Measurements of Turbulent Flow in Transverse- or Angled-Rib-Roughened Stationary Channel by Using Two-Dimensional Particle Image Velocimetry
Hiroshi Saito, Akira Murata and Sadanari Mochizuki
This study experimentally deals with turbulent flow inside a straight rib-roughened duct in stationary condition. Details of the two-dimensional flow fields around transverse or angled ribs were quantitatively measured using particle image velocimetry (2D-PIV) with high spatial- and time-resolution. Flow separation, reattachment and recirculation behind the rib, small separation bubble in front of the rib, and secondary flow in the perpendicular cross section were observed. High turbulence intensity in the reattachment area and in front of the ribs, resulting from the highly fluctuating unsteady velocity vectors, was clearly captured. The results are relevant to internal forced convection cooling inside turbine blades.