Download or read book Numerical Simulation of the Dynamics and Mixing in a Swirling Flow written by Jean-Claude J. Saghbini and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling and Simulation of Turbulent Mixing and Reaction written by Daniel Livescu and published by Springer Nature. This book was released on 2020-02-19 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights recent research advances in the area of turbulent flows from both industry and academia for applications in the area of Aerospace and Mechanical engineering. Contributions include modeling, simulations and experiments meant for researchers, professionals and students in the area.
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.
Download or read book Swirling Flows and Flames written by Toufik Boushaki and published by BoD – Books on Demand. This book was released on 2019-06-26 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Swirl flows are used in a wide range of industrial applications. In non-reacting cases, examples of applications include vortex amplifiers and reactors, heat exchangers, jet pumps, and cyclone separators. In reacting cases, swirlers are widely used in combustion systems, such as gas turbines, industrial furnaces, boilers, gasoline and diesel engines, and many other practical heating devices. Effects of using swirl on flow and combustion are significant and varied, and concern, for example, aerodynamics, mixing, flame stability, intensity of combustion, and pollutant emissions. The purpose of this book is to present recent research efforts to understand and characterize swirling flows of different types and in different applications. These include gaseous, liquid, and solid fuels in order to enhance combustion systems and their energy efficiency. Swirl flows are very complex and the studies proposed in this project are based on different means, including theoretical calculations, numerical modeling, and experimental measurements.
Download or read book Numerical Techniques for the Simulation of Three Dimensional Swirling Flow written by Daniel Howard and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mixing and Dispersion in Flows Dominated by Rotation and Buoyancy written by Herman J.H. Clercx and published by Springer. This book was released on 2017-10-24 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents a state-of-the-art overview of current developments in the field in a way accessible to attendees coming from a variety of fields. Relevant examples are turbulence research, (environmental) fluid mechanics, lake hydrodynamics and atmospheric physics. Topics discussed range from the fundamentals of rotating and stratified flows, mixing and transport in stratified or rotating turbulence, transport in the atmospheric boundary layer, the dynamics of gravity and turbidity currents eventually with effects of background rotation or stratification, mixing in (stratified) lakes, and the Lagrangian approach in the analysis of transport processes in geophysical and environmental flows. The topics are discussed from fundamental, experimental and numerical points of view. Some contributions cover fundamental aspects including a number of the basic dynamical properties of rotating and or stratified (turbulent) flows, the mathematical description of these flows, some applications in the natural environment, and the Lagrangian statistical analysis of turbulent transport processes and turbulent transport of material particles (including, for example, inertial and finite-size effects). Four papers are dedicated to specific topics such as transport in (stratified) lakes, transport and mixing in the atmospheric boundary layer, mixing in stratified fluids and dynamics of turbidity currents. The book is addressed to doctoral students and postdoctoral researchers, but also to academic and industrial researchers and practicing engineers, with a background in mechanical engineering, applied physics, civil engineering, applied mathematics, meteorology, physical oceanography or physical limnology.
Download or read book Simulation of Turbulent Flows with and without Combustion with Emphasis on the Impact of Coherent Structures on the Turbulent Mixing written by Cunha Galeazzo, Flavio Cesar and published by KIT Scientific Publishing. This book was released on 2016-10-14 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: The analysis of turbulent mixing in complex turbulent flows is a challenging task. The effective mixing of entrained fluids to a molecular level is a vital part of the dynamics of turbulent flows, especially when combustion is involved. The work has shown the limitations of the steady-state simulations and acknowledged the need of applying high-fidelity unsteady methods for the calculation of flows with pronounced unsteadiness promoted by large-scale coherent structures or other sources.
