reaction turbine

A reaction turbine is a type of turbine where torque is developed from the gradual decrease of steam pressure from inlet to exhaust. Unlike impulse turbines, where steam expands in stationary nozzles before hitting the blades, in a reaction turbine, about half of the pressure drop and expansion occurs in the stationary passages and the other half in the rotor passages. This pressure change in the rotor passages creates a force that turns the wheel.12

Reaction turbines are commonly used in steam turbines for generating electricity and in water turbines for hydroelectric installations, particularly for moderate to high flow rates and heads below approximately 450 meters. A key design consideration for reaction turbines is preventing cavitation, a phenomenon where low pressure can cause water to vaporize into bubbles, leading to erosion and vibrations.34