Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Three Dimensional High Resolution Simulations Of Rayleigh Taylor Instability And Turbulent Mixing
Download Three Dimensional High Resolution Simulations Of Rayleigh Taylor Instability And Turbulent Mixing full books in PDF, epub, and Kindle. Read online Three Dimensional High Resolution Simulations Of Rayleigh Taylor Instability And Turbulent Mixing ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Three-dimensional High-resolution Simulations of Rayleigh-Taylor Instability and Turbulent Mixing by :
Download or read book Three-dimensional High-resolution Simulations of Rayleigh-Taylor Instability and Turbulent Mixing written by and published by . This book was released on 1997 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Preliminary results of three-dimensional simulations of compressible Rayleigh-Taylor instability and turbulent mixing in an ideal gas using the piecewise-parabolic method (PPM) (with and without molecular dissipation terms) are presented. Simulations with spatial resolutions up to 5123 were performed. Two types of convergence studies are presented. Statistical analyses of the data are discussed, include: 1: spectra, and; 2) horizontally-averaged terms in the kinetic energy and onstrophy density evolution equations. The application of this statistical data to the development and testing of subgrid-scale models appropriate for compressible Rayleigh-Taylor instability-induced turbulent mixing is discussed.
Book Synopsis Three-dimensional High-resolution Simulations of Compressible Rayleigh-taylor Instability and Turbuelnt Mixing by :
Download or read book Three-dimensional High-resolution Simulations of Compressible Rayleigh-taylor Instability and Turbuelnt Mixing written by and published by . This book was released on 1997 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Preliminary results of three-dimensional simulations of compressible Rayleigh-Taylor instabilities and turbulent mixing in an ideal gas using the piecewise-parabolic method (PPM) with and without molecular dissipation terms are presented. Simulations with spatial resolutions up to 512 were performed. Two types of convergence studies are presented. The first investigates the Reynolds numbers for which the simulations with molecular dissipation are converged with respect to spatial resolution, and the second investigates whether PPM simulations at different spatial resolutions reproduce fully-resolved PPM simulations with molecular dissipation. Finally, statistical analyses of the data are discussed, including spectra and horizontally-averaged terms in the kinetic energy and enstrophy density evolution equations. The application of this statistical data to the development and testing of subgrid-scale models appropriate for compressible Rayleigh-Taylor instability-induced turbulent mixing is discussed.
Book Synopsis Comparison of Two- and Three-dimensional Simulations of Miscible Rayleigh-Taylor Instability by :
Download or read book Comparison of Two- and Three-dimensional Simulations of Miscible Rayleigh-Taylor Instability written by and published by . This book was released on 2006 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comparison of two-dimensional and three-dimensional high-resolution numerical large-eddy simulations of planar, miscible Rayleigh-Taylor instability flows are presented. The resolution of the three-dimensional simulation is sufficient to attain a fully turbulent state. A number of different statistics from the mixing region (e.g., growth rates, PDFs, mixedness measures, and spectra) are used to demonstrate that two-dimensional flow simulations differ substantially from the three-dimensional one. It is found that the two-dimensional flow grows more quickly than its three-dimensional counterpart at late times, develops larger structures, and is much less well mixed. These findings are consistent with the concept of inverse cascade in two-dimensional flow, as well as the influence of a reduced effective Atwood number on miscible flow.
