Two-dimensional Velocity Measurement Downstream of the Double Bend Pipe using Phased Array Ultrasonic Velocity Profiler

Abstract

In the present study, an experimental investigation is performed to obtain two-dimensional velocity field of the turbulent flow through the double bend pipe outlet. The main objective of the study is to investigate the velocity fluctuation in the recirculating flow region on the double bend pipe layout. Phased Array Ultrasonic Velocity Profiler is applied to obtain two-dimensional velocity field in a turbulent flow condition. In a water circulation piping system, the experiments are conducted in the turbulent flow condition, Reynolds number Re = 10,000. The measurement positions are located x/D = 1 and 1.5 (D = 50 mm) downstream of the double bent pipe outlet. Two-dimensional velocity field from the measurement result of Phased Array is compared with Particle Image Velocity (PIV) method. The reattachment point of the recirculating flow is found at the position x/D = 1. The axial and radial velocity fluctuations are analyzed near the reattachment point. The flow distortion and flow-accelerated phenomenon occur at the measurement positions downstream of the double bend pipe outlet.