层流

层流	céng liú	laminar flow
层	céng	to pile on top of one another / layer; stratum / floor (of a building); story / (math.) sheaf / classifier for layers
流	liú	to flow / to disseminate / to circulate or spread / to move or drift / to degenerate / to banish or send into exile / stream of water or sth resembling one / class, rate or grade