Book Synopsis Advances in Compressible Turbulent Mixing by :
Download or read book Advances in Compressible Turbulent Mixing written by and published by . This book was released on 1992 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Three Dimensional Hydrodynamic Calculations with Adaptive Mesh Refinement of the Evolution of Rayleigh Taylor and Richtmyer Meshkov Instabilities in Converging Geometry by :
Download or read book Three Dimensional Hydrodynamic Calculations with Adaptive Mesh Refinement of the Evolution of Rayleigh Taylor and Richtmyer Meshkov Instabilities in Converging Geometry written by and published by . This book was released on 1993 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present results for high resolution hydrodynamic calculations of the growth and development of instabilities in shock driven imploding spherical geometries in both 2D and 3D. They solve the Eulerian equations of hydrodynamics with a high order Godunov approach using local adaptive mesh refinement to study the temporal and spatial development of the turbulent mixing layer resulting from both Richtmyer Meshkov and Rayleigh Taylor instabilities. The use of a high resolution Eulerian discretization with adaptive mesh refinement permits them to study the detailed three-dimensional growth of multi-mode perturbations far into the non-linear regime for converging geometries. They discuss convergence properties of the simulations by calculating global properties of the flow. They discuss the time evolution of the turbulent mixing layer and compare its development to a simple theory for a turbulent mix model in spherical geometry based on Plesset's equation. Their 3D calculations show that the constant found in the planar incompressible experiments of Read and Young's may not be universal for converging compressible flow. They show the 3D time trace of transitional onset to a mixing state using the temporal evolution of volume rendered imaging. Their preliminary results suggest that the turbulent mixing layer loses memory of its initial perturbations for classical Richtmyer Meshkov and Rayleigh Taylor instabilities in spherically imploding shells. They discuss the time evolution of mixed volume fraction and the role of vorticity in converging 3D flows in enhancing the growth of a turbulent mixing layer.
Book Synopsis Turbulence and Instabilities by : O.M. Belotserkovskii
Download or read book Turbulence and Instabilities written by O.M. Belotserkovskii and published by . This book was released on 2000 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Monograph presents the newest results in the numerical modeling and computer simulation of turbulence.
Book Synopsis Rayleigh-Taylor Instability-induced Mixing by :
Download or read book Rayleigh-Taylor Instability-induced Mixing written by and published by . This book was released on 2007 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: A spectral/compact finite-difference method with a third-order Adams-Bashforth-Moulton time-evolution scheme is used to perform a direct numerical simulation (DNS) of Rayleigh-Taylor flow. The initial conditions are modeled by parameterizing the multi-mode velocity and density perturbations measured just off of the splitter plate in water channel experiments. Parameters in the DNS are chosen to match the experiment as closely as possible. The early-time transition from a weakly-nonlinear to a strongly-nonlinear state, as well as the onset of turbulence, is examined by comparing the DNS and experimental results. The mixing layer width, molecular mixing parameter, vertical velocity variance, and density variance spectrum obtained from the DNS are shown to be in good agreement with the corresponding experimental values.
Book Synopsis Compressible Turbulent Mixing - Proceedings Of Fifth International Workshop by : R Young
Download or read book Compressible Turbulent Mixing - Proceedings Of Fifth International Workshop written by R Young and published by World Scientific. This book was released on 1996-11-22 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this volume, compressible turbulent mixing is discussed from the viewpoints of experiment, numerical simulation and theoretical models. The major problem areas include Rayleigh-Taylor and Richtmyer-Meshkov instabilities, and multiphase mixing problems. A variety of initial configurations are discussed, including single and multiple mode perturbations and nonlinear geometries in both two and three dimensions. The effects of experimental and numerical artifacts are also considered.
Book Synopsis Hydrodynamic Instabilities and Turbulence by : Ye Zhou
Download or read book Hydrodynamic Instabilities and Turbulence written by Ye Zhou and published by Cambridge University Press. This book was released on 2024-05-31 with total page 611 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first comprehensive reference guide to turbulent mixing driven by Rayleigh-Taylor, Richtmyer-Meshkov and Kelvin-Helmholtz instabilities.
