摘要
An experimental system for forming a rotating paraboloid shaped shallow water with a free surface was conducted to study coherent vortex structures in a differentially rotating quasi two dimensional zonal flow.Flow visualization and laser light scattering techniques were used to obtain the information of spatial flow patterns.Experimental results show that the coexistence of Coriolis effect and strong shear in latitudinal zones may lead to formation of coherent vortices.Power spectra analysis and photographs which were taken in a reference frame rotating with the observed vortices also justified the emergence,drift and evolution of persistent vortices on the large scale.Locked vortex state manifests the cyclone and anticyclone asymmetry.
建立具有自由表面的旋转抛物面浅水系统，以研究差动旋转准二维环带流中的相干涡旋结构．利用流动显示和激光散射技术获得了空间流动图样的信息．实验结果表明，在环带区存在科氏力和强剪切可能导致形成相干涡旋．在旋转随动坐标系中拍摄的照片和功率谱分析证实，确有大尺度持续存在的涡旋发生、漂移和演化．锁定的涡旋态表明气旋和反气旋呈非对称性．
