摘要:The vortex shedding frequency in the mixing layer between a cavity and a main stream has been examined experimentally in absence of large oscillation of the free surface inside the cavity, called seiching. It was observed that the vortex shedding frequency follows a monotonically increasing trends with possible jumps from one to another with increasing Froude number of the main stream. These trends are obtained by solving a model based on the Rossiter approach. This model considers that the vortices shed in the mixing layer create some water depth variation at the impingement corner of the cavity. This water depth variation in turn generate pressure waves that propagates upstream and influence the vortex shedding process. Finally the measured vortex shedding frequencies correspond quite accurately to the frequencies predicted by the model. This highlights the existence of a resonant phenomena between vortices in the mixing layer of a lateral cavity and gravity waves even without any seiching phenomena.
其他摘要:The vortex shedding frequency in the mixing layer between a cavity and a main stream has been examined experimentally in absence of large oscillation of the free surface inside the cavity, called seiching. It was observed that the vortex shedding frequency follows a monotonically increasing trends with possible jumps from one to another with increasing Froude number of the main stream. These trends are obtained by solving a model based on the Rossiter approach. This model considers that the vortices shed in the mixing layer create some water depth variation at the impingement corner of the cavity. This water depth variation in turn generate pressure waves that propagates upstream and influence the vortex shedding process. Finally the measured vortex shedding frequencies correspond quite accurately to the frequencies predicted by the model. This highlights the existence of a resonant phenomena between vortices in the mixing layer of a lateral cavity and gravity waves even without any seiching phenomena.