FRC translation dynamics and plasma confinement properties in FRX-C/T

Rej, D J; Tuszewski, M; Armstrong, W T; Chrien, R E; Klinger, P L; McKenna, K F; Siemon, R E; Sherwood, E G; Milroy, R D

Title: FRC translation dynamics and plasma confinement properties in FRX-C/T

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Abstract

In the FRX-C/T experiment field-reversed configuration plasmas are translated over 16 meters without inducing instabilities or enhanced transport. The plasmas are formed in either a puff or static D/sub 2/ fill and they are accelerated to axial speeds of up to the ion thermal velocity. The observed acceleration dynamics agree with 2-D MHD simulations. When translated into reduced external magnetic fields, FRCs are observed to accelerate, expand, and cool in approximate agreement with adiabatic theory. The plasmas reflect from an external mirror with negligible loss in thermal energy, particle inventory, and poloidal magnetic flux. After each reflection the axial kinetic energy is reduced by approximately 50%. Because of this reduction, FRCs are readily trapped without the need of pulsed gate magnet coils. Translation has also allowed the scaling of FRC confinement over an extended parameter space with plasma dimensions, temperatures, and densities varying by factors of 2 to 4. An empirical scaling law of the observed nonclassical particle confinement shows departures from the lower-hybrid-drift scaling. Particle transport accounts for approximately one-half of the total energy loss. The confinement parameter, n tau/sub E/ approx. = 10/sup 11/ s/cm/sup 3/, is observed with n approx. = 10/sup 15/ cm/sup -3/ and T/submore » i/ approx. = 0.6 keV.« less

Authors:: Rej, D J; Tuszewski, M; Armstrong, W T; Chrien, R E; Klinger, P L; McKenna, K F; Siemon, R E; Sherwood, E G; Milroy, R D

Publication Date:: Sun Jan 01 00:00:00 EST 1984

Research Org.:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Mathematical Sciences Northwest, Inc., Bellevue, WA (USA)

OSTI Identifier:: 6381680

Report Number(s):: LA-UR-84-3289; CONF-8411111-2
ON: DE85002386

DOE Contract Number:: W-7405-ENG-36

Resource Type:: Conference

Resource Relation:: Conference: Japan/US joint symposium on compact toroid research, Hiroshima, Japan, 13 Nov 1984

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; REVERSE-FIELD PINCH; PLASMA CONFINEMENT; ACCELERATION; COMPACT TORUS; ENERGY LOSSES; SCALING LAWS; CLOSED PLASMA DEVICES; CONFINEMENT; LOSSES; PINCH EFFECT; THERMONUCLEAR DEVICES; TORI; 700101* - Fusion Energy- Plasma Research- Confinement, Heating, & Production

Citation Formats


                    Rej, D J, Tuszewski, M, Armstrong, W T, Chrien, R E, Klinger, P L, McKenna, K F, Siemon, R E, Sherwood, E G, and Milroy, R D. FRC translation dynamics and plasma confinement properties in FRX-C/T.  United States: N. p., 1984. 
        Web.

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                    Rej, D J, Tuszewski, M, Armstrong, W T, Chrien, R E, Klinger, P L, McKenna, K F, Siemon, R E, Sherwood, E G, & Milroy, R D. FRC translation dynamics and plasma confinement properties in FRX-C/T.  United States.

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                    Rej, D J, Tuszewski, M, Armstrong, W T, Chrien, R E, Klinger, P L, McKenna, K F, Siemon, R E, Sherwood, E G, and Milroy, R D. 1984.  
        "FRC translation dynamics and plasma confinement properties in FRX-C/T".  United States.  https://www.osti.gov/servlets/purl/6381680.

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@article{osti_6381680,

  title        = {FRC translation dynamics and plasma confinement properties in FRX-C/T},

  author       = {Rej, D J and Tuszewski, M and Armstrong, W T and Chrien, R E and Klinger, P L and McKenna, K F and Siemon, R E and Sherwood, E G and Milroy, R D},

  abstractNote = {In the FRX-C/T experiment field-reversed configuration plasmas are translated over 16 meters without inducing instabilities or enhanced transport. The plasmas are formed in either a puff or static D/sub 2/ fill and they are accelerated to axial speeds of up to the ion thermal velocity. The observed acceleration dynamics agree with 2-D MHD simulations. When translated into reduced external magnetic fields, FRCs are observed to accelerate, expand, and cool in approximate agreement with adiabatic theory. The plasmas reflect from an external mirror with negligible loss in thermal energy, particle inventory, and poloidal magnetic flux. After each reflection the axial kinetic energy is reduced by approximately 50%. Because of this reduction, FRCs are readily trapped without the need of pulsed gate magnet coils. Translation has also allowed the scaling of FRC confinement over an extended parameter space with plasma dimensions, temperatures, and densities varying by factors of 2 to 4. An empirical scaling law of the observed nonclassical particle confinement shows departures from the lower-hybrid-drift scaling. Particle transport accounts for approximately one-half of the total energy loss. The confinement parameter, n tau/sub E/ approx. = 10/sup 11/ s/cm/sup 3/, is observed with n approx. = 10/sup 15/ cm/sup -3/ and T/sub i/ approx. = 0.6 keV.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/6381680},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sun Jan 01 00:00:00 EST 1984},

  month        = {Sun Jan 01 00:00:00 EST 1984}

}

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