The Turbulent Cascade at 1 AU: Energy Transfer and the Third‐Order Scaling for MHD

2008 ◽  
Vol 679 (2) ◽  
pp. 1644-1660 ◽  
Author(s):  
Benjamin T. MacBride ◽  
Charles W. Smith ◽  
Miriam A. Forman
Keyword(s):  
Energy Transfer ◽  
Third Order ◽  
The Third ◽  
Turbulent Cascade

Comparing turbulence in a Kelvin-Helmholtz instability region across the terrestrial magnetopause

2021 ◽  
Author(s):  
Paulina Quijia ◽  
Federico Fraternale ◽  
Julia E Stawarz ◽  
Christian L Vásconez ◽  
Silvia Perri ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Instability Region ◽  
Order Moment ◽  
Energy Transfer Rate ◽  
Helmholtz Instability ◽  
Third Order ◽  
The Third ◽  
Magnetospheric Multiscale ◽  
Magnetospheric Boundary ◽  
Turbulent Cascade

Abstract The properties of turbulence observed within the plasma originating from the magnetosheath and the magnetospheric boundary layer, which have been entrained within vortices driven by the Kelvin-Helmholtz Instability (KHI), are compared. The goal of such a study is to determine similarities and differences between the two different regions. In particular, we study spectra, intermittency and the third-order moment scaling, as well as the distribution of a local energy transfer rate proxy. The analysis is performed using the Magnetospheric Multiscale (MMS) data from a single satellite that crosses longitudinally the KHI. Two sets of regions, one set containing predominantly magnetosheath plasma and the other containing predominantly magnetospheric plasma, are analyzed separately, thus allowing us to explore turbulence properties in two portions of very different plasma samples. Results show that the turbulence in the two regions is different, with the boundary layer plasma including current structures that may not be originated by the turbulent cascade. This suggests that the observed turbulence is affected by the KHI.

scholarly journals Impact of Switchbacks on Turbulent Cascade and Energy Transfer Rate in the Inner Heliosphere

2021 ◽  
Vol 922 (1) ◽  
pp. L11
Author(s):  
Carlos S. Hernández ◽  
Luca Sorriso-Valvo ◽  
Riddhi Bandyopadhyay ◽  
Alexandros Chasapis ◽  
Christian L. Vásconez ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Transfer Rate ◽  
Positive Energy ◽  
Magnetic Fluctuations ◽  
Energy Transfer Rate ◽  
Third Order ◽  
Additional Energy ◽  
The Magnetic Field ◽  
Turbulent Cascade ◽  
Inner Heliosphere

Abstract Recent Parker Solar Probe (PSP) observations of inner heliospheric plasma have shown an abundant presence of Alfvénic polarity reversal of the magnetic field, known as “switchbacks.” While their origin is still debated, their role in driving the solar wind turbulence has been suggested through analysis of the spectral properties of magnetic fluctuations. Here, we provide a complementary assessment of their role in the turbulent cascade. The validation of the third-order linear scaling of velocity and magnetic fluctuations in intervals characterized by a high occurrence of switchbacks suggests that, irrespective of their local or remote origin, these structures are actively embedded in the turbulent cascade, at least at the radial distances sampled by PSP during its first perihelion. The stronger positive energy transfer rate observed in periods with a predominance of switchbacks indicates that they act as a mechanism injecting additional energy in the turbulence cascade.

scholarly journals Nonlinear Evolution of a Steep, Focusing Wave Group in Deep Water Simulated With oceanwave3d

2019 ◽  
Vol 142 (2) ◽  
Author(s):  
Dylan Barratt ◽  
Harry B. Bingham ◽  
Thomas A. A. Adcock
Keyword(s):  
Energy Transfer ◽  
Deep Water ◽  
Nonlinear Evolution ◽  
Initial Conditions ◽  
Amplitude Spectrum ◽  
Wave Group ◽  
Third Order ◽  
The Third ◽  
Nonlinear Potential ◽  
Wave Event

Abstract Steep, focusing waves can experience fast and local nonlinear evolution of the spectrum due to wave–wave interactions resulting in energy transfer to both higher and lower wavenumber components. The shape and kinematics of a steep wave may, thus, differ substantially from the predictions of linear theory. We have investigated the role of nonlinear interactions on group shape for a steep, narrow-banded, directionally spread wave group focusing in deep water using the fully nonlinear potential flow solver, oceanwave3d. Exact second-order correction of the initial conditions has been implemented together with a novel third-order approximate correction based on a Stokes-type formulation for surface elevation combined with a scaling argument for the third-order velocity potential. Four-phase separation reveals that the third-order scheme provides a good estimate for the third-order superharmonics. A quantitative assessment of numerical error has also been performed for the spatial and temporal discretization, including energy conservation, a reversibility check, and validation against previous simulations performed with a higher-order spectral (HOS) code. The initially narrow-banded amplitude spectrum exhibits the formation of “sidelobes” at angles of approximately ±35deg to the spectral peak during the simulated extreme wave event, occurring in approximately ten wave periods, with a preferential energy transfer to high-wavenumber components. The directional energy transfer is attributed to resonant third-order interactions with a discussion of the engineering implications.

