Download or read book Dynamics of Non Spherical Particles in Turbulence written by Luis Blay Esteban and published by Springer. This book was released on 2019-08-13 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book studies the dynamics of 2D objects moving through turbulent fluids. It examines the decay of turbulence over extended time scales, and compares the dynamics of non-spherical particles moving through still and turbulent fluids. The book begins with an introduction to the project, its aims, and its relevance for industrial applications. It then discusses the movement of planar particles in quiescent fluid, and presents the numerous methodologies used to measure it. The book also presents a detailed analysis of the falling style of irregular particles, which makes it possible to estimate particle trajectory and wake morphology based on frontal geometry. In turn, the book provides the results of an analysis of physically constrained decaying turbulence in a laboratory setting. These results suggest that large-scale cut-off in numerical simulations can result in severe bias in the computed turbulent kinetic energy for long waiting times. Combining the main text with a wealth of figures and sketches throughout, the book offers an accessible guide for all engineering students with a basic grasp of fluid mechanics, while the key findings will also be of interest to senior researchers.

Download or read book The Dynamics of Non Spherical Particles written by Isaiah Gallily and published by . This book was released on 1977 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper the aerodynamic translational mobility of nonsphericals was experimentally determined for Knudsen numbers of up to 0.2. The particles were glass cylinders, which represent asbestos fibers and ice needles, and cubes, which represent the primary constituents of metal oxide aggregates. The method of determination and the apparatus used were based on a stereophotography of the trajectories of the particles in still air and a photogrammetric measurement of the (three) dimensions of the particles in a scanning electron microscope. The results for cylinders, compared with continuous fluid theoretical values of the coefficients, show a reasonable correspondence with expectation which even improved when the blunt edge effect of the particles was taken into consideration. However, in the case of cylinders having diameters above 1 micrometers, the experimentally determined coefficients were higher by about 50% than the continuous fluid calculated ones, whereas in the case of cylinders of diameters less than 0.5 micrometers, the determined coefficients were smaller than the calculated values. The resistance coefficients of cubes showed similar tendencies. The deposition of cylindrical particles in still air was studied in a specially constructed sedimentation cell; in this cell, a method for the size distribution analysis of these particles was tried.

Download or read book The Dynamics of Non Spherical Particles Part II Mobility in Non Orienting Fields written by Isaiah Gallily and published by . This book was released on 1975 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents the stochastic nature of the mobility of aerosol particles in non-orienting fields of force. A dynamic model for the interaction between particles' translation and Brownian rotation was assumed and a Monte Carlo method applied to compute the distribution of particles' (verticle) trajectories. The distribution was calculated for several particle shapes, various geometric dimensions, various total times of motion, and various initial orientations. From the calculations it was seen that the aerodynamic diameter is actually a statistical parameter, which should be taken into account. On the experimental side, the principal translational coefficients of cylindrical glass fibers was determined with the aid of a special apparatus and technique. Fibers' dimensions were found according to a previously developed photogrammetric method, employing a scanning electron microscope.

Download or read book The Dynamics of Non spherical Particles 1 Controlled Generation of Non spherical Aerosols and Methods for Their Size Concentration and Electric Charge Measurement written by Isaiah Gallily and published by . This book was released on 1974 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The typical features of the motion of a nonspherical aerosol particle are discussed, an overall aim concerning its behavior in systems of importance for human environment is stated and a preliminary objective of studying methods for generation, size measurement, determination of concentration and assessment of electric charge is set. Previous investigations in these lines are reviewed. Starting with model shapes, there were produced by solution spray-drying almost perfect cubes or parallelpipeds and, by suspension gas atomization, cylindrical particles of glass fibers. Dispersion of powders by air turbulence was treated theoretically and a computational investigation of the adhesional energy between two parallelpipeds at various mutual orientations begun. The size parameters of the produced particles were determined. A way of assessing the electric charge of a nonspherical particle is analyzed in view of the specificity of its motion and the relation to the principal translational resistances brought out. The effect of Brownian rotation on the translation of an aerosol particle was discussed. An apparatus for the determination of the principal resistances of a nonspherical particle at various Knudsen numbers has been constructed and a mathematical procedure for the elucidation of results developed.

Download or read book Orientational Dynamics of Small Non spherical Particles in Fluid Flows written by and published by . This book was released on 2013 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rheology of Non spherical Particle Suspensions written by Francisco Chinesta and published by Elsevier. This book was released on 2015-10-06 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a review of the current understanding of the behavior of non-spherical particle suspensions providing experimental results, rheological models and numerical modeling. In recent years, new models have been developed for suspension rheology and as a result applications for nanocomposites have increased. The authors tackle issues within experimental, model and numerical simulations of the behavior of particle suspensions. Applications of non-spherical particle suspension rheology are widespread and can be found in organic matrix composites, nanocomposites, biocomposites, fiber-filled fresh concrete flow, blood and biologic fluids. Understand how to model and predict the final microstructure and properties of particle suspensions Explores nano, micro, meso and macro scales Rheology, thermomechanical and electromagnetic physics are discussed

