Location of Repository

In this thesis the following aspects have been investigated:\ud (i) the numerical solutions for unsteady 2-dimensional,\ud incompressible viscous fluid flows induced by a harmonically\ud oscillating cascade, and (ii) the fluid flows in industrial cyclones and their separation efficiencies. In the first part of the thesis we deal with fluid flows induced by harmonically oscillating cascades of cylinders with different cross sectional shapes. Numerical solutions for large amplitude oscillations of a cascade of normal flat plates are obtained by using a finite-difference method\ud and it is found that solutions are in good agreement with some related experimental results. For small amplitude oscillations a perturbation method, series truncation technique and finite-difference methods are used to obtain solutions for cascades of normal flat plates and square cylinders. By assuming that the streaming Reynolds number is 0(1) then the outer streaming flows for cascades of square cylinders, normal flat plates and circular\ud cylinders are investigated numerically for the streaming Reynolds number Rs up to 70. Conformal mapping, grid generation and boundary element methods are used to deal with the different geometries in order to determine the outer potential flows. For small values of the streaming Reynolds number it is found experimentally that the\ud flow remains symmetrical and the numerically predicted fluid flow is in good agreement with the experimental results. As the value of the streaming Reynolds number increases then it is found experimentally that the flow develops asymmetries and this occurs when 8<R <9, and\ud the numerically predicted results are also in good agreement with the experimental data. A stability analysis is presented for the outer streaming flow for the cascade of circular cylinders which reveals the reasons for the break-down in the symmetry.\ud \ud In the second part of the thesis the fluid flow In industrial cyclones has been investigated numerically. The influence of various aspects of the design parameters of the cyclone have been studied numerically and some important factors which affect the separation\ud efficiency of the cyclone are identified. Numerical results are also compared with some existing experimental data and there is good agreement. Correlations for both the loss factor and d50, the 50% cut-off particle diameter, with other parameters and operating conditions of the cyclone performance have been developed using a regression method with the existing experimental results. Finally,\ud the separation efficiency of a small personal cyclone (10mm in diameter) is also investigated

Publisher: Applied Mathematics (Leeds)

