We prove two finite dimensional approximation results and a symplectic non-squeezing property for the Korteweg-de Vries (KdV) flow on the circle T. The nonsqueezing result relies on the aforementioned approximations and the finite-dimensional nonsqueezing theorem of Gromov [13]. Unlike the work of Kuksin [21] which initiated the investigation of non-squeezing results for infinite dimensional Ha...

Turbulent bursting events play a major role in natural systems in terms of sediment scour, transport and accretion as well as contaminant mixing and dispersion. The "bursts" were extensively studied in laboratory experiments under steady flow conditions, but rarely tested in unsteady natural flows. Herein a technique is described for the detection and analysis of turbulent events within large c...

Research in convective heat transfer using suspensions of nanometer-sized solid particles in base liquids started only over the past decade. Recent investigations on nanofluid, as such suspensions are often called, indicate that the suspended nanoparticles remarkably change the transport properties and heat transfer characteristics of the suspension. Bending walls can also improve heat transfer...

Effect of altitude is discussed in the unsteady separation of multi stage rockets. Axisymmetric, unsteady and turbulent Navier stokes equations are solved numerically. The governing equations are split into a hyperbolic inviscid part and a parabolic diffusion part. The hyperbolic part is solved by an explicit second-order time and space of Godunov-type scheme. Moving mesh and moving boundary al...

The flow and heat transfer inside a non-isothermal and incompressible thin film having its upper plate slightly inclined from the horizontal and undergoing an oscillatory squeezing motion is investigated in this work. Two models are analyzed: low and large Reynolds number flow models. The corresponding governing equations for each model are properly non-dimensionalized and solved numerically. T...

Simulation results on dynamic yaw stability derivatives of a gull bird by means of computational fluid dynamics are presented. Two different kinds of motions are used for determining the dynamic yaw stability derivatives Nr C and β& N C . Concerning the first one, simple lateral translation and yaw rotary motions in yaw are considered. The second one consists of combined motions. To determine d...

A hardware-based approach for visualizing unsteady flow fields by means of Lagrangian-Eulerian advection is presented. Both noise-based and dyebased texture advection is supported. The implementation allows the advection of each texture to be performed completely on the graphics hardware in a single-pass rendering. We discuss experiences with the interactive visualization of unsteady flow field...

We present dye visualizations of the flow generated by a sphere rolling along a solid surface in a quiescent fluid at low Reynolds numbers. Recent experimental and numerical studies of this configuration (Stewart et al. 2008, 2010) have shown a transition from steady to periodic flow at a Reynolds number Re (based on the sphere diameter and rolling speed) near 100. The unsteady flow involves th...

the unsteady flow in porous medium of a viscous incompressible fluid bounded by two parallel porous plates is studied with heat transfer. a uniform and constant pressure gradient is applied in the axial direction whereas a uniform suction and injection are applied in the direction normal to the plates. the two plates are kept at constant and different temperatures and the viscous dissipation is...