Effect of wall corrugations on lower-hybrid-wave launching and reflection
Abstract
The effect of wall corrugations on lower hybrid wave launching and reflection is considered and applied to the Alcator C 4.6-GHz RF experiment. A method of treating the effect of wall corrugations on wave launching is outlined. Using this formulism it is shown that placing four wall corrugations on each side of the Alcator C lower hybrid waveguide array increases its utility for current drive by better defining its low n/sub z/ power spectrum. a method of calculating the effect of bellows on the reflection of lower hybrid waves is also presented. This technique is applied to Alcator C to show that lower hybrid waves having k/sub ko/ 4 omega/c can have a significant fraction of their RF power shifted to k/ sub zo/ + or - 2 pi/d upon reflection, where d is the bellows spatial period. Furthermore, the shape of the incident RF power spectrum for k/sub zo/ 2 omega/c is distorted upon reflection. This effect can fundamentally modify wave trajectories that involve wall reflection.
- Publication:
-
Presented at the 5th Topical Conf. on Radio Freq. Plasma Heating
- Pub Date:
- February 1983
- Bibcode:
- 1983rfph.conf...22S
- Keywords:
-
- Corrugating;
- Plasma Focus;
- Plasmas (Physics);
- Radio Frequency Heating;
- Walls;
- Wave Reflection;
- Nuclear Fusion;
- Plasma Generators;
- Plasma Heating;
- Wave Propagation;
- Waveguides;
- Plasma Physics