Author(s): Y. P. Chen; C. W. Li; J. H. W. Lee
Linked Author(s): Chi Wai Li
Keywords: Jets; Random waves
Abstract: Wind waves frequently occur at the water surface of an inland or coastal water body. They are random and the associated energy is generally represented as a spectrum. For outfall jet discharge into coastal areas of shallow depth, these waves will affect the trajectory and enhance the mixing of the jet. To quantitatively investigate the effect of random waves on the jet discharge, laboratory experiments are conducted in a random wave flume. A round jet is installed at the bottom of the flume and is discharged vertically. Progressive random waves of different amplitudes and periods are generated. Velocity and turbulence intensity profiles at different elevations are measured by an Acoustic Doppler Velocimeter (ADV). Compared with the case of jet discharge into stagnant ambience, the lateral width of the jet and the averaged dilution of the present case are increased due to the additional wave induced entrainment. For the range of wave parameters tested, the jet width is increased by 20% and the averaged dilution is increased with its power relationship with the distance changed from 1 to 1.2, while the centerline velocity of the jet is only slightly affected.