Combined electron cyclotron ray tracing and transport code studies in the Compact Ignition Tokamak

Conference · Mon Jan 01 04:00:00 EST 1990

OSTI ID:6734179

Bonoli, P T; Englade, R C; Porkolab, M ^[1]; Kritz, A H ^[2]

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1. Massachusetts Inst. of Tech., Cambridge, MA (USA). Plasma Fusion Center
2. Hunter Coll., New York, NY (USA)

The Compact Ignition Tokamak (CIT) operating scenario is envisaged to consist of a start-up phase in which the toroidal magnetic field (B{sub T}), plasma current (I{sub P}) and central electron density (n{sub e}(0)) are simultaneously ramped, followed by a burn cycle and a ramp down cycle. Electron cyclotron radio-frequency (ECRF) power at fixed frequency is ideally suited to heating during the ramp up phase of CIT. The angle of injection of the incident microwave beam can be varied as the toroidal field is ramped, so as to maintain central rf-power deposition. Furthermore, since the EC wave is a propagating mode in vacuum, relatively high power densities can be easily coupled into a compact device. Finally, we note that recent advances in source technology makes ECR heating at (280--310) GHz a viable option. In order to realistically simulate this ramp up scenario, a combined code has been developed in which ECRF ray tracing and absorption, and MHD equilibrium calculation, and thermal and particle transport are treated self-consistently. Previous studies of electron cyclotron resonance heating in CIT were carried out using model profiles of rf absorption based on stand-alone ray tracing and absorption calculations. In addition, these studies held the plasma current, toroidal magnetic field, and density constant in time. In the present work, a time variation in these plasma quantities is imposed and ECRF power deposition is re-calculated during rf injection so as to more realistically and self-consistently simulate ECH-assisted start-up in CIT. The most recent CIT configuration calls for a toroidal field ramp to 11T. Thus, the present studies consider the use of an ECRF source frequency of 308 GHz, with EC waves launched in the ordinary mode of polarization.

• Research Organization: Hunter Coll., New York, NY (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: FG02-84ER53187
• OSTI ID: 6734179
• Report Number(s): CONF-900602-17; ON: DE90014097
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101* -- Fusion Energy-- Plasma Research-- Confinement
Heating
& Production
CHARGED-PARTICLE TRANSPORT
CLOSED PLASMA DEVICES
COMPACT IGNITION TOKAMAK
ECR HEATING
EQUILIBRIUM
HEATING
HIGH-FREQUENCY HEATING
MHD EQUILIBRIUM
PLASMA HEATING
RADIATION TRANSPORT
THERMONUCLEAR DEVICES
THERMONUCLEAR REACTORS
TOKAMAK DEVICES
TOKAMAK TYPE REACTORS
TRAJECTORIES