Impulse turbines are defined by which of the following characteristics?

Impulse turbines primarily function through the principle of converting kinetic energy from high-velocity jets of steam or water into mechanical energy. One of the defining characteristics of impulse turbines is that they do not experience a pressure drop through the moving blades. Instead, the pressure is converted into velocity before it strikes the blades; therefore, the working fluid expands in the nozzles to create high-speed jets that drive the turbine.

In impulse turbines, the energy transfer occurs at the point of impact between the jet of fluid and the blades, making it crucial that the pressure remains almost constant as the fluid passes through the turbine blades. This results in a situation where the impulse created by the fluid is what propels the turbine, rather than a significant drop in pressure across the blades themselves.

This characteristic distinguishes impulse turbines from other types, such as reaction turbines, where pressure changes occur throughout the turbine as fluid flows through its various components. Understanding this distinction is key for anyone studying turbine operations in the context of power engineering.