Author: Miklos Porkolab
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
RF Heating and Current Drive Experiments on the Alcator C and Versator II Tokamaks
Lower Hybrid Heating & Current Drive Experiments on the Alcator C and Versator II Tokamaks
Lower Hybrid Rf Heating Experiments in the MIT Alcator A, C and Versator II Tokamaks
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Experimental results on lower hybrid heating in the Alcator A and the Versator II tokamaks with power levels up to 90 kW are presented. In Alcator A a double waveguide grill, and in Versator II a 4 waveguide grill with arbitrary phasing are used. Also, a 6 waveguide grill experiment in Versator II is described which launches a travelling wave aimed at driving toroidal currents. The forthcoming lower hybrid heating experiment in Alcator C, utilizing four 4 x 4 waveguide arrays with power levels up to 4 MW, is also described.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Experimental results on lower hybrid heating in the Alcator A and the Versator II tokamaks with power levels up to 90 kW are presented. In Alcator A a double waveguide grill, and in Versator II a 4 waveguide grill with arbitrary phasing are used. Also, a 6 waveguide grill experiment in Versator II is described which launches a travelling wave aimed at driving toroidal currents. The forthcoming lower hybrid heating experiment in Alcator C, utilizing four 4 x 4 waveguide arrays with power levels up to 4 MW, is also described.
Lower Hybrid Heating and Current Drive, and Ion Cyclotron Heating Experiments on the Alcator C and the Versator II Tokamaks
Lower Hybrid Current Drive Experiments on the Alcator C and the Versator II Tokamaks
Lower Hybrid Current Drive Experiments on the MIT Alcator C and Versator II Tokamaks
Lower-hybrid-heating Experiments on the Alcator C and the Versator II Tokamaks
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Initial results are reported from lower hybrid wave heating experiments carried out on the MIT Alcator C and Versator II tokamaks. In the Alcator C experiments a 4 waveguide array, with internally brazed ceramic windows has been used to inject 160 kW of microwave power at 4.6 GHz into the plasma with n0 less than or equal to 1 x 1015 cm−3, and B0 less than or equal to 12 T. An RF power density of 8 kW/cm2 has been transmitted into the plasma without RF breakdown. RF coupling studies show optimal coupling (R less than or equal to 10%) when the local density at the waveguide mouth is 25 to 50 times overdense. Initial heating experiments show an ion tail formation in hydrogen discharge peaking at a density of anti n approx. = 2.7 x 1014 cm−3 at B = 8.9 T, and bulk ion heating at a density of anti n approx. = 1.5 x 1014 c−3 at B approx. = 11 T. Evidence of RF current enhancement has been observed at a density of n approx. = 3 x 1013 cm−3. In the Versator II tokamak initial ion heating studies have been carried out using an 800 MHz, 140 kW klystron. With 50 kW of net RF power injected through a 4 waveguide grill at B = 1.3 T and anti n = 2.5 x 1013 cm−3, Doppler broadening of the OVII and NVI lines shows a .delta.T/sub i/ = 50 eV rise in the bulk ion temperature. A significant RF produced ion tail is also observed by charge exchange analysis. We have succeeded in combining a toroidal ray-tracing code and a 1-D transport code to study the heating density bands and heating efficiencies.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Initial results are reported from lower hybrid wave heating experiments carried out on the MIT Alcator C and Versator II tokamaks. In the Alcator C experiments a 4 waveguide array, with internally brazed ceramic windows has been used to inject 160 kW of microwave power at 4.6 GHz into the plasma with n0 less than or equal to 1 x 1015 cm−3, and B0 less than or equal to 12 T. An RF power density of 8 kW/cm2 has been transmitted into the plasma without RF breakdown. RF coupling studies show optimal coupling (R less than or equal to 10%) when the local density at the waveguide mouth is 25 to 50 times overdense. Initial heating experiments show an ion tail formation in hydrogen discharge peaking at a density of anti n approx. = 2.7 x 1014 cm−3 at B = 8.9 T, and bulk ion heating at a density of anti n approx. = 1.5 x 1014 c−3 at B approx. = 11 T. Evidence of RF current enhancement has been observed at a density of n approx. = 3 x 1013 cm−3. In the Versator II tokamak initial ion heating studies have been carried out using an 800 MHz, 140 kW klystron. With 50 kW of net RF power injected through a 4 waveguide grill at B = 1.3 T and anti n = 2.5 x 1013 cm−3, Doppler broadening of the OVII and NVI lines shows a .delta.T/sub i/ = 50 eV rise in the bulk ion temperature. A significant RF produced ion tail is also observed by charge exchange analysis. We have succeeded in combining a toroidal ray-tracing code and a 1-D transport code to study the heating density bands and heating efficiencies.