Download or read book Theory and Modeling of Dispersed Multiphase Turbulent Reacting Flows written by Lixing Zhou and published by Butterworth-Heinemann. This book was released on 2018-01-25 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theory and Modeling of Dispersed Multiphase Turbulent Reacting Flows gives a systematic account of the fundamentals of multiphase flows, turbulent flows and combustion theory. It presents the latest advances of models and theories in the field of dispersed multiphase turbulent reacting flow, covering basic equations of multiphase turbulent reacting flows, modeling of turbulent flows, modeling of multiphase turbulent flows, modeling of turbulent combusting flows, and numerical methods for simulation of multiphase turbulent reacting flows, etc. The book is ideal for graduated students, researchers and engineers in many disciplines in power and mechanical engineering. Provides a combination of multiphase fluid dynamics, turbulence theory and combustion theory Covers physical phenomena, numerical modeling theory and methods, and their applications Presents applications in a wide range of engineering facilities, such as utility and industrial furnaces, gas-turbine and rocket engines, internal combustion engines, chemical reactors, and cyclone separators, etc.
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.
Download or read book Swirl Flows written by Ashwani K. Gupta and published by Routledge. This book was released on 1984 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Statistical Theory and Modeling for Turbulent Flows written by P. A. Durbin and published by John Wiley & Sons. This book was released on 2011-06-28 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing a comprehensive grounding in the subject of turbulence, Statistical Theory and Modeling for Turbulent Flows develops both the physical insight and the mathematical framework needed to understand turbulent flow. Its scope enables the reader to become a knowledgeable user of turbulence models; it develops analytical tools for developers of predictive tools. Thoroughly revised and updated, this second edition includes a new fourth section covering DNS (direct numerical simulation), LES (large eddy simulation), DES (detached eddy simulation) and numerical aspects of eddy resolving simulation. In addition to its role as a guide for students, Statistical Theory and Modeling for Turbulent Flows also is a valuable reference for practicing engineers and scientists in computational and experimental fluid dynamics, who would like to broaden their understanding of fundamental issues in turbulence and how they relate to turbulence model implementation. Provides an excellent foundation to the fundamental theoretical concepts in turbulence. Features new and heavily revised material, including an entire new section on eddy resolving simulation. Includes new material on modeling laminar to turbulent transition. Written for students and practitioners in aeronautical and mechanical engineering, applied mathematics and the physical sciences. Accompanied by a website housing solutions to the problems within the book.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book IUTAM Symposium on Dynamics of Slender Vortices written by Egon Krause and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 473 pages. Available in PDF, EPUB and Kindle. Book excerpt: The decision of the General Assembly of the International Union of Theoretical and Applied Mechanics to organize a Symposium on Dynamics of Slender Vortices was greeted with great enthusiasm. The acceptance of the proposal, forwarded by the Deutsches Komitee fiir Mechanik (DEKOMECH) signalized, that there was a need for discussing the topic chosen in the frame the IUTAM Symposia offer. Also the location of the symposium was suitably chosen: It was decided to hold the symposium at the RWTH Aachen, where, years ago, Theodore von Karman had worked on problems related to those to be discussed now anew. It was clear from the beginning of the planning, that the symposium could only be held in the von Karman-Auditorium ofthe Rheinisch-Westfalische Technische Hochschule Aachen, a building named after him. The symposium was jointly organized by the editors of this volume, strongly supported by the local organizing committee. The invitations of the scientific committee brought together scientists actively engaged in research on the dynamics of slender vortices. It was the aim of the committee to have the state of the art summarized and also to have the latest results of specific problems investigated communicated to the participants of the symposium. The topics chosen were asymptotic theories, numerical methods, vor tices in shear layers, interaction of vortices, vortex breakdown, vortex sound, and aircraft and helicopter vortices.
