AD-P004 168 AD-P004 169 TITLE: Superroaneuverability. Wing Rock Flov Phenomena. Potential Applications of Forced Unsteady Flows. Unsteady Stall Penetration of an Oscillating Swept Wing. Simultaneous Flow Visualization and Unsteady Lift Measurement on an Oscillating Lifting Surface. A Visual Study of a Delta Wing in Steady and Unsteady Motion. Comparative Visualization of Accelerating Flow aroun...

Instantaneous streamlines are commonly used to visualize particle paths in steady flows. It is shown, however, that streaklines are often more appropriate for unsteady flows. The typical size of unsteady flow simulations makes interactive visualization difficult if not impossible. Two common approaches for visualizing unsteady flows are described. The advantages and disadvantages of each are di...

Analyzing vortices in fluid flows is an important and extensively studied problem. Visualization methods are an important tool, and vortex cores, including vortex-core axes, are frequently objects for which visualization is attempted. A robust definition of vortex-core axis has eluded researchers for a decade. This paper reviews the criteria described in some early papers, as well as recent pap...

Flow volumes [1] are extended for use in unsteady (timedependent) flows. The resulting unsteady flow volumes are the 3 dimensional analog of streaklines. There are few examples where methods other than particle tracing have been used to visualize time varying flows. Since particle paths can become convoluted in time there are additional considerations to be made when extending any visualization...

1. Introduction A great variety of flows with importance to practical engineering applications are inherently unsteady and virtually all of the Newtonian fluid flows in nature are turbulent. Therefore, it is natural and unavoidable to deal with unsteady turbulent flows when Computational Fluid Dynamics (CFD) techniques are applied to engineering design and industrial use. CFD for general fluid ...

flood routing has many applications in engineering projects and helps designers in understanding the flood flow characteristics in river flows. floods are taken unsteady flows that vary by time and location. equations governing unsteady flows in waterways are continuity and momentum equations which in case of one-dimensional flow the saint-venant hypothesis is considered. dynamic wave model as ...

Unsteady viscous flows and Stokes’s first problem are examined. Three problems are considered: unsteady Couette flow, unsteady Poiseuille flow, and unsteady boundary layer flow. The relationship between these three fundamental unsteady flows and Stokes’ first problem is illustrated. Scaling principles are used to deduce the short time and long time characteristics of these three problems. Asymp...

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...

In engineering practice, the unsteady flows generated from the operation of hydropower station in the upstream region could significantly change the navigation system of waterways located in the middle-lower reaches of the river. In order to study the complex propagation, convergence and superposition characteristics of unsteady flows in a long channel with flow confluence, a numerical model ba...

The work presents an artificial compressibility method applied to incompressible Navier-Stokes equations for steady as well as for unsteady flows. Two modifications of unsteady numerical solution by an implicit finite volume method are considered. First one uses large artificial compressibility parameter and the iterative solution approximates unsteady evolution of flow. The second approach int...