Book Synopsis Rayleigh-Taylor Mixing by : Andrew Lawrie
Download or read book Rayleigh-Taylor Mixing written by Andrew Lawrie and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Rayleigh-Taylor instability has been an area of active research in fluid dynamics for the last twenty years, but relatively little attention has been paid to the dynamics of problems where Rayleigh-Taylor instability plays a role, but is only one component of a more complex system. Here, Rayleigh-Taylor instability between miscible fluids is examined in situations where it is confined by various means: by geometric restriction, by penetration into a stable linear stratification, and by impingement on a stable density interface. Water-based experiments are modelled using a variety of techniques, ranging from simple hand calculation of energy exchange to full three-dimensional numerical simulation. Since there are well known difficulties in modelling unconfined Rayleigh-Taylor instability, the confined test cases have been sequenced to begin with dynamically simple benchmark systems on which existing modelling approaches perform well, then they progress to more complex systems and explore the limitations of the various models. Some work on the phenomenology of turbulent mixing is also presented, including a new experimental technique that allows mixed fluid to be visualised directly, and an analysis of energy transport and mixing efficiency in variable density flows dominated by mixing.
Book Synopsis Coarse Grained Simulation and Turbulent Mixing by : Fenando F. Grinstein
Download or read book Coarse Grained Simulation and Turbulent Mixing written by Fenando F. Grinstein and published by Cambridge University Press. This book was released on 2016-06-30 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews our current understanding of the subject. For graduate students and researchers in computational fluid dynamics and turbulence.
Book Synopsis Statistical Hydrodynamic Models for Developed Mixing Instability Flows by : Antoine Llor
Download or read book Statistical Hydrodynamic Models for Developed Mixing Instability Flows written by Antoine Llor and published by Springer Science & Business Media. This book was released on 2005-12-23 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part textbook, part exploratory work, this book aims to raise the awareness of students, physicists, and engineers in turbulence on the modeling of gravitationally induced turbulent mixing flows as produced, for instance, by Rayleigh-Taylor instabilities. The discussion is centered on the differences between single-fluid and two-fluid approaches, and it is illustrated with a 0D analysis of two specific elementary models in common use. Important deviations are shown to appear on many features, among others the prominence of directed energy, the simultaneous restitution of test cases, the responses to variable acceleration and shocks, and the behavior of various length scales.
Book Synopsis Turbulence Modelling Approaches by : Konstantin Volkov
Download or read book Turbulence Modelling Approaches written by Konstantin Volkov and published by BoD – Books on Demand. This book was released on 2017-07-26 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accurate prediction of turbulent flows remains a challenging task despite considerable work in this area and the acceptance of CFD as a design tool. The quality of the CFD calculations of the flows in engineering applications strongly depends on the proper prediction of turbulence phenomena. Investigations of flow instability, heat transfer, skin friction, secondary flows, flow separation, and reattachment effects demand a reliable modelling and simulation of the turbulence, reliable methods, accurate programming, and robust working practices. The current scientific status of simulation of turbulent flows as well as some advances in computational techniques and practical applications of turbulence research is reviewed and considered in the book.
Book Synopsis Experimental and Numerical Study of Molecular Mixing Dynamics in Rayleigh-Taylor Unstable Flows by : Nicholas J. Mueschke
Download or read book Experimental and Numerical Study of Molecular Mixing Dynamics in Rayleigh-Taylor Unstable Flows written by Nicholas J. Mueschke and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments and simulations were performed to examine the complex processes that occur in Rayleigh-Taylor driven mixing. A water channel facility was used to examine a buoyancy-driven Rayleigh-Taylor mixing layer. Measurements of fluctuating density statistics and the molecular mixing parameter [theta] were made for Pr = 7 (hot/cold water) and Sc ~ 103 (salt/fresh water) cases. For the hot/cold water case, a high-resolution thermocouple was used to measure instantaneous temperature values that were related to the density field via an equation of state. For the Sc ~ 103 case, the degree of molecular mixing was measured by monitoring a diffusion-limited chemical reaction between the two fluid streams. The degree of molecular mixing was quantified by developing a new mathematical relationship between the amount of chemical product formed and the density variance /pr2. Comparisons between the Sc = 7 and Sc ~ 103 cases are used to elucidate the dependence of [theta] on the Schmidt number. To further examine the turbulent mixing processes, a direct numerical simulation (DNS) model of the Sc = 7 water channel experiment was constructed to provide statistics that could not be experimentally measured. To determine the key physical mechanisms that influence the growth of turbulent Rayleigh-Taylor mixing layers, the budgets of the exact mean mass fraction ~m1, turbulent kinetic energy ~E", turbulent kinetic energy dissipation rate ~e", mass fraction variance ~m1"2, and mass fraction variance dissipation rate ~x" equations were examined. The budgets of the unclosed turbulent transport equations were used to quantitatively assess the relative magnitudes of different production, dissipation, transport, and mixing processes. Finally, three-equation (~E"~-e"~-m1"2) and four-equation (~E"~-e"~-m1"2~-X") turbulent mixing models were developed and calibrated to predict the degree of molecular mixing within a Rayleigh-Taylor mixing layer. The DNS data sets were used to assess the validity of and calibrate the turbulent viscosity, gradient-diffusion, and scale-similarity closures a priori. The modeled transport equations were implemented in a one-dimensional numerical simulation code and were shown to accurately reproduce the experimental and DNS results a posteriori. The calibrated model parameters from the Sc = 7 case were used as the starting point for determining the appropriate model constants for the mass fraction variance ~m1"2 transport equation for the Sc ~ 103 case.
