Pressurized heavy-water reactor facts for kids

Schematic diagram of a pressurised heavy-water reactor

A pressurized heavy-water reactor (PHWR) is a nuclear reactor developed by Canada. It commonly uses uranium as its fuel. It uses heavy water (deuterium oxide D₂O) as its coolant and neutron moderator. The heavy water coolant is kept under pressure. This allows it to be heated to higher temperatures without boiling. While heavy water is a lot more expensive than ordinary water, it creates greatly enhanced neutron economy. This allows the reactor to operate without fuel-enrichment facilities (offsetting the additional expense of the heavy water).

Related pages

• Pressurized water reactor

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  ²³⁵U fission cross section - while a nonlinear relationship is apparent, it is clear that in most cases lower neutron temperature will increase the likelihood of fission, thus explaining the need for a neutron moderator and the desirability of keeping its temperature as low as feasible.

See also

In Spanish: Reactor de agua pesada a presión para niños