短语词组短语vortex x ring 涡环;漩涡之环vortex -ring cascade 涡环级联vortex ring state 涡环状态Incessant Vortex Ring 无尽涡环vortex ring canopy 涡环伞衣vortex ring effect 漩涡环效应vortex ring state boundary 涡环状态边界 返回 vortex ring