ADVANCES IN INTERNAL WAVES DUE TO MOVING BODY IN STRATIFIED FLUID SYSTEMS

This article presents a brief review of the research workon both the Kelvin-wake and the non-Kelvin-wake generated by a submergedbody moving, respectively, in continuous and discontinuous densitystratification systems. The review lays its emphasis on analytical resultsand related experimental work in a stratified tank. The general governingequation for the non-Kelvin-wake in the continuously stratified fluid andthe potential-flow analysis for the Kelvin-wake in the discontinuouslystratified fluidare outlined. Three special internal waves, i.e., the precursor soliton,algebraic solitary wave and flat solitary wave, induced by a movingsource,are described, in which the internal flat solitary wave is shown to be atypical limiting solitary wave in experiments by the authors and then is firstformulated by a conjugate flow model. The complicated dynamicalcharacteristics in the internal wave generation due to a moving body inalinearly-distributed density fluid are summarized, including space-timestructures at near and far fields of wakes, instabilities, coupledconfigurations between vortex and turbulence and interactions betweeninternal wave and turbulence.