What is the primary function of the propulsion turbines?

The primary function of the propulsion turbines is to turn steam into power, specifically mechanical energy that drives the ship's propellers. In a naval vessel, particularly one powered by a nuclear reactor, steam is produced in the reactor's steam generators. This steam is then routed to the turbines, where it causes the turbine blades to rotate. This mechanical energy is ultimately converted into thrust through the ship's propulsion system, allowing the ship to move through the water.

While turning steam into power is a critical part of the propulsion system, other options pertain to different processes or systems aboard the ship. The conversion of fuel into thermal energy occurs in the reactor, but this process is separate from the direct function of the propulsion turbines, which specifically harness that energy to produce mechanical power. Similarly, generating freshwater is done by other systems in the ship, such as evaporators or reverse osmosis units. As for controlling the ship's speed, this is an application of the power generated by the propulsion turbines rather than a direct function of the turbines themselves. The turbines provide the necessary power, and speed control is achieved through throttle management and propeller adjustments.