Download or read book Understanding the Discrete Element Method written by Hans-Georg Matuttis and published by John Wiley & Sons. This book was released on 2014-05-12 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gives readers a more thorough understanding of DEM and equips researchers for independent work and an ability to judge methods related to simulation of polygonal particles Introduces DEM from the fundamental concepts (theoretical mechanics and solidstate physics), with 2D and 3D simulation methods for polygonal particles Provides the fundamentals of coding discrete element method (DEM) requiring little advance knowledge of granular matter or numerical simulation Highlights the numerical tricks and pitfalls that are usually only realized after years of experience, with relevant simple experiments as applications Presents a logical approach starting withthe mechanical and physical bases,followed by a description of the techniques and finally their applications Written by a key author presenting ideas on how to model the dynamics of angular particles using polygons and polyhedral Accompanying website includes MATLAB-Programs providing the simulation code for two-dimensional polygons Recommended for researchers and graduate students who deal with particle models in areas such as fluid dynamics, multi-body engineering, finite-element methods, the geosciences, and multi-scale physics.

Download or read book Microscale Dynamics in Suspensions of Non spherical Particles written by Amit Kumar and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical simulations were performed to investigate the microscale dynamics in suspensions of spherical and non-spherical particles. Two new algorithms were developed to enable studies with accurate hydrodynamics. The first algorithm was a high accuracy Stokesian Dynamics technique (SD) extended to a generic non-spherical particle shape. The many body interactions were computed using a novel scheme employing one body singularity solutions. Near field lubrication interactions employed standard asymptotic solutions for nearly touching convex particles. The second algorithm was a reduced precision near-field lubrication based method called Fast Lubrication Dynamics (FLD). In addition to the near field interactions, we introduced a novel isotropic resistance in FLD to match the mean particle mobility from the more detailed SD. The resulting FLD algorithm was shown to give results comparable to that from the detailed SD, while requiring only a fraction of the latter's computational expense. In a first series of studies using the SD technique, we computed the transport properties in equilibrium suspensions of spheres and dicolloids. The latter particle shape was modeled as two intersecting spheres of varying radii and center to center separations. It was found that the infinite frequency viscosity as well as the short-time translational self-diffusivity are non-monotonic function of aspect ratio at any given non-dilute volume fraction with the minima in viscosity and the maxima in self-diffusivity around an aspect of 1.5. In contrast, the short-time rotational self-diffusivity was found to be a monotonically decreasing function of the aspect ratio at any given volume fraction. In a second series of studies using the SD technique we investigated the microstructure, orientation, and rheology in suspensions of spheres and dicolloids over a wide range of volume fractions $0 leq phi leq 0.55$. The particles had a very short range repulsive interparticle interaction. The microstructure in suspensions of all particle shapes was found to be disordered for volume fractions $phi leq 0.5$, while a string like ordering was observed in suspensions of spheres and other particles with small degree of anisotropy at $phi=0.55$. Both the first and the second normal stress differences were negative for volume fractions up to $phi=0.5$, but some were positive at the highest volume fraction studied here ($phi=0.55$). The orientation behavior was found to be a function of both the fore-aft symmetry and the degree of anisotropy. For particles with fore-aft symmetry, in comparison to infinite dilution, a shift to higher orbit constants (increased alignment in the flow-gradient plane) was observed at low volume fractions. On the other hand, the particle lacking fore-aft symmetry showed virtually no change in its orientation distribution at low volume fractions. At higher volume fractions ($phi geq 0.2$), in comparison to the dilute suspensions, a shift towards lower orbit constants (increased alignment with the vorticity axis) was observed for all particle shapes. The degree of this alignment was found to increase with volume fraction for particles with small degree of anisotropy, while it was found to plateau at relatively low volume fractions in suspensions of particles with the largest degree of anisotropy. The observed orientation behavior was explained using a novel analysis technique based on the coupling of particle's angular velocity and hydrodynamic stresslet through the mobility tensor. Next, we investigated microstructure and orientation in Brownian suspensions of spheres and dicolloids using the FLD algorithm. Results are reported for two different volume fractions, $phi=42%$ and $phi=55%$. The 42% sample had a long range repulsive electrostatic interaction, while the 55% sample had hard-sphere type interaction. Particles with small degree of anisotropy showed microstructural transitions similar to that of spheres. In contrast, particles with relatively larger degree of anisotropy showed a significantly different microstructural behavior. At low shear rates, irrespective of the degree of anisotropy, an orientationally disordered state was observed. Upon further increase in the rate of shear, an increase in flow alignment is obtained, with the maximum flow alignment typically observed between $Pe=1$ and $Pe=20$ depending on the particle shape. With a further increase in the rate of shear, an increase in vorticity alignment is seen for all particle shapes. The degree of anisotropy and volume fraction was found to have a significant impact on the extent of increase in the flow or the vorticity alignment. Using FLD simulations we next investigated the phase behavior and rheology in charged colloidal suspensions at a volume fraction of $phi=0.33$. It was shown that for a given screening length of the repulsive interaction, there existed a range of surface potentials for which both the ordered and disordered metastable states exist. This range was found to have a strong dependence on shear rate and was found to have a maximum width around $Pe = 0.5$, where $Pe = dot{gamma}a^2/D_0$. The presence of both the ordered and disordered metastable states allowed us to simultaneously characterize both the branches of viscosity as a function of shear rate. It was observed that the disordered branch can have a lower viscosity than the ordered branch at low shear rates ($Pe

