanger directly to the gas turbine, thus preventing the low thermal efficiency; plus of PWR is suppressed with high-pressure boiling light water is generally added to the 100-160 standard atmosphere (atm ), so the heat exchanger to a cooling system (remove the heat generated by the core) and secondary cooling (taken place of the steam turbine) is completely isolated.
Translated by Google
Pressurized water reactor
pressurized water reactor One-loop cooling water at high pressure (15 × 10 ^ 6 ~ 16 × 10 ^ 6pa) run through the cycle of the reactor vessel, a loop temperature of 320 ℃ or so, remains liquid without boiling reactor. Pressurized water reactors to low enriched uranium dioxide as fuel, light water purification for pure nuclear coolant and moderator. A coolant loop to the core issue of heat transfer through the steam generator to heat water to the secondary circuit, and produce steam to drive turbine to generate electricity. PWR fuel enriched to 3% in order for the zirconium alloy cladding, each more than 200 fuel elements assembled into a square root cross-section of fuel assembly, installed in the core.
Translated by Google
Boiling water reactor
boiling water reactor
Translated by Google
Heavy water reactor
Heavy water is deuterium oxide (d2o) as a moderator of the reactor is known as heavy water reactor, or referred to as heavy water reactor. Now almost all reactors use thermal neutrons, so the reactor moderator is an integral part of the moderator and the neutron-neutron collisions to reduce the number of neutrons which then loses its meaning. Therefore, it is very excellent heavy water moderator, it is tied with the most commonly used graphite moderator.