Anomalous transport: Difference between revisions

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There are several answers to this question. Since all equations describing the motion of charged particles in fields are known, including the effects of collisions, detailed numerical (gyrokinetic) simulations are possible.
There are several answers to this question. Since all equations describing the motion of charged particles in fields are known, including the effects of collisions, detailed numerical (gyrokinetic) simulations are possible.
<ref>[http://link.aps.org/doi/10.1103/PhysRevLett.77.71 A.M. Dinits et al, ''Scalings of Ion-Temperature-Gradient-Driven Anomalous Transport in Tokamaks'', Phys. Rev. Lett. '''77''' (1996) 71 - 74]</ref>
<ref>[http://link.aps.org/doi/10.1103/PhysRevLett.77.71 A.M. Dinits et al, ''Scalings of Ion-Temperature-Gradient-Driven Anomalous Transport in Tokamaks'', Phys. Rev. Lett. '''77''' (1996) 71 - 74]</ref>
However, due to the enormous disparity between the minimum and maximum scales involved (collision times vs. transport times, and the gyroradius vs. the machine size), this is a major challenge.  
However, due to the enormous disparity between the minimum and maximum scales involved (gyration times vs. transport times, and the gyroradius vs. the machine size), this is a major challenge.  


An alternative approach is to model the net effect of turbulence without simulating the fine detail.
An alternative approach is to model the net effect of turbulence without simulating the fine detail.