What is the geometric shape of the pump casing known as?

The pump casing is known as a volute, which is a spiral-shaped structure designed to efficiently convert the kinetic energy of the fluid being pumped into pressure energy. The unique geometry of the volute plays a critical role in minimizing turbulence and ensuring smooth flow as the fluid exits the pump, thus optimizing performance and efficiency. This design allows for even distribution of fluid velocity, which is essential for the effective operation of centrifugal pumps.

In contrast, the other terms do not accurately describe the pump casing. A reservoir is typically meant to hold a supply of water or fluid but is not directly related to the pump's casing design. A cylinder often refers to a simple geometric shape that can describe various components but lacks the specific functional characteristics associated with a pump casing. A chamber may refer to any enclosed space but doesn't specifically denote the shape and function integral to a pump's operation like a volute does. The volute's design is critical for the effective operation of pumps in moving fluids efficiently and maintaining their desired pressure levels.