What is the relationship between the head produced by a centrifugal pump and impeller speed?

The relationship between the head produced by a centrifugal pump and the impeller speed varies quadratically. This is based on the principles of pump performance, where the head (H) generated by the pump is influenced by the rotational speed (N) of the impeller. Specifically, if the speed of the impeller is doubled, the head produced by the pump increases by a factor of four, which is a characteristic of quadratic relationships.

This quadratic relationship arises because head is proportional to the square of the velocity of the fluid, which in turn is affected by the impeller speed. The equation governing this relationship can be expressed as H ∝ N², illustrating how changes in speed lead to proportional changes in the generated head. Understanding this relationship is crucial for power engineers when designing and operating pump systems to ensure efficiency and proper performance under varying conditions.