Harry Swinney
Encyclopedia
Harry L. Swinney is an American
physicist
noted for his contributions to the field of nonlinear dynamics.
in 1961 with a Bachelor degree and obtained his Ph.D. from Johns Hopkins University
in 1968.
He came to the University of Texas at Austin in 1978 and eventually headed the Center for Nonlinear Dynamics.
He is currently the director of the Center for Nonlinear Dynamics at the University of Texas at Austin
.
, most notably for the experiments he did with Jerry Gollub on the onset of turbulence
for water in rotating cylinders (Taylor–Couette flow
). His general research interest have concerned instabilities
, chaos
, pattern formation
, and turbulence in systems driven away from equilibrium
by the imposition of gradients in temperature
, velocity
, concentration
, etc.
His past research concerned:
His current research topics include:
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
noted for his contributions to the field of nonlinear dynamics.
Biography
Swinney graduated from Rhodes CollegeRhodes College
Rhodes College is a private, predominantly undergraduate, liberal arts college located in Memphis, Tennessee, USA. Originally founded by freemasons in 1848, Rhodes became affiliated with the Presbyterian Church in 1855. Rhodes enrolls approximately 1,700 students pursuing bachelor's and master's...
in 1961 with a Bachelor degree and obtained his Ph.D. from Johns Hopkins University
Johns Hopkins University
The Johns Hopkins University, commonly referred to as Johns Hopkins, JHU, or simply Hopkins, is a private research university based in Baltimore, Maryland, United States...
in 1968.
He came to the University of Texas at Austin in 1978 and eventually headed the Center for Nonlinear Dynamics.
He is currently the director of the Center for Nonlinear Dynamics at the University of Texas at Austin
University of Texas at Austin
The University of Texas at Austin is a state research university located in Austin, Texas, USA, and is the flagship institution of the The University of Texas System. Founded in 1883, its campus is located approximately from the Texas State Capitol in Austin...
.
Work
Swinney was among one of the pioneers in chaos theoryChaos theory
Chaos theory is a field of study in mathematics, with applications in several disciplines including physics, economics, biology, and philosophy. Chaos theory studies the behavior of dynamical systems that are highly sensitive to initial conditions, an effect which is popularly referred to as the...
, most notably for the experiments he did with Jerry Gollub on the onset of turbulence
Turbulence
In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by chaotic and stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time...
for water in rotating cylinders (Taylor–Couette flow
Taylor–Couette flow
In fluid dynamics, the Taylor–Couette flow consists of a viscous fluid confined in the gap between two rotating cylinders. For low angular velocities, measured by the Reynolds number Re, the flow is steady and purely azimuthal. This basic state is known as circular Couette flow, after Maurice...
). His general research interest have concerned instabilities
Instability
In numerous fields of study, the component of instability within a system is generally characterized by some of the outputs or internal states growing without bounds...
, chaos
Chaos theory
Chaos theory is a field of study in mathematics, with applications in several disciplines including physics, economics, biology, and philosophy. Chaos theory studies the behavior of dynamical systems that are highly sensitive to initial conditions, an effect which is popularly referred to as the...
, pattern formation
Pattern formation
The science of pattern formation deals with the visible, orderly outcomes of self-organisation and the common principles behind similar patterns....
, and turbulence in systems driven away from equilibrium
Dynamic equilibrium
A dynamic equilibrium exists once a reversible reaction ceases to change its ratio of reactants/products, but substances move between the chemicals at an equal rate, meaning there is no net change. It is a particular example of a system in a steady state...
by the imposition of gradients in temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
, velocity
Velocity
In physics, velocity is speed in a given direction. Speed describes only how fast an object is moving, whereas velocity gives both the speed and direction of the object's motion. To have a constant velocity, an object must have a constant speed and motion in a constant direction. Constant ...
, concentration
Concentration
In chemistry, concentration is defined as the abundance of a constituent divided by the total volume of a mixture. Four types can be distinguished: mass concentration, molar concentration, number concentration, and volume concentration...
, etc.
His past research concerned:
- chaos and pattern formation in flow between concentric rotating cylinders (the Taylor–CouetteTaylor–Couette flowIn fluid dynamics, the Taylor–Couette flow consists of a viscous fluid confined in the gap between two rotating cylinders. For low angular velocities, measured by the Reynolds number Re, the flow is steady and purely azimuthal. This basic state is known as circular Couette flow, after Maurice...
system) - chaos and strange attractors in oscillating chemical reactions
- a laboratory model of JupiterJupiterJupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
's Great Red Spot - a laboratory model of the atmospheric "blocking" phenomenon
- turbulence in buoyancy driven convectionConvectionConvection is the movement of molecules within fluids and rheids. It cannot take place in solids, since neither bulk current flows nor significant diffusion can take place in solids....
; pattern formation in surface-tension-driven (MarangoniMarangoni effectThe Marangoni effect is the mass transfer along an interface between two fluids due to surface tension gradient...
) convection - growth of metallic fractalFractalA fractal has been defined as "a rough or fragmented geometric shape that can be split into parts, each of which is a reduced-size copy of the whole," a property called self-similarity...
clusters in electrodepositionElectrodepositionElectrodeposition may refer to:*Electroplating*Electrophoretic deposition*Underpotential deposition... - chemical patterns of the type predicted by Alan TuringAlan TuringAlan Mathison Turing, OBE, FRS , was an English mathematician, logician, cryptanalyst, and computer scientist. He was highly influential in the development of computer science, providing a formalisation of the concepts of "algorithm" and "computation" with the Turing machine, which played a...
in his 1952 paper "The Chemical Basis for MorphogenesisMorphogenesisMorphogenesis , is the biological process that causes an organism to develop its shape...
" - other patterns in chemical reaction-diffusion systems, including reactions that are periodically forced in time, where Arnold tongue type phase diagrams have been found
- vertically oscillated containers of grains (sand, metallic particles, etc.), which exhibit square, stripe, hexagon, spiral, and oscillonOscillonIn physics, an oscillon is a soliton-like phenomenon that occurs in granular and other dissipative media. Oscillons in granular media result from vertically vibrating a plate with a layer of uniform particles placed freely on top...
(localized) patterns.
His current research topics include:
- shock wavesShock WavesShock Waves, , is a 1977 horror movie written and directed by Ken Wiederhorn...
in supersonic sand - the determination of statistical properties of rapid granular flows, where the observations are compared to the predictions of kinetic theoryKinetic theoryThe kinetic theory of gases describes a gas as a large number of small particles , all of which are in constant, random motion. The rapidly moving particles constantly collide with each other and with the walls of the container...
and continuum theory - instabilities in fluidized bedFluidized bedA fluidized bed is formed when a quantity of a solid particulate substance is placed under appropriate conditions to cause the solid/fluid mixture to behave as a fluid. This is usually achieved by the introduction of pressurized fluid through the particulate medium...
s, where a fluid flows upward through a granular bed, such as in a gasoline refinery catalytic cracker - viscous fingeringViscous fingeringViscous fingering is the formation of patterns in a morphologically unstable interface between two fluids in a porous medium or in a Hele-Shaw cell. It occurs when a less viscous fluid is injected displacing a more viscous one...
patterns at the interface between immiscible fluids - buckling of thin sheets (plastic, leaves of plants)
- scaling and transport in rapidly rotating turbulent flows, such as those in oceanOceanAn ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...
s and atmosphereAtmosphereAn atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...
s.