Book Synopsis Turbulent Mix Experiments and Simulations by :
Download or read book Turbulent Mix Experiments and Simulations written by and published by . This book was released on 1995 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrodynamic instabilities produce material mixing that can significantly degrade weapons performance. We investigate the Richtmyer-Meshkov (RM) and Rayleigh-Taylor (RT) instabilities in the turbulent regime in two experimental venues. RM experiments are conducted on the Nova laser with strong radiatively driven shocks (Mach> 20) in planar, two fluid targets. Interfacial perturbations are imposed with single sinusoidal modes to test linear theory and with three dimensional (3D) random modes to produce turbulent mix. RT experiments are conducted on a new facility, the Linear Electric Motor (LEM), in which macroscopic fluids are accelerated with arbitrary temporal profiles. This allows detailed diagnosis of the turbulence over a wide range of conditions. The Nova experiments study the high compression regime whereas the LEM experiments are incompressible. The results are compared to hydrodynamic simulations with the arbitrary Lagrangian-Eulerian code (CALE). The goal is to develop and test engineering models of mix.
Book Synopsis Coarse Grained Simulation and Turbulent Mixing by : Fernando F. Grinstein
Download or read book Coarse Grained Simulation and Turbulent Mixing written by Fernando F. Grinstein and published by Cambridge University Press. This book was released on 2016-06-30 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Small-scale turbulent flow dynamics is traditionally viewed as universal and as enslaved to that of larger scales. In coarse grained simulation (CGS), large energy-containing structures are resolved, smaller structures are spatially filtered out, and unresolved subgrid scale (SGS) effects are modeled. Coarse Grained Simulation and Turbulent Mixing reviews our understanding of CGS. Beginning with an introduction to the fundamental theory the discussion then moves to the crucial challenges of predictability. Next, it addresses verification and validation, the primary means of assessing accuracy and reliability of numerical simulation. The final part reports on the progress made in addressing difficult non-equilibrium applications of timely current interest involving variable density turbulent mixing. The book will be of fundamental interest to graduate students, research scientists, and professionals involved in the design and analysis of complex turbulent flows.
Book Synopsis Three Dimensional Simulations of Richtmyer-Meshkov Instabilities in Shock-tube Experiments by :
Download or read book Three Dimensional Simulations of Richtmyer-Meshkov Instabilities in Shock-tube Experiments written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In the large eddy simulation (LES) approach large-scale energy-containing structures are resolved, smaller (presumably) more isotropic structures are filtered out, and unresolved subgrid effects are modeled. Extensive recent work has demonstrated that predictive simulations of turbulent velocity fields are possible based on subgrid scale modeling implicitly provided by a class of high-resolution finite-volume algorithms. This strategy is called implicit LES. The extension of the approach to the substantially more difficult problem of material mixing IS addressed, and progress in representative shock-driven turbulent mixing studies is reported.