scholarly journals Nonlinear Evolution of a Steep, Focusing Wave Group in Deep Water Simulated With OceanWave3D

2019 ◽  
Author(s):  
Dylan Barratt ◽  
Harry B. Bingham ◽  
Thomas A. A. Adcock
Keyword(s):  
Energy Transfer ◽  
Deep Water ◽  
Nonlinear Evolution ◽  
Initial Conditions ◽  
Amplitude Spectrum ◽  
Wave Group ◽  
Third Order ◽  
The Third ◽  
Nonlinear Potential ◽  
Wave Event

Abstract Steep, focusing waves can experience fast and local nonlinear evolution of the spectrum due to wave-wave interactions resulting in energy transfer to both higher and lower wavenumber components. The shape and kinematics of a steep wave may, thus, differ substantially from the predictions of linear theory. We have investigated the role of nonlinear interactions on group-shape for a steep, narrow-banded, directionally-spread wave group focusing in deep water using the fully-nonlinear potential flow solver, OceanWave3D. Exact second-order correction of the initial conditions has been implemented together with a novel third-order approximate correction based on a Stokes-type formulation for surface elevation combined with a scaling-argument for the third-order velocity potential. Four-phase separation reveals that the third-order scheme provides a good estimate for the third-order superharmonics. A quantitative assessment of numerical error has also been performed for the spatial and temporal discretization, including energy conservation, a reversibility check and validation against previous simulations performed with a higher-order spectral (HOS) code. The initially narrow-banded amplitude spectrum exhibits the formation of sidelobes at angles of approximately ±35° to the spectral peak during the simulated extreme wave event, occurring in approximately 10 wave periods, with a preferential energy transfer to high-wavenumber components. The directional energy transfer is attributed to resonant third-order interactions with a discussion of the engineering implications.

Studies in energy transfer I. The combination of iodine atoms

1953 ◽  
Vol 217 (1129) ◽  
pp. 271-279 ◽  
Keyword(s):  
Energy Transfer ◽  
Intermolecular Force ◽  
Third Body ◽  
Reaction Cell ◽  
Critical Temperatures ◽  
Third Order ◽  
First Order ◽  
The Third ◽  
Boiling Points ◽  
Factors Influencing

An experimental study has been made of the velocity of combination of iodine atoms in the presence of a number of added gases in order to investigate the factors influencing energy transfer. The reaction cell, containing iodine at a pressure of 0.097 mm Hg and a known pressure of third body, is irradiated with a flash from a discharge tube. The concentration of iodine atoms as recombination proceeds is determined by measuring the light absorption of the system with a photomultiplier tube. The reaction is second order with respect to the concentration of iodine atoms, and first order with respect to the third body. The third-order rate constants vary from 0.97 x 10 -32 mol. -2 cm 6 s -1 when helium is added to 224 x 10 -32 mol -2 cm 6 s -1 for mesitylene. The velocity of combination at 127° C has been found to be approximately 0.4 time the velocity at 20° C for six different additives. This factor seems to be independent of the nature of the additive. The efficiencies of the different additives is primarily determined by the magnitudes of their intermolecular force fields, which are reflected in their boiling-points and critical temperatures.

Probe size and 5th-order aberration

1987 ◽  
Vol 45 ◽  
pp. 134-135 ◽  
Author(s):  
Zhifeng Shao
Keyword(s):  
Electron Probe ◽  
Spherical Aberration ◽  
Wave Length ◽  
Cylindrical Symmetry ◽  
Electron Wave ◽  
Third Order ◽  
The Third ◽  
Probe Radius ◽  
Small Probe ◽  
Probe Size

A small electron probe has many applications in many fields and in the case of the STEM, the probe size essentially determines the ultimate resolution. However, there are many difficulties in obtaining a very small probe.Spherical aberration is one of them and all existing probe forming systems have non-zero spherical aberration. The ultimate probe radius is given byδ = 0.43Csl/4ƛ3/4where ƛ is the electron wave length and it is apparent that δ decreases only slowly with decreasing Cs. Scherzer pointed out that the third order aberration coefficient always has the same sign regardless of the field distribution, provided only that the fields have cylindrical symmetry, are independent of time and no space charge is present. To overcome this problem, he proposed a corrector consisting of octupoles and quadrupoles.

Children’s Recall of Approximations to English

1973 ◽  
Vol 16 (2) ◽  
pp. 201-212 ◽  
Author(s):  
Elizabeth Carrow ◽  
Michael Mauldin
Keyword(s):  
Language Development ◽  
Fourth Order ◽  
Third Order ◽  
Memory Processes ◽  
The Third ◽  
General Index ◽  
General Linguistic

As a general index of language development, the recall of first through fourth order approximations to English was examined in four, five, six, and seven year olds and adults. Data suggested that recall improved with age, and increases in approximation to English were accompanied by increases in recall for six and seven year olds and adults. Recall improved for four and five year olds through the third order but declined at the fourth. The latter finding was attributed to deficits in semantic structures and memory processes in four and five year olds. The former finding was interpreted as an index of the development of general linguistic processes.

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