Author: P.S. BeranPublisher:
ISBN:
Category :
Languages : en
Pages : 13
Book Description
Numerical Simulations of Trailing Vortex Bursting
Author: P.S. BeranAn Investigation of the Bursting of Trailing Vortices Using Numerical Simulation
Author: Philip Stewart BeranPublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 342
Book Description
Numerical Simulation of Leading-edge Vortex Rollup and Bursting
Author: Steven Allan BrandtPublisher:
ISBN:
Category :
Languages : en
Pages : 210
Book Description
Vortex aerodynamics has played an important role in the development of high performance aircraft in recent years. Although computer codes which solve the three dimensional Euler equations have been used extensively to study leading-edge vortices, they don't include physical viscosity effects associated with vortex flows. The Euler solvers do, however, contain numerical viscosity. As a result, viscosity effects in the Euler solutions such as vortex core size, vortex burst location, leading edge separation, and vortex rollup often do not agree quantitatively with results of physical experiments. The present work defines models for these physical viscosity effects which can be coupled with an Euler solver to improve modeling of vortex physics. A vortex core model is derived from the steady, incompressible Navier-Stokes equations written in cylindrical coordinates. The core model is coupled with an Euler solver and tested on a variety of delta wings over a range of angles of attack. The resulting surface pressure distributions and vortex burst locations are shown to be much closer than results from Euler codes alone. Theses. (jhd).
Direct Numerical Simulations of Highly Vortical Flows and Vortex Breakdown
Author: Wing Tsin MaNumerical Simulation of Vortex Breakdown
Author: Jasim Uddin AhmadPublisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 318
Book Description
Vortex wakes of Aircrafts
Author: A.S. GinevskyPublisher: Springer Science & Business Media
ISBN: 3642017606
Category : Mathematics
Languages : en
Pages : 166
Book Description
Investigation of vortex wakes behind various aircraft, especially behind wide bodied and heavy cargo ones, is of both scientific and practical in terest. The vortex wakes shed from the wing’s trailing edge are long lived and attenuate only atdistances of10–12kmbehindthe wake generating aircraft. The encounter of other aircraft with the vortex wake of a heavy aircraft is open to catastrophic hazards. For example, air refueling is adangerous operationpartly due to thepossibility of the receiver aircraft’s encountering the trailing wake of the tanker aircraft. It is very important to know the behavior of vortex wakes of aircraft during theirtakeoff andlanding operations whenthe wakes canpropagate over the airport’s ground surface and be a serious hazard to other depart ing or arriving aircraft. This knowledge can help in enhancing safety of aircraft’s movements in the terminal areas of congested airports where the threat of vortex encounters limits passenger throughput. Theoreticalinvestigations of aircraft vortex wakes arebeingintensively performedinthe major aviationnations.Usedforthispurpose are various methods for mathematical modeling of turbulent flows: direct numerical simulation based on the Navier–Stokes equations, large eddy simulation using the Navier–Stokes equations in combination with subrigid scale modeling, simulation based on the Reynolds equations closed with a differential turbulence model. These approaches are widely used in works of Russian and other countries’ scientists. It should be emphasized that the experiments in wind tunnels and studies of natural vortex wakes behind heavy and light aircraft in flight experiments are equally important.
Numerical Studies of Three-dimensional Breakdown in Trailing Vortex Wakes
Author: Fluid Vortices
Author: Sheldon GreenPublisher: Springer Science & Business Media
ISBN: 940110249X
Category : Technology & Engineering
Languages : en
Pages : 905
Book Description
Fluid Vortices is a comprehensive, up-to-date, research-level overview covering all salient flows in which fluid vortices play a significant role. The various chapters have been written by specialists from North America, Europe and Asia, making for unsurpassed depth and breadth of coverage. Topics addressed include fundamental vortex flows (mixing layer vortices, vortex rings, wake vortices, vortex stability, etc.), industrial and environmental vortex flows (aero-propulsion system vortices, vortex-structure interaction, atmospheric vortices, computational methods with vortices, etc.), and multiphase vortex flows (free-surface effects, vortex cavitation, and bubble and particle interactions with vortices). The book can also be recommended as an advanced graduate-level supplementary textbook. The first nine chapters of the book are suitable for a one-term course; chapters 10--19 form the basis for a second one-term course.
Author: Saad Ragab
Author: Miguel R. Visbal