Download or read book Flow Visualization and Modeling of Liquid Crystalline Polymers written by Mark Naoshi Kawaguchi and published by . This book was released on 1998 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multi scale Modeling of Liquid Crystalline Polymers written by Robert Kehalani Sentinella and published by ProQuest. This book was released on 2008 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid Crystalline Polymers have a wide variety of applications. They are not only interesting to the industrial world, but to the academic world as well. To take full advantage of these interesting materials, it is necessary to develop numerical algorithms that predict their behavior when subjected to processing flows. In the current work, an algorithm was developed that directly solves the full Doi-Marrucci-Greco (DMG) model for a 2D flow domain when subjected to simple shear flow. This algorithm is referred to as the direct solver. Due to the extremely high computational cost of implementing this direct solver, a Multi-Resolution based methodology was designed and proves to be a viable technique in reducing this cost. It also displays promise as a tool that could be applied to different complex fluids problems and perhaps beyond.

Download or read book Rheology and Processing of Liquid Crystal Polymers written by Domenico Acierno and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 331 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystal polymers (LCPs) have many strange properties that may be utilized to advantage in the processing of products made from them and their blends with isotropic polymers. This volume (volume 2 in the series Polymer Liquid Crystals) deals with their strange flow behaviour and the models put forward to explain the phenomena that occur in such polymers and their blends. It has been known for some time that small ad ditions of a thermotropic LCP to isotropic polymers not only gives an improvement in the strength and stiffness of the blend but improves the processability of the blend over that of the isotropic polymer. In the case of lyotropic LCPs, it is possible to create a molecular composite in which the reinforcement of an isotropic polymer is achieved at a molecular level by the addition of the LCP in a common solvent. If the phenomena can be fully understood both the reinforcement and an increase in the proces sability of isotropic polymers could be optimized. This book is intended to illustrate the current theories associated with the flow of LCPs and their blends in the hope that such an optimization will be achieved by future research. Chapter 1 introduces the subject of LCPs and describes the ter minology used; Chapter 2 then discusses the more complex phenomena associated with these materials. In Chapter 3, the way in which these phe nomena may be modelled using hamiltonians is fully covered.

Download or read book Fluid Mechanics and Rheology of Fluid Fiber Flows Fundamental Science and Technological Applications written by Qi Wang and published by . This book was released on 1999 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research activities are focused on modeling of polymeric liquid crystal (LCP) flows. We first summarizes our comprehensive studies on the shear and elongational flow with an imposed velocity field. This includes a complete characterization of the orientational equilibrium and their bifurcation behavior as well as the detailed study on the orientation dynamics with respect to both types of flows. In particular, biaxial patterns and their dynamics are treated carefully. We then report on the work on the modeling of fiber spinning processes of thermotropic liquid crystal polymers, where new models along with an extensive study for fiber flows of thermotropic liquid crystals are presented. The study on the influence of microstructure on the capillary instability of liquid crystal jets follows. Finally, we report on some long wave stability analysis for ideal liquid jets of LCPs and the progress on some ongoing projects.

Download or read book Flow Visualization VI written by Yoshimichi Tanida and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 904 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decade, flow visualization has advanced in step with the progress in laser and computer technologies. The scope of the International Symposium on Flow Visualiza- tion will be broader than ever, covering the range of infor- mation generally thought of as nonvisual and reflecting the inclusion of computer - aided methodologies. The Sixth In- ternational Symposium on Flow Visualization aims to attract the participation of experts and users of flow viualizing techniques on furthering an advanced philosophy for the de- velopment of the methods and their applications.

Download or read book Micro macro Simulations of Liquid Crystalline Polymers written by Brandon Masao Kerr and published by . This book was released on 2012 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a numerical method to evolve the flow dynamics of a model for nematic liquid crystalline polymers (LCPs) in a recirculating cavity flow, coupling the Doi model for the microstructure of the fluid with the incompressible Navier-Stokes equations of motion. In particular, we model the flow dynamics of a LCP confined to a square channel with a lid moving at a constant speed under the simplifying assumption that there are no spatial gradients in the direction of the channel's length, i.e., the only relevant flow dynamics occur in a 2-dimensional, square flow domain. Flow patterns typical of this system include rotation near the center of the domain, extensional flow near the boundaries, and counter-rotating vortices in the corners. We use the spherical harmonics transform to develop a Fokker-Planck solver to evolve the microstructure and utilize the Projection Method to evolve the macroscopic flow. At increasing Deborah numbers, the model captures the formation of +1/2 and +1 disclinations in the microstructure and suggests four regimes of dynamics of the microstructure: tumbling between two anisotropic layers, stabilization of the tumbling with formation of a +1/2 disclination, destabilization with the formation of a second +1/2 disclination, and re-stabilization. This progression of the dynamics demonstrates a wagging-to-flow-aligning transition at De=3 rather than at De=5, as observed experimentally by Larson and Mead [Liquid Crystals, 15 (1993), pp. 151-169]. Furthermore, instead of simply a tumbling-to-wagging transition at De=2, this model predicts a transition from tumbling to equilibrating at De=1 and then to wagging at De=2.

Download or read book Computer Simulations of Liquid Crystals and Polymers written by Paolo Pasini and published by Springer Science & Business Media. This book was released on 2005-02-15 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystals, polymers and polymer liquid crystals are soft condensed matter systems of major technological and scientific interest. An understanding of the macroscopic properties of these complex systems and of their many and interesting peculiarities at the molecular level can nowadays only be attained using computer simulations and statistical mechanical theories. Both in the Liquid Crystal and Polymer fields a considerable amount of simulation work has been done in the last few years with various classes of models at different special resolutions, ranging from atomistic to molecular and coarse-grained lattice models. Each of the two fields has developed its own set of tools and specialized procedures and the book aims to provide a state of the art review of the computer simulation studies of polymers and liquid crystals. This is of great importance in view of a potential cross-fertilization between these connected areas which is particularly apparent for a number of experimental systems like, e.g. polymer liquid crystals and anisotropic gels where the different fields necessarily merge. An effort has been made to assess the possibilities of a coherent description of the themes that have developed independently, and to compare and extend the theoretical and computational techniques put forward in the different areas.

Download or read book Handbook of Liquid Crystals 8 Volume Set written by John W. Goodby and published by John Wiley & Sons. This book was released on 2014-04-14 with total page 5240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Much more than a slight revision, this second edition of the successful "Handbook of Liquid Crystals" is completely restructured and streamlined, with updated as well as completely new topics, 100% more content and a new team of editors and authors. As such, it fills the gap for a definitive, single source reference for all those working in the field of organized fluids and will set the standard for the next decade. The Handbook's new structure facilitates navigation and combines the presentation of the content by topic and by liquid-crystal type: A fundamentals volume sets the stage for an understanding of the liquid crystal state of matter, while individual volumes cover the main types and forms, with a final volume bringing together the diverse liquid crystal phases through their applications. This unrivaled, all-embracing coverage represents the undiluted knowledge on liquid crystals, making the Handbook a must-have wherever liquid crystals are investigated, produced or used, and in institutions where their science and technology is taught. Also available electronically on Wiley Online Library, www.wileyonlinelibrary.com/ref/holc Volume 1: Fundamentals of Liquid Crystals Volume 2: Physical Properties and Phase Behavior of Liquid Crystals Volume 3: Nematic and Chiral Nematic Liquid Crystals Volume 4: Smectic and Columnar Liquid Crystals Volume 5: Non-Conventional Liquid Crystals Volume 6: Nanostructured and Amphiphilic Liquid Crystals Volume 7: Supermolecular and Polymeric Liquid Crystals Volume 8: Applications of Liquid Crystals

Download or read book Molecular Simulation of Liquid Crystal Polymer Flow written by Radha Nayak and published by . This book was released on 1998 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pressure Driven Flows of a Model Liquid Crystalline Polymer written by J. Feng and published by . This book was released on 1998 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Liquid Crystalline and Mesomorphic Polymers written by Valery P. Shibaev and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Among the various new directions in modern polymer science, the design and investigation of liquid crystal (LC) polymers have been the ones growing most actively and fruitfully. In spite of that, the possible formation of an anisotropic LC phase was only demonstrated theoretically for the first time in the 1950s by Onsager [1] and Flory [2], and then experimentally verified in the studies with polypeptides solutions. In essence, the studies of these LC lyotropic systems did not deviate from the theme of purely academic interest. It was at the beginning of the 1970s that the experimental "explosion" occurred, when aromatic polyamides were synthesized and their ability to form LC solutions in certain very aggressive solvents was discovered. The search for practical applications of such LC systems was crowned with the successful creation of the new generation of ultrastrong high-modulus ther mostable fibers, such as the Kevlar, due to the high degree of order of the macromolecules in the anisotropic LC state. In fact, these investigations coincided with the swift emergence on the practical "scene" of thermotropic low-molar-mass liquid crystals, with the use of these materials in microelectronics and electro optics (figures and let ters indicators, displays in personal computers, and flat TV, etc.). Polymer scientists also began to develop methods of synthesizing thermotropic LC polymers by incorporating mesogenic fragments in the main (main-chain LC polymers) or side branchings of the macromolecules (side-chain or comb shaped polymers).

