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Wave patterns, modeling

The possibility that the climatic future might feature a change in frequency of weather extremes underscores the desirability for climate models capable of predicting the future spectrum of prevailing circulation patterns. Weather extremes such as drought or excessive cold are the products of certain persistent (blocking) planetary wave patterns. In fact, it is reasonable to assume that past climatic... [Pg.385]

In what follows we will discuss systems with internal surfaces, ordered surfaces, topological transformations, and dynamical scaling. In Section II we shall show specific examples of mesoscopic systems with special attention devoted to the surfaces in the system—that is, periodic surfaces in surfactant systems, periodic surfaces in diblock copolymers, bicontinuous disordered interfaces in spinodally decomposing blends, ordered charge density wave patterns in electron liquids, and dissipative structures in reaction-diffusion systems. In Section III we will present the detailed theory of morphological measures the Euler characteristic, the Gaussian and mean curvatures, and so on. In fact, Sections II and III can be read independently because Section II shows specific models while Section III is devoted to the numerical and analytical computations of the surface characteristics. In a sense, Section III is robust that is, the methods presented in Section III apply to a variety of systems, not only the systems shown as examples in Section II. Brief conclusions are presented in Section IV. [Pg.143]

Now possibilities of the MC simulation allow to consider complex surface processes that include various stages with adsorption and desorption, surface reaction and diffusion, surface reconstruction, and new phase formation, etc. Such investigations become today as natural analysis of the experimental studying. The following papers [282-285] can be referred to as corresponding examples. Authors consider the application of the lattice models to the analysis of oscillatory and autowave processes in the reaction of carbon monoxide oxidation over platinum and palladium surfaces, the turbulent and stripes wave patterns caused by limited COads diffusion during CO oxidation over Pd(110) surface, catalytic processes over supported nanoparticles as well as crystallization during catalytic processes. [Pg.434]

The nuclear concentration of mass anticipated Rutherford s model of the atom, and Bohr s planetary model by a decade. The spectral integers, linked to a standing-wave pattern, predates de Broglie s proposal by two decades. [Pg.40]

Schrodinger and Bohm both accepted that quantum motion follows a wave pattern. To account for wave-particle dualism the interpretation of matrix mechanics, developed by Heisenberg and others, was extended on the assumption of probability densities. Schrodinger developed the notion of wave structures to simulate particle behaviour, but this model has been rejected almost universally and apparently irretrievably, in favour of proba-bities, arguably prematurely and for questionable reasons. Bohm s attempt to revive the wave interpretation advocated a literary interpretation of wave-particle dualism in the form of a classical particle accompanied and piloted by a quantum wave. [Pg.85]

The N-NDR prototype model possesses also a small parameter regime close to the Hopf bifurcation in which the spatiotemporal picture becomes much richer. Depending on the conductivity of the electrolyte and the size of the electrodes either comparatively regular wave patterns with a low wave number or turbulent looking patterns with much higher wave number establish [34, 172],... [Pg.159]

Figure 11. Wave patterns on rivulet interface depending on wall superheat, value as for creeping flow model. Figure 11. Wave patterns on rivulet interface depending on wall superheat, value as for creeping flow model.
Figure 10 presents the interface shape of the rivulet for wall superheat as 0.5 K and Re = 2.5. Here also presented the data on pressure in liquid and heat flux density in rivulet cross-section. The intensive liquid evaporation in near contact line region causes the interface deformation. As a result the transversal pressure gradient creates the capillarity induced liquid cross flow in direction to contact line. Finally the balance of evaporated liquid and been bring by capillarity is established. This balance defines the interface shape and apparent contact angle value.For the inertia flow model, the solution is obtained from a non-stationary system of equations, i.e., it is time-dependable. In this case the disturbances in flow interface can create the wave flow patterns. The solutions of unsteady state liquid spreading on heat transfer surface without and with evaporation are presented on Fig. 11. When the evaporation is not included (for zero wall superheat) the wave pattern appears on the interface. When the evaporation includes, the apparent contact angle increase immediately and deform the interface. It causes the wave suppression due to increasing of the film curvature. Figure 10 presents the interface shape of the rivulet for wall superheat as 0.5 K and Re = 2.5. Here also presented the data on pressure in liquid and heat flux density in rivulet cross-section. The intensive liquid evaporation in near contact line region causes the interface deformation. As a result the transversal pressure gradient creates the capillarity induced liquid cross flow in direction to contact line. Finally the balance of evaporated liquid and been bring by capillarity is established. This balance defines the interface shape and apparent contact angle value.For the inertia flow model, the solution is obtained from a non-stationary system of equations, i.e., it is time-dependable. In this case the disturbances in flow interface can create the wave flow patterns. The solutions of unsteady state liquid spreading on heat transfer surface without and with evaporation are presented on Fig. 11. When the evaporation is not included (for zero wall superheat) the wave pattern appears on the interface. When the evaporation includes, the apparent contact angle increase immediately and deform the interface. It causes the wave suppression due to increasing of the film curvature.
B. Model of wave patterns affecting One Tree Reef in east-southeasterly... [Pg.155]

