The turbulent response to tidal and libration forcing

In conjunction with thermo-solutal convection, the turbulence generated in planetary liquid cores may be due to the role of boundary forcing through geophysically relevant mechanisms such as precession, libration and tidal forcing (Le Bars et al. 2015). In this paper, we discuss laboratory equatorial velocity measurements and selected high-resolution numerical simulations to show the generation of developed turbulence driven by longitudinal libration or tidal forcing. In both cases, the transition to saturated turbulence is driven by an elliptical instability that excites inertial modes of the system. We find striking similarities in both the transition to bulk turbulence and the enhanced zonal flow hinting at a generic fluid response independent of the forcing mechanism. We finally discuss the relevance of this work to the planetary regime and possible directions for future investigations.

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Shear Driven Turbulence and Coherent Structures in Solar Surface Simulations

Proceedings of the International Astronomical Union ◽

10.1017/s174392130802348x ◽

2008 ◽

Vol 4 (S252) ◽

pp. 451-461 ◽

Cited By ~ 1

Author(s):

F. Kupka

Keyword(s):

High Resolution ◽

Boundary Conditions ◽

Numerical Simulations ◽

Observational Data ◽

Coherent Structures ◽

Solar Surface ◽

Large Set ◽

Mode Excitation

AbstractNumerical simulations of convection near the solar surface are now advanced enough to reproduce both a large set of observational data and provide tests for convection models. We discuss the role of coherent structures in models of solar p-mode excitation, for which the analysis of numerical simulations has provided key inputs in the modelling. The robustness of these simulations is shown by a comparison illustrating the influence of boundary conditions on ensemble averaged quantities. In a concluding example advanced high resolution simulations are shown to resolve the onset of shear driven turbulence generated by up- and downflow structures.

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Gamma-ray burst jet dynamics and their interaction with the progenitor star

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2006.1980 ◽

2007 ◽

Vol 365 (1854) ◽

pp. 1141-1149 ◽

Cited By ~ 9

Author(s):

Davide Lazzati ◽

Brian J Morsony ◽

Mitchell C Begelman

Keyword(s):

High Resolution ◽

Numerical Simulations ◽

Gamma Ray ◽

Gamma Ray Bursts ◽

Stellar Surface ◽

Reasonable Doubt ◽

Stellar Core ◽

Relativistic Flow ◽

Supernova Explosions

The association of at least some long gamma-ray bursts with type Ic supernova explosions has been established beyond reasonable doubt. Theoretically, the challenge is to explain the presence of a light hyper-relativistic flow propagating through a massive stellar core without losing those properties. We discuss the role of the jet–star interaction in shaping the properties of the outflow emerging on the surface of the star. We show that the nature of the inner engine is hidden from the observer for most of the evolution, well beyond the time of the jet breakout on the stellar surface. The discussion is based on analytical considerations as well as high resolution numerical simulations. Finally, the observational consequences of the scenario are addressed in light of the present capabilities.

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Role of barriers in the airborne spread of virus-containing droplets: A study based on high-resolution direct numerical simulations

Physics of Fluids ◽

10.1063/5.0072840 ◽

2022 ◽

Vol 34 (1) ◽

pp. 015104

Author(s):

M. Cavaiola ◽

S. Olivieri ◽

J. Guerrero ◽

A. Mazzino ◽

M. E. Rosti

Keyword(s):

High Resolution ◽

Numerical Simulations ◽

Direct Numerical Simulations

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Supplemental Material for High Resolution Examination of the Role of Sleep Disturbance in Predicting Functioning and Psychotic Symptoms in Schizophrenia: A Novel Experience Sampling Study

Journal of Abnormal Psychology ◽

10.1037/abn0000180.supp ◽

2016 ◽

Keyword(s):

High Resolution ◽

Sleep Disturbance ◽

Experience Sampling ◽

Psychotic Symptoms

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Quantitative accuracy of serotonergic neurotrans-mission imaging with high-resolution 123I SPECT

Nuklearmedizin ◽

10.1055/s-0038-1623914 ◽

2004 ◽

Vol 43 (06) ◽

pp. 185-189 ◽

Cited By ~ 4

Author(s):

J. T. Kuikka

Keyword(s):

High Resolution ◽

Scatter Correction ◽

Region Of Interest ◽

Binding Potential ◽

Partial Volume ◽

Therapeutic Drugs ◽

Quantitative Accuracy ◽

Critical Error ◽

Statistical Noise

Summary Aim: Serotonin transporter (SERT) imaging can be used to study the role of regional abnormalities of neurotransmitter release in various mental disorders and to study the mechanism of action of therapeutic drugs or drugs’ abuse. We examine the quantitative accuracy and reproducibility that can be achieved with high-resolution SPECT of serotonergic neurotransmission. Method: Binding potential (BP) of 123I labeled tracer specific for midbrain SERT was assessed in 20 healthy persons. The effects of scatter, attenuation, partial volume, mis-registration and statistical noise were estimated using phantom and human studies. Results: Without any correction, BP was underestimated by 73%. The partial volume error was the major component in this underestimation whereas the most critical error for the reproducibility was misplacement of region of interest (ROI). Conclusion: The proper ROI registration, the use of the multiple head gamma camera with transmission based scatter correction introduce more relevant results. However, due to the small dimensions of the midbrain SERT structures and poor spatial resolution of SPECT, the improvement without the partial volume correction is not great enough to restore the estimate of BP to that of the true one.

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