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The results of the experiments on the influence of a polyethylene-foam floating thin plate on the process of breaking and regularization of the standing gravity Faraday wave on free water surface in a rectangular vessel are discussed. It is shown that the presence of the plate leads to regularization of the waves with suppression of their breaking mechanisms. The effect of increase in the plate thickness on the limit steepness of the regular flexural-gravity wave and its dissipative properties is considered. The critical plate thickness corresponding to the maximum wave steepness is found. For the plate thickness below this value the vibrations of the hydroelastic system are determined by the gravity waves, while for the greater thickness the vibration mechanism relates to the flexural waves. The non-exponential nature of damping of the flexural-gravity waves is revealed. [ABSTRACT FROM AUTHOR]

The results of the experiments on the influence of a positive-buoyancy-particle layer on the process of breaking and regularization of the standing gravity Faraday wave on free water surface in a rectangular vessel are discussed. The effect of increase in the particle layer thickness on the limit steepness of the regular wave and its dissipative properties is considered. It is shown that the use of highly concentrated polystyrene particle suspension as the upper layer modifies significantly the barotropic wave mode dynamics and ensures regularization of the waves with total suppression of their breaking mechanisms. [ABSTRACT FROM AUTHOR]

The comprehensive experimental analysis of the fluid viscosity effect on the standing gravity waves excited at parametric resonance is carried out. The viscous effects on the frequency range of excitement of the second wave mode, its resonance dependences, and the processes of damping and approaching the steady-state regime are quantitatively estimated by varying the viscosity over a wide range. It is found that the waves are regularized without breaking when the kinematic viscosity of the workingmedium becomes higher than a threshold value. A mechanism of viscous regularization of wave motion is suggested. In accordance with this mechanism, the effects observed experimentally relate to the presence of the shortwave cutoff domain in which viscous dissipation becomes the dominant factor and the shortwave perturbations responsible for breaking the standing wave are suppressed. [ABSTRACT FROM AUTHOR]

Recent observational and modeling evidence has demonstrated that planetary waves can modulate atmospheric tides, and secondary waves arising from their nonlinear interactions are an important source of both temporal and longitude variability in the thermosphere. While significant progress has been made on understanding how this form of vertical coupling occurs, uncertainty still exists on how the horizontal structures of primary and secondary waves evolve with height and the processes responsible for this evolution, in part due to lack of global observations between 120 km and 260 km. In this work we employ a Thermosphere Ionosphere Mesosphere Electrodynamics general circulation model simulation covering all of 2009 that is forced by Modern-Era Retrospective Analysis for Research and Applications dynamical fields, to assess the relative contribution of zonal mean winds and molecular dissipation on the vertical coupling of the eastward propagating diurnal tide with zonal wave number 3 (DE3), the 3 day ultrafast Kelvin wave, and the secondary waves arising from their nonlinear interaction. By developing and applying a new analytic formulation describing the latitudinal structure of an equatorially trapped wave subject to dissipation and background winds, we show that dissipation is the primary contributor to the broadening of the latitudinal structures with height, while asymmetries in the background wind field are responsible for the distortion of the height-latitude structures. [ABSTRACT FROM AUTHOR]

Important physical models involving boundary layer occur in almost all internal and external aerodynamic formations. For many of these, the flow outside the boundary layer region may be determined into a large principal component and a small crosswise velocity. In this article, three-dimensional boundary-layer flow over a curved surface is treated for nanofluid under such a simplification. Based on strong thermal conductivity we have considered two same kinds but different shaped nanoparticle namely: Single Wall Carbon Nanotubes (SWCNT) and Multiple Wall Carbon Nanotubes (MWCNT) which are incorporated within the base fluid water. Mathematical model is constructed under the constraint of defined geometry and then transformed into the system of ordinary differential equations. These equations are solved numerically with the help of Runge Kutta (R-K) method with shooting technique. Influences of each physical parameter on velocity and temperature distribution are described through graphs. To analyze the drag and heat transfer at the surface we have plotted the skin friction coefficient and local Nusselt number. Flow behavior along the stream wise and cross direction is visualized through stream lines. It is found that viscous dissipation has same increasing effects along both x- and z-directions for temperature profile however, SWCNTs have comparatively higher skin friction and heat transfer rate at the surface as compare to the MWNTs. [ABSTRACT FROM AUTHOR]

We study the dynamic evolution of the charge distribution (polarization) of a 2×2 quantum-dot cell with two electrons in the presence of a time-dependent driver cell and a magnetic field. We describe the effects of the magnetic flux on the response of the basic dot cell, for fixed, and linear switching of the driver polarization. In the static case, we find that the magnetic field has a strong localizing effect, similar to the effect of asymmetry. For fixed tunneling, the polarization of the target cell increases with magnetic field, going through a maximum at a particular value of the magnetic flux through the cell. In the dynamic case, a ringing effect and a decrease in the final polarization value of the target cell are obtained as the magnetic field increases. The effects of temperature and asymmetry on these results are also analyzed. [ABSTRACT FROM PUBLISHER]