POF: Geophysical Flows http://scitation.aip.org/ POF: Geophysical Flows Fluid flows in a librating cylinder http://link.aip.org/link/?PHF/24/026603/1&agg=rss Alban Sauret, David Cebron, Michael Le Bars, and Stephane Le Dizes<br/> The flow in a cylinder driven by time-harmonic oscillations of the rotation rate, called longitudinal librations, is investigated. Using a theoretical approach and axisymmetric numerical simulations, we study two distinct phenomena appearing in this librating flow. First, we investigate the occurren ... [Phys. Fluids 24, 026603 (2012)] published Tue Feb 7, 2012. Dipole evolution in rotating two-dimensional flow with bottom friction http://link.aip.org/link/?PHF/24/026602/1&agg=rss V. G. Makarov<br/> The evolution of a dipolar vortex in a quasi-two-dimensional rotating flow of barotropic fluid over a flat surface with a no-slip condition in the Ekman bottom layer is considered. The vorticity equation in this case becomes nonlinear. An effect of bottom friction is displayed mainly in cyclone-anti ... [Phys. Fluids 24, 026602 (2012)] published Fri Feb 3, 2012. Multiple zonal jets on the polar beta plane http://link.aip.org/link/?PHF/24/016603/1&agg=rss A. G. Slavin and Y. D. Afanasyev<br/> The mechanism of the formation of multiple quasi-zonal jets as well as their meridional scaling is investigated for a range of control parameters including the radius of deformation and the parameter which characterizes the polar beta-plane. Flows in a rotating cylindrical domain where the depth of ... [Phys. Fluids 24, 016603 (2012)] published Thu Jan 26, 2012. Numerical simulation of mass transport in internal solitary waves http://link.aip.org/link/?PHF/24/016602/1&agg=rss Maher Salloum, Omar M. Knio, and Alan Brandt<br/> A computational study of mass transport by large-amplitude, mode-2 internal solitary waves propagating on a pycnocline between two layers of different densities was conducted. The numerical model is based on the simulation of a vorticity-based formulation of the two-dimensional Navier-Stokes equatio ... [Phys. Fluids 24, 016602 (2012)] published Thu Jan 26, 2012. Instability in internal solitary waves with trapped cores http://link.aip.org/link/?PHF/24/016601/1&agg=rss M. Carr, S. E. King, and D. G. Dritschel<br/> A numerical method that employs a combination of contour advection and pseudo-spectral techniques is used to investigate instability in internal solitary waves with trapped cores. A three-layer configuration for the background stratification in which the top two layers are linearly stratified and th ... [Phys. Fluids 24, 016601 (2012)] published Thu Jan 5, 2012. Large eddy simulation study of scalar transport in fully developed wind-turbine array boundary layers http://link.aip.org/link/?PHF/23/126603/1&agg=rss Marc Calaf, Marc B. Parlange, and Charles Meneveau<br/> Wind harvesting is fast becoming an important alternative source of energy. As wind farms become larger, they begin to attain scales at which two-way interactions with the atmospheric boundary layer (ABL) must be taken into account. Several studies have shown that there is a quantifiable effect of w ... [Phys. Fluids 23, 126603 (2011)] published Tue Dec 20, 2011. Analytical solutions for von Karman streets of hollow vortices http://link.aip.org/link/?PHF/23/126602/1&agg=rss Darren G. Crowdy and Christopher C. Green<br/> New analytical solutions are presented for steadily translating von Karman vortex streets made up of two infinite rows of hollow vortices. First, the solution for a single row of hollow vortices due to Baker et al. ["Structure of a linear array of hollow vortices of finite cross-section," J. Fluid M ... [Phys. Fluids 23, 126602 (2011)] published Wed Dec 14, 2011. Inertial, barotropic, and baroclinic instabilities of the Bickley jet in two-layer rotating shallow water model http://link.aip.org/link/?PHF/23/126601/1&agg=rss Francois Bouchut, Bruno Ribstein, and Vladimir Zeitlin<br/> We undertake a detailed study of inertial instability of the barotropic Bickley jet and its nonlinear saturation in the 2 layer rotating shallow water (RSW) model on the f-plane and compare it with the classical barotropic and baroclinic instabilities. We start with analytical and numerical investig ... [Phys. Fluids 23, 126601 (2011)] published Wed Dec 7, 2011. Higher-order (2 + 4) Korteweg-de Vries-like equation for interfacial waves in a symmetric three-layer fluid http://link.aip.org/link/?PHF/23/116602/1&agg=rss O. E. Kurkina, A. A. Kurkin, T. Soomere, E. N. Pelinovsky, and E. A. Rouvinskaya<br/> We address a specific but possible situation in natural water bodies when the three-layer stratification has a symmetric nature, with equal depths of the uppermost and the lowermost layers. In such case, the coefficients at the leading nonlinear terms of the modified Korteweg-de Vries (mKdV) equatio ... [Phys. Fluids 23, 116602 (2011)] published Fri Nov 18, 2011. Resonant generation of internal waves by short length scale topography http://link.aip.org/link/?PHF/23/116601/1&agg=rss Marek Stastna<br/> We consider the resonant generation of internal waves by small-amplitude topography with multiple local maxima. We demonstrate that for near-critical inflows, the initial resonant generation process is locked to the topography. However, the process undergoes a profound reorganization in the long tim ... [Phys. Fluids 23, 116601 (2011)] published Thu Nov 17, 2011. Experimental observation of standing interfacial waves induced by surface waves in muddy water http://link.aip.org/link/?PHF/23/096603/1&agg=rss Eric Maxeiner and Robert A. Dalrymple<br/> A striking feature has been observed in a laboratory wave tank with a thin layer of clear water overlying a layer of mud. A piston-type wave maker is used to generate long monochromatic surface waves in a tank with a layer of kaolinite clay at the bottom. The wave action on the mud causes the clay p ... [Phys. Fluids 23, 096603 (2011)] published Wed Sep 28, 2011. Breaking internal wave groups: Mixing and momentum fluxes http://link.aip.org/link/?PHF/23/096602/1&agg=rss Daniel A. Birch and Miles A. Sundermeyer<br/> Breaking groups of large-amplitude internal gravity waves are simulated numerically and the resulting diapycnal mixing and residual momentum are quantified. The wave frequency strongly affects the mixing, with high- and low-frequency waves doing many times more mixing than intermediate-frequency wav ... [Phys. Fluids 23, 096602 (2011)] published Wed Sep 21, 2011. Experimental evidence of Alfven wave propagation in a Gallium alloy http://link.aip.org/link/?PHF/23/096601/1&agg=rss Thierry Alboussiere, Philippe Cardin, Francois Debray, Patrick La Rizza, Jean-Paul Masson et al.<br/> Experiments with a liquid metal alloy, Galinstan, are reported and show clear evidence of Alfven wave propagation as well as resonance of Alfven modes. Galinstan is liquid at room temperature and, although its electrical conductivity is not as large as that of liquid sodium or NaK, it has still been ... [Phys. Fluids 23, 096601 (2011)] published Thu Sep 15, 2011. Nonlinear wave evolution and runup in an inclined channel of a parabolic cross-section http://link.aip.org/link/?PHF/23/086602/1&agg=rss Ira Didenkulova and Efim Pelinovsky<br/> Nonlinear wave dynamics of long water waves is studied in an inclined channel of a parabolic cross-section. Such situation occurs when sea waves enter and propagate in a narrow bay or a fjord. Nonlinear shallow water equations can in this case be written in 1D form and solved analytically with the u ... [Phys. Fluids 23, 086602 (2011)] published Mon Aug 15, 2011. Stratified turbulence at the buoyancy scale http://link.aip.org/link/?PHF/23/066602/1&agg=rss Michael L. Waite<br/> Numerical simulations of forced stratified turbulence are presented, and the dependence on horizontal resolution and grid aspect ratio is investigated. Simulations are designed to model the small-scale end of the atmospheric mesoscale and oceanic submesoscale, for which high horizontal resolution is ... [Phys. Fluids 23, 066602 (2011)] published Thu Jun 23, 2011. Kinetic simulations of thermal escape from a single component atmosphere http://link.aip.org/link/?PHF/23/066601/1&agg=rss Alexey N. Volkov, Orenthal J. Tucker, Justin T. Erwin, and Robert E. Johnson<br/> The one-dimensional steady-state expansion of a monatomic gas from a spherical source in a gravity field is studied by the direct simulation Monte Carlo method. Collisions between molecules are described by the hard sphere model, the distribution of gas molecules leaving the source surface is assume ... [Phys. Fluids 23, 066601 (2011)] published Mon Jun 6, 2011. Combined diffusion-driven and convective flow in a tilted square container http://link.aip.org/link/?PHF/23/056602/1&agg=rss Michael A. Page<br/> Asymptotic analytical solutions are derived for the configuration posed by Quon [Phys. Fluids 26, 632 (1983)] for diffusion-driven flow in a tilted square container when the diffusive parameter R is small. The key regions of the asymptotic structure are outlined and the leading-order solutions are d ... [Phys. Fluids 23, 056602 (2011)] published Tue May 31, 2011. Laboratory experiments on two coalescing axisymmetric turbulent plumes in a rotating fluid http://link.aip.org/link/?PHF/23/056601/1&agg=rss H. Yamamoto, C. Cenedese, and C. P. Caulfield<br/> We investigate the early-time coalescence of two co-flowing axisymmetric turbulent plumes and the later-time flow of the induced vortices in a rotating, homogeneous fluid using laboratory experiments. The experiments demonstrate the critical importance of the rotation period T=2pi/f, where f is the ... [Phys. Fluids 23, 056601 (2011)] published Thu May 19, 2011. Simplified two-layer models of precipitating atmosphere and their properties http://link.aip.org/link/?PHF/23/046603/1&agg=rss J. Lambaerts, G. Lapeyre, V. Zeitlin, and F. Bouchut<br/> We derive a two-layer rotating shallow-water model for a moist atmosphere with water vapor condensation and related diabatic heating. Moist convection is represented by additional mass exchanges between the layers, which are determined from the moist enthalpy conservation principle, and related to t ... [Phys. Fluids 23, 046603 (2011)] published Tue Apr 26, 2011. Steady transcritical flow over an obstacle: Parametric map of solutions of the forced extended Kortewegde Vries equation http://link.aip.org/link/?PHF/23/046602/1&agg=rss Bernard K. Ee, R. H. J. Grimshaw, K. W. Chow, and D-H. Zhang<br/> Transcritical flow of a stratified fluid over an obstacle is often modeled by the forced Kortewegde Vries equation, which describes a balance among weak nonlinearity, weak dispersion, and small forcing effects. However, in some special circumstances, it is necessary to add an additional cubic nonlin ... [Phys. Fluids 23, 046602 (2011)] published Thu Apr 21, 2011. Convergent flow in a two-layer system and plateau development http://link.aip.org/link/?PHF/23/046601/1&agg=rss Julio Gratton and Carlos Alberto Perazzo<br/> In order to describe the development of plateaus such as the Tibet and the Altiplano we extend the two-layer model used in a previous paper [C. A. Perazzo and J. Gratton, Phys. Fluids 22, 056603 (2010)] to reproduce the evolution of mountain ranges. As before, we consider the convergent motion of a ... [Phys. Fluids 23, 046601 (2011)] published Mon Apr 11, 2011.