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Showing 1 to 19 of 19 for “"wave instability"”.
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Density-Wave Instability Characterization in Boiling Water Reactors under MELLLA+ Domain during ATWS
Density wave oscillations (DWO) are a class of two-phase flow instabilities which can pose significant safety concerns to boiling water reactors (BWR). During an anticipated transient without scram (ATWS) while operating in the proposed extended operating domain MELLLA+, natural circulation …
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A Correlated 1-D Monatomic Condensed Matter System: Experiment and Theory
… that this 1-D system undergoes a charge density wave instability, which is a first for such a 1-D phenomenon on a metallic substrate. It is determined experimentally that this 1-D system undergoes an electronic phase transition at a temperature of about 85K, in which the higher temperature …
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Two-Dimensional Transient Flows and Stability of Concentrated Suspensions of Clay Particles and Rheology
… are taken for insight of physical aspects. Long-wave instability of a fast, continuous, uniform flow down a slope is analyzed. The threshold for long-wave instability to occur is determined by the relative thickness of plug layer lambda and the dynamic parameter beta, and stable zones are …
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Instabilities of finite-width internal wave beams
Internal gravity waves are fundamental to the dynamics of density stratified fluids and the instability mechanisms by which these waves dissipate their energy are a potentially significant factor that underlies the distribution of energy and momentum in the natural environment. Recently, it has …
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The stability and control of curved liquid jet break-up
… concerning break-up of a ligament and short wave generation at break-up is discussed. The Needham-Leach method is adopted to obtain the behaviour of linear and nonlinear waves in the large spatial and temporal limits. The onset of nonlinear wave instability as an implication in satellite drop …
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The stability and control of curved liquid jet break-up
… concerning break-up of a ligament and short wave generation at break-up is discussed. The Needham-Leach method is adopted to obtain the behaviour of linear and nonlinear waves in the large spatial and temporal limits. The onset of nonlinear wave instability as an implication in satellite drop …
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Interfaces between Competing Patterns in Reaction-diffusion Systems with Nonlocal Coupling
… nonlocal coupling term. This model exhibits a wave instability for slow inhibitor diffusion, while, for fast inhibitor diffusion, a Turing instability is found. For moderate values of the inhibitor diffusion these two instabilities occur simultaneously at a codimension-2 wave-Turing …
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Applied fractionalization : quantum phases and phase transitions of strongly interacting systems
… different from the conventional spin-density wave instability of Fermi surface.
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Shear flow instabilities in viscoelastic fluids
… We begin part I with a previously known short-wave instability of Upper Convected Maxwell and Oldroyd–B fluids at zero Reynolds number in Couette flow. We show that if the Weissenberg number is large, the instability persists with the same growth rate when the wavelength is longer than the …
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On the stability of plane viscoelastic shear flows in the limit of infinite Weissenberg and Reynolds numbers
Elastic effects on the hydrodynamic instability of inviscid parallel shear flows are investigated through a linear stability analysis. We focus on the upper convected Maxwell model in the limit of infinite Weissenberg and Reynolds numbers. Specifically, we study the effects of elasticity on the …
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Thermonuclear Driven Fast Magnetosonic Wave Heating in Tokamak Plasmas
A thermonuclear driven fast magnetosonic wave instability is investigated in tokamak plasmas for propagation transverse to the external magnetic field at frequencies of several times the alpha particle gyro rate: (omega)(TURNEQ)L(OMEGA)(, ) =k(,(PERP))v(,A), L(TURN)4 to 8, k(,(PARLL))<<k(,(PERP)). …
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Magnetohydrodynamics in the Inner Regions of Protoplanetary Discs
… a pressure maximum that triggers the Rossby wave instability, producing vortices whose coherence is weakened by turbulence at the interface. Meanwhile, the dead zone develops a magnetic field of a distinct morphology – likely diffused outward from the active zone – consistent with that …
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Disc-planet interactions in inviscid discs
… to the excitation of global spiral density waves, which drive evolution of the disc (such as the opening of gaps) and the planets’ orbital properties (known as migration). Modern observations of PPDs, provided for example by the high resolution interferometer ALMA, have shown intriguing …
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Dynamics of Turbulence and Flows in a Helicon Plasma Under Electrode Biasing
… was a hybrid mode between the Kelvin-Helmholtz instability and the drift-wave instability. The generation of this hybrid mode is believed to be caused by changes in the axial parameters, particularly the density and potential gradients. In order to affect these fluctuations, and explore the …
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Aggregation, Spatio-Temporal Structures and Well-Posedness in Chemotaxis Models of Inflammatory Diseases
L'infiammazione è la risposta immunitaria dell'organismo a uno stimolo nocivo. Il suo scopo è prevenire l'insorgere di malattie. Sebbene sia un meccanismo protettivo, un disordine della risposta infiammatoria può portare a malattie gravi e debilitanti, come la sclerosi multipla. Per questo …
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Mathematical problems arising in interfacial electrohydrodynamics
… are used to derive fully nonlinear long wave model equations for the scaled interface motion and corresponding flow fields. For the case of an inclined plane, higher order terms are need to be retained to regularize the problem in the sense that the long wave approximation remains valid …
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Computation of the rise or fall of a drop through a suspending liquid with no mass transfer: Axisymmetric, transitional and complex regimes
… circular interface, damped capillary waves. We also consider relaxation to Laplace’s equilibrium for a spherical interface, neglecting mesh and interface motion. Two different approaches to account for interfacial tension are demonstrated for the spherical interface: one using …
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Experimental investigation of two-phase instability in natural circulation with direct transient local measurement
… systems can be susceptible to thermal hydraulic instability under specific circumstances. Proper handling of the stability problem under natural circulation is critical for the reactor safety and operation under important conditions such as the start-up transient of natural circulation cooled …