Year: 1991

OAI identifier:
oai:etheses.whiterose.ac.uk:435

Provided by:
White Rose E-theses Online

Downloaded from
http://etheses.whiterose.ac.uk/435/1/uk_bl_ethos_405919.pdf

- 1831, On a Peculiar Class of Acoustical Figures and on Certain Forms Assumed by Groups of Particles upon Vibrating Elastic Surfaces,
- 1874, Ueber die Entstehungsweiseder Kundt's chen Staubfiguren, Ann. der Phys.
- 1883, On the Circulations of Air Observed in Kundt's Tubes and on Some Allied Acoustical Problems,
- 1990a, Steady Two-dimensional Flow through a Row of Normal Flat Plates,
- (1990). A - 285 -Numerical Investigation into the Fluid Dynamics in a Cyclone,
- (1978). A Difference Method for Solving the Navier-Stokes Equations,
- (1979). A Five-stage Cyclone System for in Situ Sampling,
- (1982). A Fundamental Mathematical Modelling Approach to Cyclone Design,
- (1967). A Gravimetric Size-selecting Personal Dust Sampler, Inhaled Particles S Vapours II (Edited by
- (1970). A Matrix Method for Ordinary Differential Eigenvalue Problems,
- (1954). A Note on the Numerical Solution of Fourth Order Differential Equations,
- (1990). A Numerical Study of The Fluid and Particle Collection in Cyclones,
- (1952). A Study of the Motion of Solid Particles in a Hydraulic Cyclone,
- (1990). A Visual Study of the Flow Around an Oscillating Circular Cylinder at
- (1953). Acoustic Streaming at Low Reynolds Number,
- (1954). Acoustical Streaming in the Vicinity of a Cylinder,
- (1955). Acoustical Streaming in the Vicinity of a Sphere,
- (1980). An Analysis of Boundary Layer Effects in a Hydrocyclone,
- (1974). An Experimental Investigations of High - 276 Reynolds Number Steady Streaming Generated by Oscillating Cylinders,
- (1967). An Introduction to Fluid Dynamics,
- (1929). Analyse Ultramicroscopique Des Vibrations Mriennes,
- (1961). Application of Conformal Mapping to Viscous Flow Between Moving Circular Cylinders,
- (1974). Automatic Numerical Grid Generation of Body Fitted Curvilinear Coordinate System For Field Containing Any Number of Arbitrary Two Dimensional Bodies,
- (1954). Boundary Layer Flow Near A Cylindrical Obstacle in an Oscillating Incompressible Fluid,
- (1973). Circulatory Streaming Around an Oscillating Circular Cylinder at Low Reynolds Numbers,
- (1974). Circulatory Streaming in the Vicinity of an Oscillating Square Cylinder,
- (1990). Comparison of Respirable Dust Sampler Penetration Curves with Sampling Conventions, private communication to
- (1988). Construction and Testing of an Axial Flow Cyclone Preseparators,
- (1949). Cyclone Operating Factors and Capacities on Coal and Refuse Slurries,
- (1966). Double Boundary Layers in Oscillating Viscous Flows,
- (1982). Finite Element Analysis of Viscous Flow
- (1959). Flow Patterns in the Hydraulic Cyclone and Their Interpretation in Terms of Performance,
- (1964). Flows Around Dihedral Angles,
- (1986). Flows Pass Arrays of Cylinders, Ph. D Thesis,
- (1991). Fluid Flow Induced by a Small Amplitude Harmonically Oscillating Cascade, Accepted for Publication in Acta Mechanica.
- (1988). Force on Oscillating Bodies in Viscous Fluids,
- (1984). Generalized Performance Characteristics of Miniature Cyclones for Atmospheric Particulate Sampling,
- (1981). High Reynolds Number Flow with Closed Streamlines,
- (1949). Investigations into Cyclone Dust Collectors,
- (1972). Jets Induced by Oscillatory Motion,
- (1964). Laminar Flow Theory, Section D, Chapter 2,
- (1988). Low-frequency Oscillation of a Cylinder in a Viscous Fluid,
- (1958). Motion of Water in a Hydraulic Cyclone,
- (1990). Nonlinear Flow Phenomena in a Symmetrical Sudden Expansion,
- (1973). Nonlinear Streaming Effects Associated with Oscillating Cylinders,
- (1985). Numerical and Asymptotic Solutions for Merging Flow Through a Channel with an Upstream Splitter Plate,
- (1978). Numerical Calculations on Viscous Flow Fields Through Cylinder Arrays,
- (1967). Numerical Methods for Hydrodynamic Stability Problems,
- (1968). On High Frequency Oscillatory Viscous Flows,
- (1985). On Large-scale Eddy Closure,
- (1956). On Steady Laminar Flow with Closed Streamlines at Large Reynolds Number,
- (1931). On the Circulations Caused by the Vibration of Air in a Tube,
- (1988). On the Hydrodynamic Interaction of Two Circular Cylinders Oscillating in a Viscous Fluid,
- (1982). On the Hydrodynamic Interaction of Two Spheres Oscillating In a Viscous Fluid -I. Axisymmetrical Case,
- (1967). Oscillatory Viscous Flows, Review &
- (1961). Performance and Design of
- (1987). Periodic Solutions on Rigid Body-Viscous Flow Interaction,
- (1984). Plane-Sudden Expansion Flows & Their Stability, Ph-D Thesis,
- (1974). Secondary Flow Around an Oscillating Cylinder,
- (1980). Secondary Flows Around Oscillating Asymmetrical Cylinders,
- (1985). Sinusoidal Flow Relative to Circular Cylinders,
- (1973). Size Selection Characteristics of the Cyclone Used
- (1967). Stability of Parallel Flows,
- (1980). Steady Flow Through a Channel with a Symmetrical Constriction In the Form of a Step,
- (1991). Streaming Flow Induced by an Oscillating Cascade of Circular Cylinders,
- (1991). Streaming Flow Induced by an Oscillating Cascade of Cylinders,
- (1989). Streaming Flows Generated by High-Frequency Small-amplitude Oscillations of Arbitrarily Shaped Cylinders,
- (1989). Swirling Flows in Conical Vessels, Ph. D Thesis,
- (1986). The Design and Performance of Cyclone Separators,
- (1980). The Effect of Particle Concentration on the Boundary Layer Flow in a Hydrocyclone,
- (1980). The Effect of Solids on the Boundary Layer in a Hydrocyclone, Ph. D Thesis,
- (1989). The Fluid Flow Induced by an Oscillating Cascade,
- (1990). The Fluid Flow Induced by Large Amplitude Oscillations of a Cascade, Accepted for Publication in Computer & Fluids.
- (1965). The Hydrocyclone, 1st Ed., Pergammon,
- (1953). The Hydrocyclone, its Application and its Explanation,
- (1962). The Influence of Some Variables upon Hydrocyclone Performance,
- (1974). The Least-squares Fitting of Cubic Spline Surfaces to General Data Sets,
- (1984). The Numerical Solution of 2-dimensional Flow in a Branching Channel,
- (1979). The Steady Streaming Induced Between Oscillating Circular Cylinders,
- (1975). The Steady Streaming Induced by a Vibrating Cylinder,
- (1974). The Theoretical Analysis of the Conical Cyclone,
- (1946). The Treatment of Singularities of Partial Differential Equations by Relaxation Methods,
- (1973). The Velocity Distribution within a Hydrocyclone Operating without an Air Core, The Canadian
- (1975). Turbulent Spin in a Cyclone,
- (1963). Unsteady Boundary Layer. In: Laminar Boundary Layers,
- (1981). Unsteady Viscous Flows,
- (1964). Viscous and Resistive Eddies near a Sharp Corner,