114. Labyrinth seals are used on rotating steam turbine shafts to reduce external leakage. How is this accomplished?

Labyrinth seals minimize leakage by forcing steam through multiple small clearances, creating successive pressure drops across each stage. Each clearance acts as a throttling point, reducing pressure and limiting flow. This stepwise pressure reduction, not temperature changes, increased turbulence, or pressure increases, is the fundamental principle of labyrinth seal operation.