Download or read book THE MECHANICS AND STABILITY OF LIQUID JETS AND FILMS JET ATOMIZATION written by KEVIN RICHARD JOHN ELLWOOD and published by . This book was released on 1991 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: The underlying objective of this thesis is to study the process of coating by jet atomization, whose mechanism is divided into the mechanics and stability of liquid jets and the dynamics of thin films.

Download or read book Free Liquid Jets and Films written by Alexander L. Yarin and published by Chapman & Hall/CRC. This book was released on 1993 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: An examination of the hydrodynamics of free liquid jets and the films of viscous and rheologically complex (in particular, polymeric) liquids. Offering a unique and comprehensive coverage of an important topic, this volume will be invaluable for all those involved in applied mathematics, computational fluid mechanics, hydrodynamics, rheology, applied physics, as well as chemical and mechanical engineering.

Download or read book The Mechanics of Liquid Jets written by James N. Anno and published by Great Source Education Group. This book was released on 1977 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optimized Amplification of Interface Distortion on Liquid Jets written by Hanul Hwang and published by . This book was released on 2022 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A fragmentation process of the liquid jet begins with the amplification of small disturbances. Understanding the evolution of the initial perturbation is critical in controlling the quality of the atomization outcomes, such as the droplet size distribution and the evaporation rate of the liquid, as these are directly related to the performance of a variety of atomization applications. In this study, we identify a novel mechanism for the effective amplification of the initial perturbation on liquid jets. This mechanism is independent of the exponential instability of the flow and can intensify small perturbations to the material interface by several orders of magnitude. Depending on its operating conditions, the liquid jet can amplify interfacial disturbances at a faster pace than can modal mechanisms such as the Kelvin--Helmholtz (K--H) instability. This study is based on a spatial linear stability theory in a two-fluid formulation that accounts for both viscosity and surface tension effects. The identified mechanism is verified using nonlinear simulations. In simulations, we observe nonlinear effects that create small-scale structures, a result not predicted in linear theory. As a measure of effective atomization, the small-scale structures are quantified by computing the surface area of the liquid jet. A study comparing the surface area between the liquid jet perturbed by the identified mechanism and the random inlet perturbation results higher surface area, which indicates that the identified mechanism drives more severe corrugation on the material interface leading to an effective atomization. A systematic framework for stability analysis of two-phase flows is constructed. The base flow of liquid jets is assumed to be streamwise invariant, stationary in time, axisymmetric, and laminar. Because of these assumptions, the base flow remains as the only function of radial direction. The ansatzes for the disturbance on a liquid jet are exponential functions in corresponding homogeneous directions. For an inhomogeneous direction, i.e., radial direction, disturbances are discretized using the Chebyshev spectral method. With linearized Navier-Stokes equations, the base flow, kinematic/dynamic interface conditions, and boundary conditions, analyzing the stability of liquid jets boils down to a well-posed eigenvalue problem. The eigenvalue problem is solved in the spatial framework where the input is a real perturbation frequency, and the outcomes are complex wavenumbers with corresponding eigenfunctions. A computationally cost-effective method is proposed to evaluate of eigenmode propagation direction. Unlike the temporal eigenvalue problem, solving the spatial eigenvalue problem adds more complexity in that the propagation direction of eigenmodes must be identified. Here, we solve the adjoint eigenvalue problem and invoke bi-orthogonality of the eigenfunctions to evaluate the group velocity of each eigenmode. With this group velocity evaluation metric, downstream propagating modes are identified. The effect of vorticity layer thickness on the downstream propagating unstable mode of liquid jets is explored. In addition, the identification of eigenmodes is illustrated using energy budgets. In contrast to classical modal growth analysis, a new pathway leading to an effective surface distortion of liquid jets is studied in detail. Analysis of the new mechanism is cast as an optimization problem that maximizes surface tension energy gain from the inlet perturbation distribution at the nozzle and discounts the trivial redistribution of perturbation kinetic energy. The identified mechanism is related to the Orr mechanism, and it amplifies distortions to the material interface via a reorientation of perturbations by the mean shear. Analyses of the linearized energy budgets show that energy is extracted from the mean shear by the production term of the streamwise perturbation velocity component and subsequently is transferred to the radial perturbation velocity component, where it is absorbed by the surface-tension potential of the interface. The gain in surface tension energy attributable to the mechanism is shown to scale linearly with the Reynolds number. A critical Weber number is identified as a lower bound beyond which the mechanism becomes active, and a power-law relation to the Reynolds number is established. The realizability of the identified mechanism is verified using nonlinear simulations. Numerical simulations of the optimized jets are conducted with a weakly compressible multiphase solver on an unstructured grid with algebraic VoF as an interface-tracking algorithm. We demonstrate the multiphase Orr mechanism as a realizable process for liquid jet atomization with various flow conditions. The comparison study of liquid jet surface area between the randomly disturbed jet and the optimized jet demonstrates the formation of the small-scale structures, and hence the ligaments, occurring within a relatively short downstream distance in the latter case.

