Nonmodal energetics of electromagnetic drift waves

Camargo, Suzana J.; Tippett, Michael K.; Caldas, Iberê L.

doi:10.1063/1.874134

Cited by 8 publications

(4 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In general, nonnormal M may give rise to strong amplification of applied perturbations even when the plasma is stable. [46][47][48][49][50] It is also responsible for the fact that the eigenmodes of the resistive MHD equations do not converge to those of the ideal MHD system as the resistivity goes to zero. This is sometimes referred to as the Alfvén paradox.…”

Section: Iia General Formulationmentioning

confidence: 99%

Models for Sub-Alfvénic Magnetodynamics of Fusion Plasmas

Waelbroeck

2011

Fusion Science and Technology

View full text Add to dashboard Cite

Section: Iia General Formulationmentioning

confidence: 99%

Models for Sub-Alfvénic Magnetodynamics of Fusion Plasmas

Waelbroeck

2011

Fusion Science and Technology

View full text Add to dashboard Cite

“…The causes and the time rates of the cross-field transport have been one of the main themes in the study of plasma confinement in tokamaks [3]. Various theoretical models have been devised to identify the underlying plasma turbulence mechanisms thought to cause this anomalous transport [2,4,5]. Plasma turbulence often displays a broad fluctuation spectra with maxima at the longest measured scales (small wave vectors and high frequencies) [1].…”

Section: Introductionmentioning

confidence: 99%

Turbulence Induced Transport in Tokamaks

Caldas¹,

Marcus²,

Batista³

et al. 2006

AIP Conference Proceedings

View full text Add to dashboard Cite

This report is concerned with plasma edge turbulence and its relation to anomalous particle transport in tokamaks. First, experimental evidence of turbulence driven particle transport and measurements of the gradients of the equilibrium profiles in the Brazilian tokamaks TBR and TCABR are presented. Next, diffusion in a two drift-wave system is discussed. In this nonintegrable system, particle transport is associated with the onset of chaotic orbits. Finally, numerical evidence suggesting that a nonlinear three-mode interaction could contribute to the intermittent plasma fluctuations observed in tokamaks is presented.

show abstract

“…The reason is because in many fluid flows of practical interest, including Poiseuille flow ͑pipe flow͒ and Couette flow, the eigenfunctions of the linearized and Fourier transformed equations of motion are not all mutually orthogonal. [11][12][13][14][15][16][17][18][19][20][21] The idea that systems with stable eigenvalues may possess transient solutions that initially grow with time is not new. This burgeoning field has led to a more complete understanding of instabilities and of the transition to turbulence in wall bounded shear flows that cannot be explained by the traditional normal mode analysis.…”

Section: Introductionmentioning

confidence: 99%

Transient growth in stable linearized Vlasov–Maxwell plasmas

Podesta

2010

Physics of Plasmas

View full text Add to dashboard Cite

Large amplitude transient growth of kinetic scale perturbations in stable collisionless magnetized plasmas has recently been demonstrated using a linearized Landau fluid model. Initial perturbations with lengthscales of the order of the ion gyroradius were shown to have transient timescales that in some cases were long compared to the ion gyroperiod, ⍀ i t ӷ 1. Moreover, it was suggested that such perturbations are not rare but instead form a large class within the set of all possible initial conditions. For collisionless plasmas, the Vlasov-Maxwell equations provide a more complete description of kinetic physics and the existence of transient growth of solutions for the linearized Vlasov-Maxwell system is an interesting question. The existence of transient growth of solutions is demonstrated here for a special case of the Vlasov-Maxwell equations, namely, the one dimensional Vlasov-Poisson system. The analysis is different from the standard approach of nonmodal analysis since the initial value problem is described by a Volterra integral equation of the second kind, reflecting the fact that the time evolution of the system depends on the memory of the state from time zero through time t. For the case of a thermal equilibrium plasma, it is shown how initial conditions may be constructed to obtain solutions that grow linearly in time; the duration of this growth is the time required for a thermal electron to traverse the wavelength of the initial perturbation, a timescale that can last for many plasma periods 2 / pe , thus demonstrating the existence of transient growth of solutions for the linearized Vlasov-Poisson system. The results suggest that the phenomenon of transient growth may be a common feature of the linearized Vlasov-Maxwell system as well as for Landau fluid models.

show abstract

Nonmodal energetics of electromagnetic drift waves

Cited by 8 publications

References 31 publications

Models for Sub-Alfvénic Magnetodynamics of Fusion Plasmas

Models for Sub-Alfvénic Magnetodynamics of Fusion Plasmas

Turbulence Induced Transport in Tokamaks

Transient growth in stable linearized Vlasov–Maxwell plasmas

Contact Info

Product

Resources

About