Ydinrunko

Ydinrunko is a Finnish term that translates to "nuclear core" or "reactor core." It refers to the central part of a nuclear reactor where the nuclear fission reaction takes place. This is where the fuel, typically enriched uranium or plutonium, is housed within fuel assemblies.

The primary function of the ydinrunko is to sustain a controlled nuclear chain reaction. Neutrons are released when the nuclei of fissile atoms split, and these neutrons then go on to cause further fission events. Control rods, made of neutron-absorbing materials like cadmium or boron, are used to regulate the rate of this reaction by absorbing excess neutrons.

The heat generated by the fission process within the ydinrunko is transferred to a coolant, such as water, gas, or liquid metal. This heated coolant is then used to produce steam, which drives turbines to generate electricity. The design and composition of the ydinrunko are critical for the safe and efficient operation of a nuclear power plant. Materials used in its construction must withstand high temperatures and intense radiation.