Flow Visualization around a Car Mirror

The aerodynamic noise and drag are associated with the flow structures and the unsteady behavior of the vortex causes the wind noise. However, litter attention has been paid to the complex vortical structures around externally mounted car mirror from the measured data. In this paper the turbulent structure of mirror wake has been experimentally investigated. The flow structures of the mirror wake were first visualized by the smoke-wire technique. The shedding vortices that are produced by two side of the mirror edge were clearly visualized. Then the instantaneous velocity fields were measured using PIV technique at Reynolds number of 6300. Instantaneous and mean streamlines, vorticity contours and Reynolds stresses were examined. The separation bubble and the region of the reverse flow behind the mirror were observed.