Which function do moving blades in a reaction turbine serve?

The primary function of the moving blades in a reaction turbine is to convert some of the heat energy of the steam or fluid into kinetic energy, facilitating the generation of mechanical energy as the fluid passes through the turbine. This process involves the movement of the blades, which interact with the high-velocity fluid to extract energy efficiently.

In addition to this crucial role, the moving blades also contribute to increasing the absolute velocity of the fluid as it travels through the turbine. Together with the fixed blades that precede them, the moving blades ensure that the pressure drop occurs across the blades, creating an acceleration of the fluid.

Furthermore, while the moving blades can have a nozzle-like profile to facilitate this acceleration, their primary function is energy conversion rather than simply shaping as nozzles.

Although it might seem reasonable to include all options as correct, the essence of the inquiry is focused on the conversion of energy, which is the central purpose of the moving blades in a reaction turbine. The other aspects, while true, are secondary to the main function, and thus the correct focus is on the primary mechanism of energy conversion in the turbine.