Self-similar state of a weakly turbulent plasma

The models of Vekshtein, Ryutov & Sagdeev (VRS), describing a marginally stable turbulent plasma sustaining an electric current, are shown to be incomplete by their neglect of the equations determining the spectral densities of the driving modes. An exhaustive study of these models including a detailed determination of the frequencies, spectral densities and turbulent energy densities, shows that, strictly speaking, there exists no self-similar turbulent state (SSTS). However, an approximate SSTS can be constructed, based on the finding that the tail of the spectral densities behaves self-similarly.

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Anomalous transport coefficients in a magnetized turbulent plasma

Journal of Plasma Physics ◽

10.1017/s0022377800000210 ◽

1982 ◽

Vol 28 (2) ◽

pp. 193-214 ◽

Cited By ~ 1

Author(s):

Qiu Xiaoming ◽

R. Balescu

Keyword(s):

Transport Coefficients ◽

Collision Operator ◽

Turbulent Plasma ◽

Anomalous Transport ◽

Weak Turbulence ◽

Dissipative Effects ◽

Dependent Transport ◽

Two Fluid ◽

Two Fluid Plasma

In this paper we generalize the formalism developed by Balescu and Paiva-Veretennicoff, valid for any kind of weak turbulence, for the determination of all the transport coefficients of an unmagnetized turbulent plasma, to the case of a magnetized one, and suggest a technique to avoid finding the inverse of the turbulent collision operator. The implicit plasmadynamical equations of a two-fluid plasma are presented by means of plasmadynamical variables. The anomalous transport coefficients appear in their natural places in these equations. It is shown that the necessary number of transport coefficients for describing macroscopically the magnetized turbulent plasma does not exceed the number for the unmagnetized one. The typical turbulent and gyromotion terms, representing dissipative effects peculiar to the magnetized system, which contribute to the frequency-dependent transport coefficients are clearly exhibited.

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Experimental determination of spectral densities in quasi-one-dimensional electron systems

Physica B Condensed Matter ◽

10.1016/s0921-4526(98)00093-3 ◽

1998 ◽

Vol 249-251 ◽

pp. 175-179

Author(s):

B. Kardynal ◽

C.H.W. Barnes ◽

E.H. Linfield ◽

D.A. Ritchie ◽

J.T. Nicholls ◽

...

Keyword(s):

Experimental Determination ◽

Electron Systems ◽

Dimensional Electron ◽

Spectral Densities ◽

One Dimensional

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The evolution of turbulent bursts: the b—ε model

European Journal of Applied Mathematics ◽

10.1017/s0956792500001601 ◽

1994 ◽

Vol 5 (4) ◽

pp. 537-557 ◽

Cited By ~ 5

Author(s):

M. Bertsch ◽

R. Dal Passo ◽

R. Kersner

Keyword(s):

Partial Differential Equations ◽

Energy Dissipation ◽

Energy Density ◽

Differential Equations ◽

Dissipation Rate ◽

Turbulent Energy ◽

Energy Dissipation Rate ◽

Self Similar ◽

The universal splitting property. II

Journal of Symbolic Logic ◽

10.2307/2274097 ◽

1984 ◽

Vol 49 (1) ◽

pp. 137-150 ◽

Cited By ~ 11

Author(s):

M. Lerman ◽

J. B. Remmel

Keyword(s):

Turing Degree ◽

Splitting Theorem ◽

Splitting Property ◽

Exhaustive Study

We say that a pair of r.e. sets B and C split an r.e. set A if B ∩ C = ∅ and B ∪ C = A. Friedberg [F] was the first to study the degrees of splittings of r.e. sets. He showed that every nonrecursive r.e. set A has a splitting into nonrecursive sets. Generalizations and strengthenings of Friedberg's result were obtained by Sacks [Sa2], Owings [O], and Morley and Soare [MS].The question which motivated both [LR] and this paper is the determination of possible degrees of splittings of A. It is easy to see that if B and C split A, then both B and C are Turing reducible to A (written B ≤TA and C ≤TA). The Sacks splitting theorem [Sa2] is a result in this direction, as are results by Lachlan and Ladner on mitotic and nonmitotic sets. Call an r.e. set A mitotic if there is a splitting B and C of A such that both B and C have the same Turing degree as A; A is nonmitotic otherwise. Lachlan [Lac] showed that nonmitotic sets exist, and Ladner [Lad1], [Lad2] carried out an exhaustive study of the degrees of mitotic sets.The Sacks splitting theorem [Sa2] shows that if A is r.e. and nonrecursive, then there are r.e. sets B and C splitting A such that B <TA and C <TA. Since B is r.e. and nonrecursive, we can now split B and continue in this manner to produce infinitely many r.e. degrees below the degree of A which are degrees of sets forming part of a splitting of A. We say that an r.e. set A has the universal splitting property (USP) if for any r.e. set D ≤T A, there is a splitting B and C of A such that B and D are Turing equivalent (written B ≡TD).

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A Method to Measure the Fuel Distribution and the Fuel Captured by V–Gutter Flameholder in High Speed Airstream

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/85-gt-42 ◽

1985 ◽

Author(s):

Gu Shan-Jian ◽

Yang Mao-Lin ◽

Li Xiang-Yi

Keyword(s):

Flow Rate ◽

Experimental Error ◽

High Speed ◽

Fuel Flow Rate ◽

Fuel Distribution ◽

Fuel Flow ◽

Sampling Condition ◽

Detailed Determination

A method to measure the fuel distribution and the percentage of fuel flow rate captured by a V-gutter flameholder in a high speed airstream has been developed. The effects of configuration and size of the probe and temprature of the sample mixture in the probe on measurement have been investigated. The detailed determination of isokinetic sampling condition is described. The effects of V-gutter geometry on flowfield have been considered. The total experimental error is of the order ±5%.

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