Experiments on effective tripping device in a zero pressure gradient turbulent boundary layer

Laminar-turbulent transition for flow over a flat plate can artificially be excited by introducing a tripping device. This will promote early transition in the boundary layer; hence a turbulent boundary layer can be realized at low Reynolds number. In this work, we consider three different types of tripping device, i.e. a circular rod, a square rod and a zigzag trip. Height of these three trips has been maintained same, i.e. 2 mm. Hotwire measurements have been carried out at several streamwise locations behind these trips. Measured flow characteristics behind these tripping devices have been presented in terms of recently suggested diagnostic plots along with the streamwise normal stress scaled by inner variables, and an effort has been made to characterize the best tripping device.