短语词组短語vortex x ring 渦環;漩渦之環vortex -ring cascade 渦環級聯vortex ring state 渦環狀態Incessant Vortex Ring 無盡渦環vortex ring canopy 渦環繖衣vortex ring effect 漩渦環傚應vortex ring state boundary 渦環狀態邊界 返回 vortex ring