Experimental Study of Turbulent Round Jet Discharged Into Regular Waves

Abstract

The present study is to investigate the mechanism of turbulent fluctuation between regular progressive wave and neutrally buoyant horizontal round jet experimentally. A Particle Image Velocimetry (PIV) technique was employed to measure the instantaneous velocity field of the turbulent jet under wave environment. The mean flow and RMS (Root-Mean-Square) velocity fluctuation were extracted using the phase-averaged method of all instantaneous velocity maps located at that spatial location. Three different incident wave heights were used to examine the effects of wave amplitude on the interactions of a turbulent jet with water waves. The agreement of our experimental data to the similar profiles suggested by previous studies was discussed. The experimental results showed that the jet widths of the mean flow and RMS velocity fluctuation were significantly increased and shifted when jet was under the wave environments. The wave phase has an insignificant influence on the mean velocity field, but it affects the turbulent fluctuation field when jet under different wave motion phase.