Which energy conversion occurs in the volute of a centrifugal pump?

• A. Kinetic energy is converted to flow energy
• B. Flow energy is converted to kinetic energy
• C. Thermal energy is converted to electrical energy
• D. Chemical energy is converted to magnetic energy

Answer: (A)

In a centrifugal pump, the volute around the impeller is designed to recover the energy of the fluid’s motion and convert it into pressure energy. When the fluid exits the impeller, it has high velocity (high kinetic energy). The volute’s increasing cross-sectional area slows the flow, reducing the velocity head while the pressure rises. This transfer of energy from motion to pressure is how the pump increases the fluid’s pressure so it can be delivered through the discharge system. So the best description is that kinetic energy is converted to flow energy (pressure energy) by the volute.

Other options don’t fit because the volute isn’t converting thermal energy to electrical energy, nor chemical energy to magnetic energy, and it doesn’t convert flow energy into kinetic energy; it actually reduces velocity to boost pressure.