Corium (nuclear reactor) Corium (nuclear reactor) Corium (also called fuel containing material (FCM) or lava-like fuel containing material (LFCM)) is the lava-like mixture of fissile material created in a nuclear reactor's core during a nuclear meltdown. It consists of nuclear fuel, fission products, control rods, structural materials from the affected parts of the reactor, products of their chemical reaction with air, water and steam, and, in the event that the reactor vessel is breached, molten concrete from the floor of the reactor room. The heat causing the melting of a reactor may originate from the nuclear chain reaction, but more commonly decay heat
Nuclear reactor heat removal total heat produced in the nuclear reactor is: formula_5 where formula_6 is the mean neutronic flux and V is the fuel volume (normally measured in formula_7). Recovery of this amount of heat is achieved by using cooling fluids whose temperature at the entrance to the reactor channel formula_8 will increase with the distance traveled in the channel. The thermal balance of the channel is expressed by the relationship: formula_9 where formula_10 is the flow rate of the cooling agent, formula_11 is the specific heat at constant pressure, formula_12 is the increase in the temperature of the fluid after passing a