Download or read book Fundamental Mechanism of Liquid Jet Atomization written by Daejoon Kang and published by . This book was released on 1988 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Breakup of Liquid Sheets and Jets written by S. P. Lin and published by Cambridge University Press. This book was released on 2003-08-21 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book, first published in 2003, is an exposition of what we knew about the physics underlying the onset of instability in liquid sheets and jets. Wave motion and breakup phenomena subsequent to the onset of instability are carefully explained. Physical concepts are established through rigorous mathematics, accurate numerical analyses and comparison of theory with experiment. Exercises are provided for students, and these help familiarize the reader with the required mathematical tools. This book further provides a rational basis for designing equipment and processes involving the phenomena of sheet and jet breakup. Researchers interested in transition to turbulence, hydrodynamic stability or combustion will find this book a highly useful resource, whether their background lies in engineering, physics, chemistry, biology, medicine or applied mathematics.

Download or read book Liquid Atomization written by L.P. Bayvel and published by Routledge. This book was released on 2019-01-22 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering the basics of liquid atomization, this book familiarizes readers with the physical processes of liquid atomization, the main types of atomizers and their design, measurements of spray characteristics, experimental investigations of atomizers, and application of atomizers. It demonstrates how to calculate and design atomizers and how to mea

Download or read book Handbook of Atomization and Sprays written by Nasser Ashgriz and published by Springer Science & Business Media. This book was released on 2011-02-18 with total page 922 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atomization and sprays are used in a wide range of industries: mechanical, chemical, aerospace, and civil engineering; material science and metallurgy; food; pharmaceutical, forestry, environmental protection; medicine; agriculture; meteorology and others. Some specific applications are spray combustion in furnaces, gas turbines and rockets, spray drying and cooling, air conditioning, powdered metallurgy, spray painting and coating, inhalation therapy, and many others. The Handbook of Atomization and Sprays will bring together the fundamental and applied material from all fields into one comprehensive source. Subject areas included in the reference are droplets, theoretical models and numerical simulations, phase Doppler particle analysis, applications, devices and more.

Download or read book Collision Phenomena in Liquids and Solids written by Alexander L. Yarin and published by Cambridge University Press. This book was released on 2017-06-15 with total page 629 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unique and in-depth discussion uncovering the unifying features of collision phenomena in liquids and solids, along with applications.

Download or read book Turbulent Diffusion in Liquid Jets written by Strong C. Chaung and published by . This book was released on 1974 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atomization of Liquid Jets and Droplets written by Thomas Baron and published by . This book was released on 1949 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Progress In Astronautics and Aeronautics written by Mohammed Habiballah and published by AIAA. This book was released on 2004 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Breakup of a Liquid Jet in a Transverse Flow of Gas written by Bruce J. Clark and published by . This book was released on 1964 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atomization Modeling of Liquid Jets Using an Eulerian Eulerian Model and a Surface Density Approach written by Bejoy Mandumpala devassy and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In internal combustion engines, the liquid fuel injection is an essential step for the air/fuel mixture preparation and the combustion process. Indeed, the structure of the liquid jet coming out from the injector plays a key role in the proper mixing of the fuel with the gas in the combustion chamber. The present work focuses on the liquid jet atomization phenomena under Diesel engine conditions. Under these conditions, liquid jet morphology includes a separate liquid phase (i.e. a liquid core) and a dispersed liquid phase (i.e. a spray). This manuscript describes the development stages of a new atomization model, for a high speed liquid jet, based on an eulerian two-phase approach. The atomization phenomenon is modeled by defining different surface density equations, for the liquid core and the spray droplets. This new model has been coupled with a turbulent two-phase system of equations of Baer-Nunziato type. The process of ligament breakup and its subsequent breakup into droplets are handled with respect to available experiments and high fidelity numerical simulations. In the dense region of the liquid jet, the atomization is modeled as a dispersion process due to the turbulent stretching of the interface, from the side of liquid in addition to the gas side. Different academic test cases have been performed in order to verify the numerical implementation of the model in the IFP-C3D software. Finally, the model is validated with the recently published DNS results under typical conditions of direct injection Diesel engines.

Download or read book Atomization and Sprays written by Arthur Lefebvre and published by CRC Press. This book was released on 1988-12-01 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atomization and Sprays examines the atomization of liquids and characteristics of sprays. It explains the physical processes of atomization as well as guidelines for designing atomizers. In addition, it demonstrates how the importance of the size and velocity of a particle contributes to improved spray characterization. Coverage includes general co

Download or read book Effect of Periodic Oscillations of Velocity and Density of a Medium on Disintegration of Liquid Jets written by I. F. Diti͡akin and published by . This book was released on 1961 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Investigation of the Stability of Liquid Sheet Jets written by Ronald K. Takahashi and published by . This book was released on 1978 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: