Britannica
Sources used in this answer
How does a pressurized-water reactor transfer heat to a steam generator?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
nuclear engineering
Installation of the dome of a containment structure at the Taishan nuclear power plant, Guangdong province, southern China, 2012.
In a pressurized-water reactor (PWR), heat transfer occurs through a two-loop system designed to isolate the radioactive primary coolant from the rest of the power plant.12
- Primary Loop: Water is circulated through the reactor core, where it absorbs heat generated by nuclear fission. This water is kept under high pressure to prevent it from boiling, despite its high temperature.12
- Heat Exchange: The hot primary water is pumped into a steam generator, which acts as a heat exchanger.13
- Secondary Loop: Inside the steam generator, the heat from the primary loop is transferred to a separate, lower-pressure secondary water circuit. As the secondary water absorbs this thermal energy, it reaches saturation and turns into steam.12
This steam is then used as the working fluid to drive a steam turbine. Because the primary and secondary loops remain physically separated, the radioactive water in the primary loop does not contaminate the secondary circuit, provided the system's seals remain intact.132