环形涡 meaning in English

ring vortex

The detachment of ring - like vortex from hair - pin vortex induces the breakdown of the head of hair - pin vortex . then the broken small vortex structures move towards the wall
环形涡的形成会引发发卡涡头部的破碎，破碎的小涡结构向壁面运动。
The head of hair - pin vortex rise to the center of the pipe and horse - shoe vortex is formed . then the horse - shoe vortex detaches from hair - pin vortex and form isolated ring - like vortex
首先发卡涡的头部在向圆管中心抬升的过程中，会形成马蹄涡，马蹄涡从发卡涡头部脱离后，形成孤立的环形涡。
When the psb amplitude is weak , a series of hair - pin vortex will be formed . the formation , diffusion , breakup of the front edge of hair - pin vortex and the break of the head of hair - pin vortex lead to the first instability and form the slug structure
在一定幅值的psb弱扰动作用下，圆管流动中出现一系列发卡涡，发卡涡前缘处环形涡的形成、扩散和破裂以及发卡涡头部的破碎导致了流动的第一次失稳，产生塞流结构。