Impellor vs. Impeller — What's the Difference?

Impellor and impeller essentially refer to the same device within mechanical engineering—a rotor used to increase (or decrease in the case of turbines) the pressure and flow of a fluid. The term "impeller" is the more commonly used and recognized spelling in the majority of contexts, whereas "impellor" might be seen as an alternative, less common variation of the word. Both terms describe a component found in various machines such as pumps, fans, and compressors, designed to transfer energy from the motor that drives the device to the fluid being moved.

While there's no difference in function or design attributed to the spelling variation, "impeller" is preferred in technical and academic writing, reflecting standard terminology in the field of fluid dynamics. The key role of an impeller (or impellor) is to impart kinetic energy to the fluid, facilitating the desired movement or flow. This is achieved through the rotation of the impeller, which, due to its specific design and blade orientation, pushes the fluid outward from the center of rotation, thereby causing a flow.

The design of an impeller can vary widely depending on its intended application. For example, impellers used in pumps are designed to move liquids, while those in fans are intended to move gases. Despite the variation in application and design, the fundamental principle of operation remains the same—utilizing rotational energy to move or manipulate fluid flow.

One might encounter both spellings across different texts, manuals, or product descriptions, but it's important to understand that these variations do not imply a difference in function or type. Whether referred to as an impellor or an impeller, the device's role in facilitating fluid movement through rotational energy is consistent across applications.

The selection between "impellor" and "impeller" might come down to regional preferences, personal habit, or the specific conventions of a particular industry or company. However, for clarity and consistency, especially in formal engineering and academic contexts, "impeller" is the predominantly used terminology.