The first part eoncerns the generation of the residuals (waved pattern in the Figure 1). In order to obtain an observer of the physical system, a real-time simulation is done in parallel. So, a eomplete state of the system will be available at any time. Thus, it is based on the eomparison between the predicted behavior obtained thanks to the simulation of the reference model (values of state variables) and the real observed behavior (measurements from the process correlated thanks to the Extended Kalman Filter). The main idea is to reconstruct the outputs of the system from the measurement and to use the residuals for fault detection (Mehra and Peschon, 1971, Welch and Bishop, 1995, Simani and Fantuzzi, 2006). A description of the extended Kalman filter ean be found in (Olivier-Maget et al., 2007). Besides the residual is defined aeeording to the following equation ... [Pg.413]

The distribution of the electric fields along z-axis in the air-model film-Al system is shown in Fig. 1.16b. The standing-wave patterns produced by the tangential electric field components exhibit nodes at a metal surface, while the normal component has an antinode. As seen from the insert in Fig. 1.16i>, the tangential electric fields, which are continuous at interfaces (1.8.8°), decay dramatically after crossing the metal surface, typically at a distance similar to the depth of the skin layer (1.3.14°). [Pg.53]

Various traveling wave patterns are found when g is less than g, a value that depends on the initial concentrations of reagents. When the feedback coefficient exceeds g, cluster patterns can occur. Clusters consist of sets of domains in which nearly all of the elements in a domain oscillate with the same amplitude and phase (18-19). Clusters have been observed in model studies of arrays of coupled neurons (20), but they are rare in chemical systems. In the simplest case, a system consists of two clusters that oscillate 180° out of phase each cluster can consist of several spatial domains. [Pg.110]

Figure 6.2 shows an example of a traveling wave pattern in a one-dimensional Brusselator model. [Pg.113]

Flumes are two-dimensional (2D) and basins are 3D. Thus, basins have more parameters (relative to the 3D) that can be varied relative to flumes. The dimensions of the flume or basin must be adequate for the desired model scale. Scales are often smaller in flumes since the walls may be higher and the wavemaker has a longer stroke. Flumes can have wall effects due to the relative closeness of the flume sides, however. Waves can only be unidirectional in flumes. Flumes often have viewing transparent (plexiglass) windows for observing the wave patterns and transformation. [Pg.1079]

The above classical detonation theory was proposed by Zebdovich [529, 530, 534] (see also [334]), Doring [113] and Grib [169] on the basis of a unidimensional model of a stationary detonation wave. Further studies showed (for references see Strehlow s review [458, 535]) that the real gas-kinetic and the chemical-kinetic pattern of a detonation wave are much more complicated than the idealized plane shock wave. Moreover, the flat chemical reaction fronts which follow from the classical theory are non-stationary, thus leading to distortions and discontinuities in the flame front resulting in the violation of the idealized detonation wave pattern. [Pg.223]


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See also in sourсe #XX -- [ Pg.176 , Pg.177 , Pg.178 , Pg.179 , Pg.180 , Pg.181 ]




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