Download or read book Scattering from Model Nonspherical Particles written by Ferdinando Borghese and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the first coherent account of a well-known approach to the problem of light scattering by small anisotropic particles. In this extended second edition the authors have encompassed all the new topics arising from their recent studies of cosmic dust grains. Thus many chapters were deeply revised and new chapters were added. The book addresses a wide spectrum of applications.

Download or read book The Dynamics of Nonspherical Particles written by Isaiah Gallily and published by . This book was released on 1974 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Collective Dynamics of Particles written by Cristian Marchioli and published by Springer. This book was released on 2017-02-21 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book surveys the state-of-the-art methods that are currently available to model and simulate the presence of rigid particles in a fluid flow. For particles that are very small relative to the characteristic flow scales and move without interaction with other particles, effective equations of motion for particle tracking are formulated and applied (e.g. in gas-solid flows). For larger particles, for particles in liquid-solid flows and for particles that interact with each other or possibly modify the overall flow detailed model are presented. Special attention is given to the description of the approximate force coupling method (FCM) as a more general treatment for small particles, and derivations in the context of low Reynolds numbers for the particle motion as well as application at finite Reynolds numbers are provided. Other topics discussed in the book are the relation to higher resolution immersed boundary methods, possible extensions to non-spherical particles and examples of applications of such methods to dispersed multiphase flows.

Download or read book Dynamics and Coagulation of Non Spherical Particles Settling in Shear Flows written by Hod Wirzberger and published by . This book was released on 2004 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamics of Single Non spherical Ellipsoidal Particles in a Turbulent Channel Flow written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Behavior of Large Particles Falling in Quiescent Liquids written by G. E. Stringham and published by . This book was released on 1969 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Additive Manufacturing of Metals written by John O. Milewski and published by Springer. This book was released on 2017-06-28 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: This engaging volume presents the exciting new technology of additive manufacturing (AM) of metal objects for a broad audience of academic and industry researchers, manufacturing professionals, undergraduate and graduate students, hobbyists, and artists. Innovative applications ranging from rocket nozzles to custom jewelry to medical implants illustrate a new world of freedom in design and fabrication, creating objects otherwise not possible by conventional means. The author describes the various methods and advanced metals used to create high value components, enabling readers to choose which process is best for them. Of particular interest is how harnessing the power of lasers, electron beams, and electric arcs, as directed by advanced computer models, robots, and 3D printing systems, can create otherwise unattainable objects. A timeline depicting the evolution of metalworking, accelerated by the computer and information age, ties AM metal technology to the rapid evolution of global technology trends. Charts, diagrams, and illustrations complement the text to describe the diverse set of technologies brought together in the AM processing of metal. Extensive listing of terms, definitions, and acronyms provides the reader with a quick reference guide to the language of AM metal processing. The book directs the reader to a wealth of internet sites providing further reading and resources, such as vendors and service providers, to jump start those interested in taking the first steps to establishing AM metal capability on whatever scale. The appendix provides hands-on example exercises for those ready to engage in experiential self-directed learning.

Download or read book Multiphase Flow and Fluidization written by Dimitri Gidaspow and published by Elsevier. This book was released on 2012-12-02 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Useful as a reference for engineers in industry and as an advanced level text for graduate engineering students, Multiphase Flow and Fluidization takes the reader beyond the theoretical to demonstrate how multiphase flow equations can be used to provide applied, practical, predictive solutions to industrial fluidization problems. Written to help advance progress in the emerging science of multiphase flow, this book begins with the development of the conservation laws and moves on through kinetic theory, clarifying many physical concepts (such as particulate viscosity and solids pressure) and introducing the new dependent variable--the volume fraction of the dispersed phase. Exercises at the end of each chapterare provided for further study and lead into applications not covered in the text itself. Treats fluidization as a branch of transport phenomena Demonstrates how to do transient, multidimensional simulation of multiphase processes The first book to apply kinetic theory to flow of particulates Is the only book to discuss numerical stability of multiphase equations and whether or not such equations are well-posed Explains the origin of bubbles and the concept of critical granular flow Presents clearly written exercises at the end of each chapter to facilitate understanding and further study

Download or read book Non spherical Particle Dynamics Analysis with Applications to Inhaled Aerosol Transport and Deposition in Human Upper Airway Models written by Yu Feng and published by . This book was released on 2013 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: