Article
Mechanics
David Cebron, Jeremie Vidal, Nathanael Schaeffer, Antonin Borderies, Alban Sauret
Summary: The study investigates the generation mechanism of mean zonal flows in rapidly rotating fluid-filled spheroids, with theoretical predictions validated by numerical simulations. It further considers the impact of spatial and temporal perturbations, as well as spheroidal geometry on the zonal flows.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Xuan Zhang, Robert E. Ecke, Olga Shishkina
Summary: In rapidly rotating turbulent Rayleigh-Benard convection with a small Prandtl number fluid in slender cylindrical containers, a boundary zonal flow (BZF) is found to develop near the sidewall, carrying a disproportionate amount of heat transport for Pr < 1 but decreasing abruptly for larger Pr. The BZF is robust and appears in containers of different aspect ratios and over a broad range of Pr and Ra values.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Yufeng Lin, Andrew Jackson
Summary: This study focuses on the dynamics of Boussinesq convection in a rotating full sphere, particularly on the development of large-scale coherent structures and mean zonal flows. The research reveals the critical role of the convective Rossby number in the formation and transition of large-scale vortices.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Geochemistry & Geophysics
Taylor L. Lonner, Ashna Aggarwal, Jonathan M. Aurnou
Summary: This study simulates turbulent convection in a planet's outer core using a thermally-driven, free surface paraboloidal laboratory annulus. The researchers found that the dynamics of rapidly rotating convection in free-surface paraboloidal annuli are similar to those in planetary spherical shell geometries. The experiments showed the presence of thermal Rossby waves and multiple azimuthal jets, with more jets forming at higher rotation rates. The migration of the jets and the flux of energy into larger-scale zonal flow structures were also observed. The effects of ambient magnetic fields on such turbulent flows remain unknown.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2022)
Article
Mechanics
Nathan Paldor, David G. Dritschel
Summary: The study examines the late-time evolution of an inviscid zonally symmetric shallow-water flow on the surface of a rotating spherical earth and compares it to the simpler problem of uniformly rotating shallow-water flow on a plane. Despite waves on a sphere unable to propagate to infinity, a form of adjustment still takes place in a time-averaged sense, similar to geostrophic balance in the planar case.
Article
Astronomy & Astrophysics
Yufeng Lin, Jerome Noir
Summary: This study investigates the fluid motions in planetary bodies undergoing forced libration in our solar system. The numerical simulations reveal the dependencies of shear layers on Ekman numbers when the libration frequency is less than twice the rotation frequency. The results suggest that inertial waves formed at critical latitudes contribute to the formation of conical shear layers in longitudinally librating spherical shells.
GEOPHYSICAL AND ASTROPHYSICAL FLUID DYNAMICS
(2021)
Article
Optics
Quan Sheng, Aihua Wang, Jingni Geng, Shijie Fu, Yuanyuan Ma, Wei Shi, Jianquan Yao, Takashige Omatsu, David Spence
Summary: In this study, ultra-high-order LG beams with m beyond 300 were generated using the spherical aberration of a lens in a simple end-pumped Nd:YVO4 laser at 1064 nm, providing a simple and flexible method to convert a wide range of lasers to generate ultra-high-order LG modes.
LASER & PHOTONICS REVIEWS
(2023)
Article
Physics, Fluids & Plasmas
Robert E. Ecke, Xuan Zhang, Olga Shishkina
Summary: Using direct numerical simulations, this study investigates rotating Rayleigh-Benard convection and connects linear wall-mode states with the boundary zonal flow in the geostrophic regime. The data from various sources are quantitatively collapsed, providing insights into the heat transport contributions of the wall modes and boundary zonal flow.
PHYSICAL REVIEW FLUIDS
(2022)
Article
Optics
Huan Tang, Renxian Li, Shuhong Gong, Liu Yang, Lixia Yang, Bing Wei, Zitong Zhu, F. G. Mitri
Summary: By investigating the interaction between a dielectric circular cylinder rotating at a stable angular velocity and a plane wave, the curved photonic nanojet (CPNJ) phenomenon is studied. The optical Magnus effect of the dielectric circular cylinder is verified, and the analytical expressions for the internal and external electric fields are derived. The numerical results analyze the influence of size parameter, relative refractive index, and rotating dimensionless parameter on the CPNJ. The curved effect of the photonic nanojet is emphasized, which can be used for off-axis photonic nanojet (PNJ) generation by adjusting the angular velocity of the dielectric cylinder.
Article
Mathematics
Gerassimos Manoussakis
Summary: In this article, a solution method for a problem formulated by a partial differential equation and Dirichlet boundary condition is developed based on the behavior of spherical gravity fields. The solution is represented using a series of spherical harmonics and a rigorous asymptotic analysis is conducted considering eccentricity. By determining the coefficients in the expansion, the gravity force for a non-rotating spheroid with low eccentricity is obtained. The limiting case of this series represents the gravity force of a non-rotating sphere.
Article
Mechanics
J. Sanchez Umbria, M. Net
Summary: The aim of this study is to investigate the three-dimensional torsional dynamics of thermal convection in rotating spherical fluids at very low Prandtl numbers through numerical simulations. The study shows that the breaking of axisymmetry at a secondary Hopf bifurcation leads to a quasiperiodic motion that propagates energy in both latitude and longitude, resulting in a meandering path of kinetic energy concentrated on the surface. Different stable states of convection with various symmetries have been identified, all retaining the torsional motion of the basic velocity field, with attention paid to their dependence on Rayleigh number and other factors.
Article
Geosciences, Multidisciplinary
Rishav Goyal, Martin Jucker, Alex Sen Gupta, Harry H. Hendon, Matthew H. England
Summary: The zonal wave 3 circulation pattern in the Southern Hemisphere is primarily driven by tropical convection, rather than extratropical factors. Changes in tropical deep convection play a key role in controlling the zonal wave 3 pattern, with implications for southern high-latitude climate, ocean circulation, and sea ice.
Article
Astronomy & Astrophysics
He Jia, Christopher J. White, Eliot Quataert, Sean M. Ressler
Summary: We study the observational signatures of magnetically arrested black hole accretion with non-rotating inflow onto a rotating black hole. The results of our simulations show that the mm intensity images, polarization images, and synchrotron emission spectra are very similar among different simulations when processed with the same electron temperature model. The orientation of the mm synchrotron polarization is particularly insensitive to the initial magnetic field orientation, electron temperature model, and rotation of the inflowing plasma. The largest difference among the simulations with different initial rotation and magnetic tilt is in the strength and stability of the jet.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Mechanics
Stanislav Subbotin, Mariya Shiryaeva
Summary: Experimental investigation on fluid flow excited by a core oscillating in a rotating spherical cavity shows that oscillations set by an external inertial field causes non-axisymmetric inertial waves and shear layers to form in the fluid bulk. Different inertial flow regimes arise depending on the oscillation frequency and sign, with each regime corresponding to a steady zonal flow. The flow structure consists of nested liquid geostrophic cylinders, with intense zonal flow occurring when inertial waves are superposed and global vortex structures are resonantly excited.
Article
Chemistry, Physical
Lorenz S. Cederbaum
Summary: Studying the impact of rotating the cavity on polaritons reveals an increase in the number of polaritons and the induction of new polaritons that strongly depend on angular velocity and axis of rotation. This rotation-induced modification in the structure of original polaritons can significantly alter the number and dimensionality of light-induced conical intersections in molecules, thereby impacting their quantum dynamics. General consequences of these findings are discussed.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
