Interactive desktop analysis of high resolution simulations: application to turbulent plume dynamics and current sheet formation

Clyne, D. John; Mininni, Pablo D.; Norton, Alan; Rast, Mark

doi:10.1088/1367-2630/9/8/301

Cited by 279 publications

(201 citation statements)

References 36 publications

Supporting

Mentioning

198

Contrasting

Unclassified

Order By: Relevance

“…The slab thickness in the x (depth) direction is 0.04 times the box size. All renderings were made using the using the VAPOR visualization system [47].…”

Section: B Specific Numerical Proceduresmentioning

confidence: 99%

Evidence for Bolgiano-Obukhov scaling in rotating stratified turbulence using high-resolution direct numerical simulations

et al. 2015

View full text Add to dashboard Cite

We report results on rotating stratified turbulence in the absence of forcing, with large-scale isotropic initial conditions, using direct numerical simulations computed on grids of up to 4096 3 points. The Reynolds and Froude numbers are respectively equal to Re = 5.4×10 4 and F r = 0.0242. The ratio of the Brunt-Väisälä to the inertial wave frequency, N/f , is taken to be equal to 4.95, a choice appropriate to model the dynamics of the southern abyssal ocean at mid latitudes. This gives a global buoyancy Reynolds number RB = ReF r 2 = 32, a value sufficient for some isotropy to be recovered in the small scales beyond the Ozmidov scale, but still moderate enough that the intermediate scales where waves are prevalent are well resolved. We concentrate on the largescale dynamics, for which we find a spectrum compatible with the Bolgiano-Obukhov scaling, and confirm that the Froude number based on a typical vertical length scale is of order unity, with strong gradients in the vertical. Two characteristic scales emerge from this computation, and are identified from sharp variations in the spectral distribution of either total energy or helicity. A spectral break is also observed at a scale at which the partition of energy between the kinetic and potential modes changes abruptly, and beyond which a Kolmogorov-like spectrum recovers. Large slanted layers are ubiquitous in the flow in the velocity and temperature fields, with local overturning events indicated by small Richardson numbers, and a small large-scale enhancement of energy directly attributable to the effect of rotation is also observed.

show abstract

“…The slab thickness in the x (depth) direction is 0.04 times the box size. All renderings were made using the using the VAPOR visualization system [47].…”

Section: B Specific Numerical Proceduresmentioning

confidence: 99%

Evidence for Bolgiano-Obukhov scaling in rotating stratified turbulence using high-resolution direct numerical simulations

et al. 2015

View full text Add to dashboard Cite

show abstract

“…thanks Hao Liu and Masateru Maeda for useful comments. Imagery in Fig.2C was produced using VAPOR, a product of the Computational Information Systems Laboratory at the National Center for Atmospheric Research (Clyne et al, 2007).…”

Section: Acknowledgementsmentioning

confidence: 99%

Force balance in the take-off of a pierid butterfly: relative importance and timing of leg impulsion and aerodynamic forces

Bimbard¹,

Kolomenskiy²,

Bouteleux³

et al. 2013

Journal of Experimental Biology

View full text Add to dashboard Cite

SUMMARYUp to now, the take-off stage has remained an elusive phase of insect flight that was relatively poorly explored compared with other maneuvers. An overall assessment of the different mechanisms involved in force production during take-off has never been explored. Focusing on the first downstroke, we have addressed this problem from a force balance perspective in butterflies taking off from the ground. In order to determine whether the sole aerodynamic wing force could explain the observed motion of the insect, we have firstly compared a simple analytical model of the wing force with the acceleration of the insect's center of mass estimated from video tracking of the wing and body motions. Secondly, wing kinematics were also used for numerical simulations of the aerodynamic flow field. Similar wing aerodynamic forces were obtained by the two methods. However, neither are sufficient, nor is the inclusion of the ground effect, to predict faithfully the body acceleration. We have to resort to the leg forces to obtain a model that best fits the data. We show that the median and hind legs display an active extension responsible for the initiation of the upward motion of the insect's body, occurring before the onset of the wing downstroke. We estimate that legs generate, at various times, an upward force that can be much larger than all other forces applied to the insect's body. The relative timing of leg and wing forces explains the large variability of trajectories observed during the maneuvers. Supplementary material available online at

show abstract

“…1. The image is generated with the VAPOR 3D visualisation package (Clyne et al 2007). Stream lines (red curves) reveal a large amount of vortex motions in the upper photosphere.…”

Section: Simulationsmentioning

confidence: 99%

Vorticity in the solar photosphere

Shelyag

Keys

Mathioudakis

et al. 2010

A&A

121

119

View full text Add to dashboard Cite

Aims. We use magnetic and non-magnetic 3D numerical simulations of solar granulation and G-band radiative diagnostics from the resulting models to analyse the generation of small-scale vortex motions in the solar photosphere. Methods. Radiative MHD simulations of magnetoconvection are used to produce photospheric models. Our starting point is a nonmagnetic model of solar convection, where we introduce a uniform magnetic field and follow the evolution of the field in the simulated photosphere. We find two different types of photospheric vortices, and provide a link between the vorticity generation and the presence of the intergranular magnetic field. A detailed analysis of the vorticity equation, combined with the G-band radiative diagnostics, allows us to identify the sources and observational signatures of photospheric vorticity in the simulated photosphere. Results. Two different types of photospheric vorticity, magnetic and non-magnetic, are generated in the domain. Non-magnetic vortices are generated by the baroclinic motions of the plasma in the photosphere, while magnetic vortices are produced by the magnetic tension in the intergranular magnetic flux concentrations. The two types of vortices have different shapes. We find that the vorticity is generated more efficiently in the magnetised model. Simulated G-band images show a direct connection between magnetic vortices and rotary motions of photospheric bright points, and suggest that there may be a connection between the magnetic bright point rotation and small-scale swirl motions observed higher in the atmosphere.

show abstract

Interactive desktop analysis of high resolution simulations: application to turbulent plume dynamics and current sheet formation

Cited by 279 publications

References 36 publications

Evidence for Bolgiano-Obukhov scaling in rotating stratified turbulence using high-resolution direct numerical simulations

Evidence for Bolgiano-Obukhov scaling in rotating stratified turbulence using high-resolution direct numerical simulations

Force balance in the take-off of a pierid butterfly: relative importance and timing of leg impulsion and aerodynamic forces

Vorticity in the solar photosphere

Contact Info

Product

Resources

About