Numerical Studies in Two-dimensional Turbulence
Title | Numerical Studies in Two-dimensional Turbulence PDF eBook |
Author | Fayeza Salim Sulti |
Publisher | |
Pages | |
Release | 2012 |
Genre | |
ISBN |
Two-dimensional turbulence has been extensively studied over the past years theoretically and numerically since the theory of the dual cascade energy. Numerical studies have revealed an impor- tant feature of two-dimensional turbulence, that is, the predomi- nance of coherent structures, followed by interaction and merger of these isolated vortices in the subsequent evolution. A method of 'vortex census' has been introduced to keep track of the vortices but the relation to reconnection has remained unexplored. In this Thesis, we study the reconnection process of vorticity con- tours associated with coherent vortices in two-dimensional turbu- lence for different Reynolds number. After checking topological integrity by the Euler index theorem, we make use of the critical points and their connectivity (so-called surface networks) to study the topological changes of vorticity contours. Wc show how this method can remarkably distinguish the dynamics of the vortic- ity field in the Navier-Stokes equations and that of the Charney- Hasegawa-Mima equation. We found that the potential vorticity formed vortex crystals. This excites us to study the vortex crystal in details by study a coarse-grained asymptotic equation [Smirnov and Chukbar(2001)]. Self-similar blow-up solutions with an infi- 1 I i :. nite total energy were given. We ask whether or not finite-time blow-up can take place developing from smooth initial data with a finite energy.
Numerical Studies in Two-dimensional Turbulence
Title | Numerical Studies in Two-dimensional Turbulence PDF eBook |
Author | Fayeza Salim Al Sulti |
Publisher | |
Pages | 0 |
Release | 2013 |
Genre | |
ISBN |
Research Directions in Computational Mechanics
Title | Research Directions in Computational Mechanics PDF eBook |
Author | National Research Council |
Publisher | National Academies Press |
Pages | 145 |
Release | 1991-02-01 |
Genre | Technology & Engineering |
ISBN | 0309046483 |
Computational mechanics is a scientific discipline that marries physics, computers, and mathematics to emulate natural physical phenomena. It is a technology that allows scientists to study and predict the performance of various productsâ€"important for research and development in the industrialized world. This book describes current trends and future research directions in computational mechanics in areas where gaps exist in current knowledge and where major advances are crucial to continued technological developments in the United States.
Mathematics of Two-Dimensional Turbulence
Title | Mathematics of Two-Dimensional Turbulence PDF eBook |
Author | Sergei Kuksin |
Publisher | Cambridge University Press |
Pages | 337 |
Release | 2012-09-20 |
Genre | Mathematics |
ISBN | 113957695X |
This book is dedicated to the mathematical study of two-dimensional statistical hydrodynamics and turbulence, described by the 2D Navier–Stokes system with a random force. The authors' main goal is to justify the statistical properties of a fluid's velocity field u(t,x) that physicists assume in their work. They rigorously prove that u(t,x) converges, as time grows, to a statistical equilibrium, independent of initial data. They use this to study ergodic properties of u(t,x) – proving, in particular, that observables f(u(t,.)) satisfy the strong law of large numbers and central limit theorem. They also discuss the inviscid limit when viscosity goes to zero, normalising the force so that the energy of solutions stays constant, while their Reynolds numbers grow to infinity. They show that then the statistical equilibria converge to invariant measures of the 2D Euler equation and study these measures. The methods apply to other nonlinear PDEs perturbed by random forces.
Numerical Studies of Dispersion Processes in Two-dimensional, Homogeneous, Decaying Turbulence
Title | Numerical Studies of Dispersion Processes in Two-dimensional, Homogeneous, Decaying Turbulence PDF eBook |
Author | Anthony Daniel Kowalski |
Publisher | |
Pages | 248 |
Release | 1980 |
Genre | Dispersion |
ISBN |
Numerical Studies of Laminar and Turbulent Drag Reduction
Title | Numerical Studies of Laminar and Turbulent Drag Reduction PDF eBook |
Author | National Aeronautics and Space Administration (NASA) |
Publisher | Createspace Independent Publishing Platform |
Pages | 34 |
Release | 2018-08-13 |
Genre | |
ISBN | 9781725106895 |
Two-dimensional incompressible flow over wavy surfaces is studied numerically by spectral methods. Turbulence effects are modeled. Results for symmetric and asymmetric wave forms are presented. Effect of propagating surface waves on drag reduction is studied. Comparisons between computer simulations and experimental results are made. Balasubramanian, R. and Orszag, S. A. Unspecified Center NASA-CR-3498, CHI-57 NAS1-16237...
Mathematical and Physical Theory of Turbulence, Volume 250
Title | Mathematical and Physical Theory of Turbulence, Volume 250 PDF eBook |
Author | John Cannon |
Publisher | CRC Press |
Pages | 209 |
Release | 2006-06-15 |
Genre | Mathematics |
ISBN | 1420014978 |
Although the current dynamical system approach offers several important insights into the turbulence problem, issues still remain that present challenges to conventional methodologies and concepts. These challenges call for the advancement and application of new physical concepts, mathematical modeling, and analysis techniques. Bringing together ex