Final answer:
A labyrinth seal uses a series of ridges to create a complex path, minimizing leakage in machinery without causing wear due to its non-contact design.
Step-by-step explanation:
Labyrinth seals on rotating shafts provide non-contact sealing action by controlling the passage of fluid through a variety of chambers by centrifugal motion, as well as by the formation of controlled fluid vortices. The type of seal that consists of a series of ridges creating an intricate path to prevent leakage is known as a labyrinth seal. Labyrinth seals are non-contact types of seals used in machinery, such as turbines and compressors, to minimize fluid leakage between sections of the machine where there is a significant differential in pressure.
The purpose of the ridges (also known as teeth or steps) is to create a complex path that makes it difficult for the fluid, typically gas or liquid, to pass through the seal. This resistance to fluid flow reduces leakage without causing wear on the seal because there is no direct contact between the moving parts and the seal itself.