Variational mode decomposition for estimating critical reflected internal wave in stratified fluid

Internal gravity wave radiation into weakly stratified fluid

It is shown by way of nonlinear numerical simulations of flow restricted to two dimensions that a compact wavepacket of large-amplitude internal gravity waves incident upon a weakly stratified region in which the buoyancy frequency is less than the frequency of the wavepacket may partially transmit energy into this region through the generation of a wavepacket of lower frequency. In part, the t...

Intrusive Gravity Currents and Internal Gravity Wave Generation in Stratified Fluid

The excitation of internal gravity waves by fluid intrusions that propagate along the interface between a uniform upper layer and a uniformly stratified lower layer is examined by way of laboratory experiments. Intrusions are generated using a simple lock-release apparatus. Experiments are conducted in which the density gradient of the uniformly stratified layer, the density jump across the int...

The axisymmetric collapse of a mixed patch and internal wave generation in uniformly stratified rotating fluid

We present an experimental and numerical investigation of the effect of Coriolis forces on the axisymmetric collapse of a uniform mixed region in uniformly stratified fluid. Laboratory experiments were performed on a rotating table in which a mixed patch contained initially in a hollow cylinder was released and so excited internal waves whose properties were analyzed using synthetic schlieren. ...

Observation of near-critical reflection of internal waves in a stably stratified fluid

Turbulence transition and internal wave generation in density stratified jets

The nonlinear evolution of an unstable symmetric jet in incompressible, density stratified fluid is simulated numerically. When N2 is constant and near zero, like-signed vortices pair by way of an instability of the mean Ilow to a subharmonic disturbance with wavelength twice that of the most unstable mode of linear theory. For small but finite and constant values of N2, however, the individual...