Download or read book Polymeric Liquid Crystals written by Alexandre Blumstein and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 455 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book originated in the Proceedings of the Second Symposium on Polymeric Liquid Crystals held by the Division of Polymer Chemistry in the framework of the 1983 Fall Meeting of the American Chemical Society. At the First Symposium in 1977, the literature in this field could be encompassed in a single volume. To day, that is no longer possible. The field of Polymeric Liquid Crystals grew, and continues to grow, at a very rapid pace. At present, we know of every major mesophase in its polymeric form and of polymeric glasses, elastomers and fluids in their liquid crystalline form. Every year, new polymeric mesophases are being discovered. The aim of this book is to go beyond a compilation of papers presented at the 1983 ACS Fall Meeting. It is conceived as a learning tool for the benefit of the sci entist interested in Polymeric Liquid Crystals. The book is divided into three sections. The first section contains articles discussing synthetic, physico chemical, structural and rheological aspects of Polymeric Liquid Crystals in their generality. A chapter on methods currently used in this field is also included. There are also chapters on theoretical and classification aspects of PLCs. These self-contained tutorial chapters provide an introduction to this field as well as to the specific papers given in the book. They provide an exhaustive cover age of literature on the subject from its inception to the present.

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1977 with total page 918 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multiscale Simulation of Viscoelastic Flows written by Jason Ka-Chun Suen and published by . This book was released on 2003 with total page 726 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) Simulations of the original Doi model with the Maier-Saupe potential in a pressure-driven channel flow by Nayak showed disclination formation due to the shear-rate-dependent frequencies of the tumbling/wagging states of the Doi model in a shear or mixed shear flow. The lack of an instrinsic length scale in the model leads to an infinitesimal structure refinement that eventually causes numerical instabilities. In this thesis, the effect of concentration variation is incorporated to develop a modified Doi model for introducing an intrinsic length scale through translational diffusion. This changes the mathematical characteristics of the spatial variation of the underlying diffusion equation from that of a hyperbolic equation to that of an elliptic equation. The resulting elliptic diffusion equation is then solved by using a local discontinuous Galerkin method, where an auxillary variable is introduced to rewrite the elliptic diffusion equation into a pair of formal, hyperbolic equations, which in turn is solved by the standard discontinuous Galerkin method. Unlike the original Doi model, a steady state is reached for a variety of De. Although there is structure variation across the channel width, the director profiles point uniformly along the flow direction. The lack of disclination formation may be rectified by introducing Frank elasticity into the modified Doi model ...

Download or read book Structure Development During Converging Flow of a Liquid Crystal Dispersed Two Phase Fluid written by P. J. Yanisko and published by . This book was released on 1989 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flow dynamics of liquid crystal (LC)-dispersed two phase fluids were studied in order to determine the relationships between the deformation of the dispersed phase (D), the weber number (We) and the viscosity ratio of the two phases (k). A flow visualization apparatus consisting of a glass capillary with aconical converging entrance and a video system was constructed and used to measure droplet deformation in the entrance region (extensional flow) and in the capillary (shear flow). The systems studied included p-ethoxybenzyline-p-butylanine (EBBA) dispersed in three Newtonian fluids (50, 80, and 100% glycerin (aq)) and three viscoelastic, non Newtonian fluids (0.35. 1.0, and 1.5% polyacrylamide (aq)). The data were compared with the theoretical predictions for non-LC containing two phase fluids by Reijden-Stolk and Sara. D increased with increasing We and it appeared that LC droplets may experience more deformation than isotropic fluid dispersions for comparable values of We and K. Keywords: Liquid crystalline polymer. (MJM).

Download or read book Dynamics of a Model for Nematic Liquid Crystalline Polymers in Planar Shear Flow written by David Harley Klein and published by ProQuest. This book was released on 2007 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystalline polymers (LCPs) have found a multitude of applications in the form of fibers, and applications that take advantage of the low thermal expansion coefficient and relatively low viscosity of LCPs such as small-scale precision molded parts. In spite of these successes, however, there are other potentially more important applications that have not been realized, among which the greatest loss is the inability to produce high-strength, lightweight engineering materials with mechanical properties that derive from the spontaneous ordering LCPs display in the liquid state. The difficulty lies in the fact that, although the spinning process used to produce fibers enhances this tendency for ordering, other forms of polymer processing, such as injection molding, involve either shear flows or combinations of shear and extensional flows. For LCPs that tumble in shear flows--which include all lyotropic and, apparently, many commercially interesting thermotropic LCPs--these flows seriously degrade or even destroy the orientational order.