A review of Alfven wave heating

Abstract

This paper r e v i w s the experimental status and recevt advances i n AlfvCn Wave Heating (AWH). We discuss the underlying physics of Alfven Wave Heating, as seen by the experiments. The use of AlfvCn Waves for plasna diagnosis is discussed. The results of plasna heating on TCA are s m a r i z e d . Apparent changes i n the current profile are inferred, caused by changes i n the evolving AlfvCn wave spectrun excited. The implications for AWH on larger devices are mentioned. KFrwoRDsAlfven Wave Heating; Tokamak; Kinetic Alfvgn Wave; Profile Cor?trol; Antema Systen; plasm Diagnostics; Tc9. IMTR3DilCTIONI n t h i s paper we shall review the recent experiwntal results obtained i n AlfvCn Wave Heating (AXH). The early experimental results have already been reviewed by Shohet (1978), and w shall not repeat that survey. An overview of the extensive theoretical mrk i n Lhis freqency range is beyond t h i s paper, and the current status has been very recently reviewed by Pppert and colleagues (1586). W e shall review the theoretical basis of .MX frm. the viewpint of the experimental observations made, and shall, i n f a c t , discover that mst of the imprtant concepts manifest themselves i n the results.

Alfvén wave dispersion behavior in single- and multicomponent plasmas

“…The resulting dispersion behavior is directly related to heat and energy transport in magnetized plasmas [3]. This is observed in laboratory [4][5][6][7] and fusion devices [8,9] as well as in space plasmas, e.g., the solar atmosphere [10] or during the interaction between the solar wind with the cusp regions of the terrestrial magnetoshere [11]. AWs are responsible for heating of the solar corona [12] and acceleration of the solar wind [13,14] by transferring energy from the sun's photosphere to the chromosphere in so-called flux tubes [15].…”

Dynamical plasma response to additional heating

“…The additional heating was provided by Alfven Waves launched by 8 phase-coherent antennae. The TCA Tokamak has been described in detail by CHEETHAM et al (1981) and the Alfven Wave excitation and heating experiments by COLLINS et al BESSON et al (1986). The r.f.…”

The Ion Cyclotron, Lower Hybrid and Alfven Wave Heating Methods

“…For the specific case of the ion-ion hybrid, and using Eq. (27) for simplicity, we shall also be able to show how to determine which sign to use in Eq. (43) of ref.…”

“…From the experimental point of view the most extensive experiments and analysis of Alfvén wave heating have been performed on the TCA tokamak 27 (R 0 =0.6m). Although antenna coupling and general wave behaviour appeared to be in agreement with the theory, generally speaking little plasma heating was observed while the main effect of the RF was a large density increase, sometimes interpreted as an increase in the particle confinement time.…”