Large-scale anisotropy in stably stratified rotating flows
We present results from direct numerical simulations of the Boussinesq equations in the presence of rotation and/or stratification, both in the vertical direction. The runs are forced isotropically and randomly at small scales and have spatial resolutions of up to 10243 grid points and Reynolds numb...
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| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_15393755_v90_n2_p_Marino |
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todo:paper_15393755_v90_n2_p_Marino2023-10-03T16:22:49Z Large-scale anisotropy in stably stratified rotating flows Marino, R. Mininni, P.D. Rosenberg, D.L. Pouquet, A. Fluid dynamics Kinetic energy Kinetics Reynolds number Boussinesq equations Isotropic energy Large scale anisotropy Power-law behavior Rotating turbulence Scale separation Spatial resolution Vertical direction Anisotropy solution and solubility anisotropy computer simulation energy transfer Fourier analysis kinetics rotation solution and solubility theoretical model Anisotropy Computer Simulation Energy Transfer Fourier Analysis Kinetics Models, Theoretical Rotation Solutions We present results from direct numerical simulations of the Boussinesq equations in the presence of rotation and/or stratification, both in the vertical direction. The runs are forced isotropically and randomly at small scales and have spatial resolutions of up to 10243 grid points and Reynolds numbers of ≈1000. We first show that solutions with negative energy flux and inverse cascades develop in rotating turbulence, whether or not stratification is present. However, the purely stratified case is characterized instead by an early-time, highly anisotropic transfer to large scales with almost zero net isotropic energy flux. This is consistent with previous studies that observed the development of vertically sheared horizontal winds, although only at substantially later times. However, and unlike previous works, when sufficient scale separation is allowed between the forcing scale and the domain size, the kinetic energy displays a perpendicular (horizontal) spectrum with power-law behavior compatible with ∼k-5/3, including in the absence of rotation. In this latter purely stratified case, such a spectrum is the result of a direct cascade of the energy contained in the large-scale horizontal wind, as is evidenced by a strong positive flux of energy in the parallel direction at all scales including the largest resolved scales. © 2014 American Physical Society. Fil:Mininni, P.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_15393755_v90_n2_p_Marino |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Fluid dynamics Kinetic energy Kinetics Reynolds number Boussinesq equations Isotropic energy Large scale anisotropy Power-law behavior Rotating turbulence Scale separation Spatial resolution Vertical direction Anisotropy solution and solubility anisotropy computer simulation energy transfer Fourier analysis kinetics rotation solution and solubility theoretical model Anisotropy Computer Simulation Energy Transfer Fourier Analysis Kinetics Models, Theoretical Rotation Solutions |
| spellingShingle |
Fluid dynamics Kinetic energy Kinetics Reynolds number Boussinesq equations Isotropic energy Large scale anisotropy Power-law behavior Rotating turbulence Scale separation Spatial resolution Vertical direction Anisotropy solution and solubility anisotropy computer simulation energy transfer Fourier analysis kinetics rotation solution and solubility theoretical model Anisotropy Computer Simulation Energy Transfer Fourier Analysis Kinetics Models, Theoretical Rotation Solutions Marino, R. Mininni, P.D. Rosenberg, D.L. Pouquet, A. Large-scale anisotropy in stably stratified rotating flows |
| topic_facet |
Fluid dynamics Kinetic energy Kinetics Reynolds number Boussinesq equations Isotropic energy Large scale anisotropy Power-law behavior Rotating turbulence Scale separation Spatial resolution Vertical direction Anisotropy solution and solubility anisotropy computer simulation energy transfer Fourier analysis kinetics rotation solution and solubility theoretical model Anisotropy Computer Simulation Energy Transfer Fourier Analysis Kinetics Models, Theoretical Rotation Solutions |
| description |
We present results from direct numerical simulations of the Boussinesq equations in the presence of rotation and/or stratification, both in the vertical direction. The runs are forced isotropically and randomly at small scales and have spatial resolutions of up to 10243 grid points and Reynolds numbers of ≈1000. We first show that solutions with negative energy flux and inverse cascades develop in rotating turbulence, whether or not stratification is present. However, the purely stratified case is characterized instead by an early-time, highly anisotropic transfer to large scales with almost zero net isotropic energy flux. This is consistent with previous studies that observed the development of vertically sheared horizontal winds, although only at substantially later times. However, and unlike previous works, when sufficient scale separation is allowed between the forcing scale and the domain size, the kinetic energy displays a perpendicular (horizontal) spectrum with power-law behavior compatible with ∼k-5/3, including in the absence of rotation. In this latter purely stratified case, such a spectrum is the result of a direct cascade of the energy contained in the large-scale horizontal wind, as is evidenced by a strong positive flux of energy in the parallel direction at all scales including the largest resolved scales. © 2014 American Physical Society. |
| format |
JOUR |
| author |
Marino, R. Mininni, P.D. Rosenberg, D.L. Pouquet, A. |
| author_facet |
Marino, R. Mininni, P.D. Rosenberg, D.L. Pouquet, A. |
| author_sort |
Marino, R. |
| title |
Large-scale anisotropy in stably stratified rotating flows |
| title_short |
Large-scale anisotropy in stably stratified rotating flows |
| title_full |
Large-scale anisotropy in stably stratified rotating flows |
| title_fullStr |
Large-scale anisotropy in stably stratified rotating flows |
| title_full_unstemmed |
Large-scale anisotropy in stably stratified rotating flows |
| title_sort |
large-scale anisotropy in stably stratified rotating flows |
| url |
http://hdl.handle.net/20.500.12110/paper_15393755_v90_n2_p_Marino |
| work_keys_str_mv |
AT marinor largescaleanisotropyinstablystratifiedrotatingflows AT mininnipd largescaleanisotropyinstablystratifiedrotatingflows AT rosenbergdl largescaleanisotropyinstablystratifiedrotatingflows AT pouqueta largescaleanisotropyinstablystratifiedrotatingflows |
| _version_ |
1807322181544181760 |