Sensitivity of global energy confinement to the boundary condition due to coupling of MHD and transport processes

MHD instabilities are governed by the transport-determined plasma profiles, and the transport process is affected in turn by the instabilities. Using a one-dimensional code, we have investigated the inter-relationship between instabilities, transport and plasma profile in a tokamak discharge. The results show that the global energy confinement becomes strongly dependent on the boundary transport condition owing to strong coupling between them, and a higher edge temperature would ensure a higher core temperature and hence greater global energy confinement.

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Ein einfaches statistisches Modell für Transportvorgänge mit beschränkter Ausbreitungsgeschwindigkeit. II

Zeitschrift für Naturforschung A ◽

10.1515/zna-1970-8-906 ◽

1970 ◽

Vol 25 (8-9) ◽

pp. 1207-1212

Author(s):

J.U. Keller

Keyword(s):

Brownian Motion ◽

Random Walk ◽

Transport Process ◽

Transport Processes ◽

Random Walk Process ◽

One Dimensional ◽

Cubic Lattice ◽

History Of ◽

Velocity Of Propagation ◽

External Forces

Abstract In a paper 1 published recently a one-dimensional random walk-model for transport-processes with bounded velocity of propagation like heat conduction, diffusion and Brownian-motion has been given. Now this model is generalized to processes in 3 dimensions. We consider the transport process as a random-walk process in a primitive cubic lattice without boundaries and without external forces. The jump-probabilities of the random-walk-particle generally depend on the history of the particle. The resulting transport-equation contains terms which are due to the structure of the lattice not invariant under rotation. Further on this equation always describes transport-processes with bounded velocity of propagation.

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Global energy confinement under coupling of the transport process with magnetohydrodynamic modes

Physics of Plasmas ◽

10.1063/1.871240 ◽

1995 ◽

Vol 2 (7) ◽

pp. 2753-2759

Author(s):

X. H. Deng ◽

Y. P. Huo ◽

C. Zhang ◽

J. F. Wang ◽

S. Wang

Keyword(s):

Transport Process ◽

Global Energy ◽

Energy Confinement

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One-Dimensional Fin-Tip Boundary Condition Correction II

Heat Transfer Engineering ◽

10.1080/01457630152496304 ◽

2001 ◽

Vol 22 (5) ◽

pp. 35-40 ◽

Cited By ~ 1

Author(s):

D. C. Look Jr ◽

Arvind Krishnan

Keyword(s):

Boundary Condition ◽

One Dimensional

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Using constant base current as a boundary condition for one-dimensional AlGaAs/GaAs heterojunction bipolar transistor simulation

Electronics Letters ◽

10.1049/el:19900964 ◽

1990 ◽

Vol 26 (18) ◽

pp. 1501 ◽

Cited By ~ 8

Author(s):

L.L. Liou ◽

C.I. Huang

Keyword(s):

Boundary Condition ◽

Bipolar Transistor ◽

Heterojunction Bipolar Transistor ◽

One Dimensional ◽

Base Current

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AN ANALYTIC SOLUTION FOR ONE-DIMENSIONAL DISSIPATIONAL STRAIN-GRADIENT PLASTICITY

The ANZIAM Journal ◽

10.1017/s1446181109000066 ◽

2009 ◽

Vol 50 (3) ◽

pp. 407-420

Author(s):

ROGER YOUNG

Keyword(s):

Boundary Condition ◽

Strain Gradient ◽

Analytic Solution ◽

Strain Gradient Plasticity ◽

Numerical Results ◽

Gradient Plasticity ◽

One Dimensional ◽

Numerical Result ◽

Formulation Analysis ◽

The One

AbstractAn analytic solution is developed for the one-dimensional dissipational slip gradient equation first described by Gurtin [“On the plasticity of single crystals: free energy, microforces, plastic strain-gradients”, J. Mech. Phys. Solids48 (2000) 989–1036] and then investigated numerically by Anand et al. [“A one-dimensional theory of strain-gradient plasticity: formulation, analysis, numerical results”, J. Mech. Phys. Solids53 (2005) 1798–1826]. However we find that the analytic solution is incompatible with the zero-sliprate boundary condition (“clamped boundary condition”) postulated by these authors, and is in fact excluded by the theory. As a consequence the analytic solution agrees with the numerical results except near the boundary. The equation also admits a series of higher mode solutions where the numerical result corresponds to (a particular case of) the fundamental mode. Anand et al. also established that the one-dimensional dissipational gradients strengthen the material, but this proposition only holds if zero-sliprate boundary conditions can be imposed, which we have shown cannot be done. Hence the possibility remains open that dissipational gradient weakening may also occur.

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