Nonlinear ion-mixing-mode particle transport in the dissipative trapped electron regime

Technical Report · Wed Sep 01 04:00:00 EDT 1993

DOI:https://doi.org/10.2172/10189767· OSTI ID:10189767

Ware, A S; Terry, P W ^[1]

---

1. Wisconsin Univ., Madison, WI (United States). Dept. of Physics

The nonlinear particle transport arising from the convection of nonadiabatic electron density by ion temperature gradient driven turbulence is examined for trapped electron collisionality regimes. The renormalized dissipative nonadiabatic trapped electron phase space density response is derived and used to calculate the nonlinear particle flux along with an ansatz for the turbulently broadened frequency spectrum. In the lower temperature end of this regime, trapped electrons are collisional and all components of the quasilinear particle flux are outward (i.e., in the direction of the gradients). Nonlinear effects can alter the phase between the nonadiabatic trapped electron phase space density and the electrostatic potential, producing inward components in the particle flux. Specifically, both turbulent shifting of the peak of the frequency spectrum and nonlinear source terms in the trapped electron response can give rise to inward components. However, in the dissipative regime these terms are small and the trapped electron response remains dominantly laminar. When the trapped electrons are collisionless, there is a temperature threshold above which the electron temperature gradient driven component of the quasilinear particle flux changes sign and becomes inward. For finite amplitude turbulence, however, turbulent broadening of both the electron collisional resonance and the frequency spectrum removes tills threshold., and the temperature gradient driven component remains outward.

• Research Organization: Wisconsin Univ., Madison, WI (United States). Center for Plasma Theory and Computation
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-86ER53218
• OSTI ID: 10189767
• Report Number(s): UW-CPTC--93-5; ON: DE94000989; BR: AT0500000/AT0520210
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700330
CHARGED-PARTICLE TRANSPORT
ELECTRON COLLISIONS
ELECTRON TEMPERATURE
ION TEMPERATURE
NONLINEAR PROBLEMS
PHASE SPACE
PLASMA KINETICS, TRANSPORT, AND IMPURITIES
TEMPERATURE GRADIENTS
TFTR TOKAMAK
TRAPPED ELECTRONS
TURBULENCE