Unformatted text preview: 1- Pressurized Water Reactor System PicturePressurized water reactors consist of a single fuel element assembly of up to 200 zircaloy cadded fuel 'pins'. These 'pins' are immersed in a large steel pressure vessel containing ordinary 'light' water. The light water serves as both a coolant and moderator. Light water has a higher neutron-absorbing capacity than heavy water (D2O). This causes it to increase the percentage of 235U in the core. Uranium dioxide is a source of fuel for this reactor. The pressure vessel consists of control rods that pass through the lid, the light water under pressure, and the reactor core. The water attains a temperature of approximately 270 C without boiling, due to a pressure of about 13.8 to 17.2 MPa. This pressure is maintained through a pressurizer. The 'light' water passes in a closed circuit to a heat exchanger. This causes the water in the heat exchanger to heat up and convert to steam. This steam drives one or more turbine generators, is condensed, and pumped back steam....
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- Spring '09
- Pressurized water reactor, Nuclear fuel, Neutron moderator, 18 months, Boiling water reactor, Water Reactor