Turbulent energy transport of a jet in stagnant or wave environment

The main purpose of this study is to investigate the turbulence characteristics of a non-buoyant jet discharged vertically in steady conditions and beneath a regular wave field. A LDA system was developed to measure simultaneously the two dimensional velocity field. The turbulent micro and integral scales were determined at different cross sections. The results show that the production of turbulent kinetic energy is primarily used for dissipation and secondarily to increase the turbulent kinetic energy of the entrained mass for jets in a stagnant ambient or in a wave environment. This balance is different from the one of immiscible flows. The characteristic behaviour of turbulence is closely related to entrainment, which may be vortex-generated (jet, plume, etc.) or cusp-generated (free surface buoyant flow, dense bottom current, etc.).