Download or read book Mixing and Fluid Dynamics Under Location Uncertainty written by Valentin Resseguier and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis develops, analyzes and demonstrates several valuable applications of randomized fluid dynamics models referred to as under location uncertainty. The velocity is decomposed between large-scale components and random time-uncorrelated small-scale components. This assumption leads to a modification of the material derivative and hence of every fluid dynamics models. Through the thesis, the mixing induced by deterministic low-resolution flows is also investigated. We first applied that decomposition to reduced order models (ROM). The fluid velocity is expressed on a finite-dimensional basis and its evolution law is projected onto each of these modes. We derive two types of ROMs of Navier-Stokes equations. A deterministic LES-like model is able to stabilize ROMs and to better analyze the influence of the residual velocity on the resolved component. The random one additionally maintains the variability of stable modes and quantifies the model errors. We derive random versions of several geophysical models. We numerically study the transport under location uncertainty through a simplified one. A single realization of our model better retrieves the small-scale tracer structures than a deterministic simulation. Furthermore, a small ensemble of simulations accurately predicts and describes the extreme events, the bifurcations as well as the amplitude and the position of the ensemble errors. Another of our derived simplified model quantifies the frontolysis and the frontogenesis in the upper ocean. This thesis also studied the mixing of tracers generated by smooth fluid flows, after a finite time. We propose a simple model to describe the stretching as well as the spatial and spectral structures of advected tracers. With a toy flow but also with satellite images, we apply our model to locally and globally describe the mixing, specify the advection time and the filter width of the Lagrangian advection method, as well as the turbulent diffusivity in numerical simulations.
Download or read book Unified RANS LES Simulations of Turbulent Swirling Jet Flows written by Celestin P. Zemtsop and published by . This book was released on 2011 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Swirl flows are useful in many engineering and environmental applications. They can be utilized to reduce emissions of pollutants, to improve ignition stability, and to stabilize a flame for clean combustion. The majority of swirl flows include both wall-bounded regions and free shear flow regions. Experimental research cannot provide all the information needed for the study of these flows. Numerical simulations of swirl flows provide more insights into the structure of the swirl flows. The direct numerical simulation (DNS) method is an accurate and reliable tool for flow simulations but computationally expensive. Reynolds-averaged Navier-Stokes (RANS) methods are computationally less expensive for the simulation of wall-bounded and free shear flows, but they turn out to be not well appropriate for turbulent swirling jet simulations. Large-eddy simulation (LES) is an appropriate modeling approach for turbulent swirl flow simulations, but the calculation of the free swirling jet using LES needs fluctuating inlet velocity conditions. The generation of such fluctuating velocity fields could be done by performing a LES of the nozzle flow. Unfortunately, the computational costs of such LES are comparable to those of DNS. A need thus arises to apply a hybrid RANS/LES method that combines two main advantages, the capability of LES methods in capturing instantaneous flow structures and the low computational costs of RANS methods. In this study, the performance of two hybrid approaches, a segregated RANS/LES method, and a unified RANS/LES method, is investigated regarding the simulation of turbulent swirling jet flows. The segregated model combines a RANS model in the nozzle region and a LES model in the jet region, whereas the unified model combines a RANS model in near-wall regions with a LES model away from the wall. This study provides evidence that the unified turbulence model is a better tool to predict swirl flows and, more importantly, a better tool to calculate the vortex breakdown. The accuracy of the numerical predictions is confirmed by comparing available experimental data for non-swirling and swirling jet flows with computational results. The validated model is used to study the mechanism of swirl effects, vortex breakdown, and scalar mixing.
Download or read book Proceedings of The 5th International Conference on Advances in Civil and Ecological Engineering Research written by Chih-Huang Weng and published by Springer Nature. This book was released on 2023-10-01 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents select proceedings of the 5th International Conference on Advances in Civil and Ecological Engineering Research (ACEER 2023). The book covers a wide range of topics, including construction engineering and management hydraulic and hydrologic engineering, air quality and atmospheric pollution, ecological risk assessment and management, restoration and protection of environment, water pollution and treatment, and water recourses engineering. This book also covers state-of-the-art technologies in building sustainable city, resilient buildings, and sustainable issues in relating to civil engineering. It will be useful for researchers and engineers working in the field of civil and ecological engineering.
Download or read book Multiphase reacting flows modelling and simulation written by Daniele L. Marchisio and published by Springer Science & Business Media. This book was released on 2007-10-16 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the most widely applicable modeling approaches. Chapters are organized in six groups covering from fundamentals to relevant applications. The book covers particle-based methods and also discusses Eulerian-Eulerian and Eulerian-Lagrangian techniques based on finite-volume schemes. Moreover, the possibility of modeling the poly-dispersity of the secondary phases in Eulerian-Eulerian schemes by solving the population balance equation is discussed.
