Abstract
Experimental studies of turbulent flowfields developing over a heated riblet surface were carried out in a low-speed wind tunnel. A paritcle image velocimetry was used to measure the instantaneous velocity field. In the present study, it was found that the skin friction coefficient over a heated riblet surface reached up to about 13%. The mean-velocity profile in the law of the wall coordinate was shifted upward, which fact suggested a reduction in turbulence production in the near-wall region. This phenomenon was also shown by the characteristics of turbulence intensities observed over the riblet surface. Furthermore, instantaneous velocity vector map indicates that a perturbation of the spanwise veclocity component was restricted near the riblet surface.
