An approximation method of Moore for Kelvin-Helmholtz instability is formulated as a general method for two-dimensional, incompressible, inviscid flows generated by a vortex sheet. In this method the nonlocal equations describing evolution of the sheet are approximated by a system of (local) differential equations. These equations are useful for predicting singularity formation on the sheet and...

Abstract The influence of bottom roughness on the development lock-release gravity currents is investigated through laboratory experiments using Particle Image Velocimetry. represented by arrays vertical LEGO bricks with a constant spacing while varying $$\lambda $$ ? , relative height elements to current dep...

A large-eddy simulation has been performed to study the temporal and spatial dynamics of a rotor tip-clearance flow, with the objective of determining the underlying mechanisms for low pressure fluctuations downstream of the tip-gap. Simulation results are compared with experimental measurements, and favorable agreements are observed in both qualitative and quantitative sense. Typical vortical ...

Statement of problem on vortical inviscid flow of barotropic and incompressible fluids. Abstract The question what information is necessary for determination of a unique solution of hydrodynamic equations for ideal fluid is investigated. Arbitrary inviscid flows of the barotropic fluid and of incompressible fluid are considered. After integrating hydrodynamic equations, all information on the f...

We analyse the currently popular vortex identification criteria that are based on pointwise analysis of the velocity gradient tensor. A new measure of spiralling compactness of material orbits in vortices is introduced and using this measure a new local vortex identification criterion and requirements for a vortex core are proposed. The interrelationships between the different criteria are expl...

A theory is described for propagation of vortical waves across alternate rigid and compliant panels. The structure in the fluid side at the junction of panels is a highly vortical narrow viscous structure which is idealized as a wave driver. The wave driver is modelled as a ‘half source cum half sink’. The incoming wave terminates into this structure and the outgoing wave emanates from it. The ...