Parameterization of Neutrally Buoyant Horizontal Round Jet in Wave Environment

Abstract

The present study is to parameterize the influence of regular progressive waves on the diffusion of a neutrally buoyant turbulent round jet experimentally. The jet, located at the middepth, discharges into the wave field horizontally in the direction against the wave propagation. The particle image velocimetry technique and the laser induced fluorescence technique were used to measure the velocity field and examine the jet cross-sectional profile. Three different wave periods with a range of wave amplitudes in each wave period were tested to investigate the effect of waves on jet diffusion. The wave conditions cover both the shallow water and deep water, whereas the wave slopes range from linear to weakly nonlinear. The results showed that the width of the jet was significantly affected by the waves. The wave dispersion enhanced the jet diffusion, especially for a larger wave slope and a shallower water depth. The results also showed that the wave-to-jet momentum ratio is the most important parameter to characterize the effect of waves to the diffusion of jet.