Author: John-Patrick Floyd (II.)
Publisher:
ISBN:
Category : Controlled fusion
Languages : en
Pages :
Get Book Here
Book Description
The presence of a large pinch velocity in the edge pedestal of high confinement (H-mode) tokamak plasmas implies that particle transport in the plasma edge ust be treated by a pinch-diffusion theory, rather than a pure diffusion theory. Momentum balance also requires the inclusion of a pinch term in descriptions of edge article transport. A numerical investigation of solving generalized pinch-diffusion theory using methods extended from the numerical solution methodology of pure iffusion theory has been carried out. The generalized diffusion equation has been numerically integrated using the central finite-difference approximation for the diffusion erm and three finite difference approximations of the pinch term, and then solved using Gauss reduction. The pinch-diffusion relation for the radial particle flux was solved directly and used as a benchmark for the finite-difference algorithm solutions to the generalized diffusion equation. Both equations are solved using several esh pacings, and it is found that a finer mesh spacing will be required in the edge pedestal, where the inward pinch velocity is large in H-mode plasmas, than is necessary or similar accuracy further inward where the pinch velocity diminishes. An expression for the numerical error of various finite-differencing algorithms is presented.
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 252
Get Book Here
Book Description
Author: Weihua Deng
Publisher: World Scientific
ISBN: 9813142227
Category : Mathematics
Languages : en
Pages : 295
Get Book Here
Book Description
The aim of this book is to extend the application field of 'anomalous diffusion', and describe the newly built models and the simulation techniques to the models.The book first introduces 'anomalous diffusion' from the statistical physics point of view, then discusses the models characterizing anomalous diffusion and its applications, including the Fokker-Planck equation, the Feymann-Kac equations describing the functional distribution of the anomalous trajectories of the particles, and also the microscopic model — Langevin type equation. The second main part focuses on providing the high accuracy schemes for these kinds of models, and the corresponding convergence and stability analysis.
Author: Jordan Hristov
Publisher: Nova Science Publishers
ISBN: 9781536184884
Category : Mathematics
Languages : en
Pages : 189
Get Book Here
Book Description
Diffusion is a principle transport mechanism emerging widely at different scale, from nano to micro and macro levels. This is a contributed book of seventh chapters encompassing local and no-local diffusion phenomena modelled with integer-order (local) and non-local operators. This book collates research results developed by scientists from different countries but with common research interest in modelling of diffusion problems. The results reported encompass diffusion problems related to efficient numerical modelling, hypersonic flows, approximate analytical solutions of solvent diffusion in polymers and wetting of soils. Some chapters are devoted to fractional diffusion problem with operators with singular and non-singular memory kernels. The book content cannot present the entire rich area of problems related to modelling of diffusion phenomena but allow seeing some new trends and approaches in the modelling technologies. In this context, the fractional models with singular and non-singular kernels the numerical methods and the development of the integration techniques related to the integral-balance approach form fresh fluxes of ideas to this classical engineering area of research.The book is oriented to researchers; master and PhD students involved in diffusion problems with a variety of application and could serves as a rich reference source and a collection of texts provoking new ideas.
Author:
Publisher:
ISBN:
Category : Hydrology
Languages : en
Pages : 810
Get Book Here
Book Description
Author: Iván Lux
Publisher:
ISBN:
Category :
Languages : en
Pages : 14
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category : Water
Languages : en
Pages : 412
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
A Primer of Diffusion Problems A Primer of Diffusion Problems is a concise and lively introduction to diffusion theory in its many guises and to a variety of analytical and numerical methods for the solution of diffusion problems. It discusses the diffusion equation, the steady state, diffusion under external forces, time-dependent diffusion, and similarity, thus bridging mathematical and physical treatments of diffusion. Featured topics include a careful development of the oxidation theory of silicon, properties of the family of error functions, precipitation and phase transformations, a concise introduction to Laplace transforms, and nonlinear boundary conditions. Exercises are found throughout the text, and appendices treat rarely found advanced topics.
Author: Dan M. Goebel
Publisher: John Wiley & Sons
ISBN: 0470436263
Category : Technology & Engineering
Languages : en
Pages : 528
Get Book Here
Book Description
Throughout most of the twentieth century, electric propulsion was considered the technology of the future. Now, the future has arrived. This important new book explains the fundamentals of electric propulsion for spacecraft and describes in detail the physics and characteristics of the two major electric thrusters in use today, ion and Hall thrusters. The authors provide an introduction to plasma physics in order to allow readers to understand the models and derivations used in determining electric thruster performance. They then go on to present detailed explanations of: Thruster principles Ion thruster plasma generators and accelerator grids Hollow cathodes Hall thrusters Ion and Hall thruster plumes Flight ion and Hall thrusters Based largely on research and development performed at the Jet Propulsion Laboratory (JPL) and complemented with scores of tables, figures, homework problems, and references, Fundamentals of Electric Propulsion: Ion and Hall Thrusters is an indispensable textbook for advanced undergraduate and graduate students who are preparing to enter the aerospace industry. It also serves as an equally valuable resource for professional engineers already at work in the field.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 26
Get Book Here
Book Description
