| An experimental investigation of fully-developed augmented convection in an isothermal, symmetrically grooved channel is performed for channel Reynolds numbers ranging from 800 to 5000. Grooves are of triangular shape and oriented transverse to the flow. The triangular geometry is designed to excite normally-damped Tollmien-Schlichting modes resulting in early transition to three-dimensional unsteady flow. Air is used as the working fluid.; The measurements of temperature fields and local heat transfer are performed using a holographic interferometer. Interferograms, representative of the cross-span-average temperature of the air in the channel, are analyzed to produce data of the air temperature distribution and the local heat flux along the groove faces. Heat flux distributions along the groove faces are non-uniform. The heat transfer coefficient of the windward face is approximately twice that of the leeward face. The overall heat transfer of the groove increases with the Reynolds number. The heat transfer coefficients become higher than the equivalent flat channel values when Re {dollar}>{dollar} 450, and this heat transfer augmentation appears to be maintained to approximately Re = 10{dollar}sp4.{dollar}... |
