Vortex Shedding from a Two-Dimensional Blunt Trailing Edge with Unequal External Free-Stream Velocities

Abstract

The frequency of vortex shedding from a two-dimensional blunt trailing edge of a plate was experimentally investigated when external free-stream velocities on both sides are not equal. Reynolds number Re (based on the thickness of the trailing edge and the mean velocity) ranged from 190 to 3, 000 and the low-to-high velocity ratio X was varied from 0 to 1.0. In the range K≥0.78, the relation between Strouhal number and Reynolds number was almost the same as that for the case where the ratio is unity. The level of Strouhal number was higher for K<0.78 than for K>0.78. The vortex-shedding patterns can be classified into four modes which are clarified in the Re-K domain. Moreover, the critical Reynolds number beyond which the vortex shedding from the blunt trailing edge occurs were obtained as a function of Re and K.