Most previous studies about chaotic mixing focused on time-periodic or spatialy-periodic flows.In contrary,fewer studies have been done in aperiodic flows.In this paper,the chaotic mixing generated by periodic and ape...Most previous studies about chaotic mixing focused on time-periodic or spatialy-periodic flows.In contrary,fewer studies have been done in aperiodic flows.In this paper,the chaotic mixing generated by periodic and aperiodic flows is investigated through visible experiments and numerical simulations.The distribution of stretching is found to be much more uniform for apeiodic flows and mixing efficiency of aperiodic flows is higher than periodic flows.Among the several aperiodic sequences,the SB sequence is the best one.展开更多
In this paper the flow field in a static mixer is measured by Particle Image Velocimetry (PIV), which belongs to the technique of flow visualization. The vorticity field is obtained from the velocity field. The sequen...In this paper the flow field in a static mixer is measured by Particle Image Velocimetry (PIV), which belongs to the technique of flow visualization. The vorticity field is obtained from the velocity field. The sequences of particle images are analyzed statistically and the mixing homogeneity degrees are also determined by calculating probability densities. The relation between the mixing result is also related to the state of flow. The experiment show that the mixing is mainly affected by the motion of vortices, not turbulence diffusion.展开更多
文摘Most previous studies about chaotic mixing focused on time-periodic or spatialy-periodic flows.In contrary,fewer studies have been done in aperiodic flows.In this paper,the chaotic mixing generated by periodic and aperiodic flows is investigated through visible experiments and numerical simulations.The distribution of stretching is found to be much more uniform for apeiodic flows and mixing efficiency of aperiodic flows is higher than periodic flows.Among the several aperiodic sequences,the SB sequence is the best one.
文摘In this paper the flow field in a static mixer is measured by Particle Image Velocimetry (PIV), which belongs to the technique of flow visualization. The vorticity field is obtained from the velocity field. The sequences of particle images are analyzed statistically and the mixing homogeneity degrees are also determined by calculating probability densities. The relation between the mixing result is also related to the state of flow. The experiment show that the mixing is mainly affected by the motion of vortices, not turbulence diffusion.
