pool-type reactor

fission reactor

Also known as: pool reactor

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Last updated

July 1, 2026

Quick Summary

A pool-type reactor is a common design for research reactors. In this configuration, the reactor's core is submerged at the bottom of a large pool of water. This water serves multiple purposes: it acts as a coolant to remove heat from the fuel plates and as a moderator to slow down neutrons. The water also functions as a biological shield, protecting personnel from radiation.

At lower power levels, natural convection of the water is sufficient for cooling. For higher power operations, pumps are used to enhance circulation. Pool-type reactors are advantageous for research because the water allows for easy observation and the placement of "beam ports" to direct neutron beams for experiments. Some pool reactors use the surrounding water as a reflector, while others may incorporate solid moderators like graphite or beryllium around the core to reflect neutrons back into the active region.1

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nuclear reactor
Water-cooled, plate-fuel reactors
…water-cooled, plate-fuel reactor is the pool reactor, in which the reactor core is positioned near the bottom of a large, deep pool of water. This has the advantage of simplifying both observation and the placement of channels, commonly referred to as beam ports, from which beams of neutrons can be…
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…water-cooled, plate-fuel reactor is the pool reactor, in which the reactor core is positioned near the bottom of a large, deep pool of water. This has the advantage of simplifying both observation and the placement of channels, commonly referred to as beam ports, from which beams of neutrons can be…
Read More