Study on the Full Electromagnetic Model of Collective Thomson Scattering in Magnetic Confinement Fusion

doi:10.12096/j.2096-4528.pgt.24149

Abstract

Abstract:

Objectives Collective Thomson scattering (CTS) is one of the few fusion diagnostic technologies that can provide fast ion kinetic property measurement in the center of fusion devices. However, the physical models that CTS diagnosis relies on at home and abroad currently have problems such as lack of electromagnetic effects and inaccurate plasma dielectric properties, which hinders the development of CTS diagnostic theory. Therefore, it is urgent to develop a more comprehensive CTS physical model code to support the development of CTS diagnosis. Methods The establishment and derivation of the full electromagnetic model is introduced, and the similarities and differences between the full electromagnetic model and the electrostatic model are analysed. The spectrum characteristics of the full electromagnetic model CTS under different parameters are studied based on the HL-2A device. Results The full electromagnetic model is consistent with the electrostatic model results in conventional diagnosis. In addition, the full electromagnetic model has obvious advantages in diagnosing structures such as ion-Bernstein waves. The full electromagnetic model is used to optimize the system parameters for the CTS system of the HL-2A device. Conclusions In CTS spectrum research, the full electromagnetic model has more complete functions and huge potential, and can provide a powerful tool for CTS diagnosis of physical quantities such as ion ratios. In the future, based on more devices at home and abroad, the full electromagnetic model will have broader application prospects.

Key words: nuclear fusion, magnetic confinement fusion, fast ions, collective Thomson scattering, fully electromagnetic model, ion-Bernstein wave, ion ratio

CLC Number:

TK 01

Xinyu FANG, Donghui XIA, Mei HUANG, Feng ZHANG, Yonghua DING. Study on the Full Electromagnetic Model of Collective Thomson Scattering in Magnetic Confinement Fusion[J]. Power Generation Technology, 2025, 46(1): 200-208.

Figures/Tables 12

Fig. 1 CTS scattering geometric structure diagram

Tab. 1 Input parameters for the scattering function of the ITER Device

参数	数值
磁场强度B/T	5.6
入射波频率f_i/GHz	60
散射角 $θ$ /(°)	20
扰动波矢与磁场之间的夹角 $ϕ$ /(°)	10
电子密度n_e/ $m - 3$	$1020$
D离子密度n_D/ $m - 3$	$4.95 × 1019$
T离子密度n_T/ $m - 3$	$4.95 × 1019$
电子温度T_e/keV	25
D离子温度T_D/keV	25
T离子温度T_T/keV	25
快离子密度n_f/ $m - 3$	$0.05 × 1019$
快离子温度T_f/MeV	3.5
入射-散射模式	X-X

Tab. 1 Input parameters for the scattering function of the ITER Device

参数	数值
磁场强度B/T	5.6
入射波频率f_i/GHz	60
散射角 $θ$ /(°)	20
扰动波矢与磁场之间的夹角 $ϕ$ /(°)	10
电子密度n_e/ $m - 3$	$1020$
D离子密度n_D/ $m - 3$	$4.95 × 1019$
T离子密度n_T/ $m - 3$	$4.95 × 1019$
电子温度T_e/keV	25
D离子温度T_D/keV	25
T离子温度T_T/keV	25
快离子密度n_f/ $m - 3$	$0.05 × 1019$
快离子温度T_f/MeV	3.5
入射-散射模式	X-X

Fig. 2 Scattering function of the electrostatic model based on ITER device parameters

Fig. 3 Scattering function of the full electromagnetic model based on ITER device parameters

Fig. 4 scattering function of the full electromagnetic model and its scattering function components for different fluctuations

Fig. 5 CTS spectra power density with different H ion contents

Tab. 2 Input parameters for the CTS spectra power density with different H ion contents

参数	数值
磁场强度B/T	2.6
入射波频率f_i/GHz	110
入射波功率Pⁱ/kW	50
散射角 $θ$ /(°)	159
扰动波矢与磁场之间的夹角 $ϕ$ /(°)	93
电子密度n_e/ $m - 3$	$2 × 1019$
电子温度T_e/keV	1
离子温度T_i/keV	1
入射-散射模式	O-O
入射波束在测量处的半径wⁱ/mm	20
散射波束在测量处的半径w^s/mm	20

Tab. 2 Input parameters for the CTS spectra power density with different H ion contents

参数	数值
磁场强度B/T	2.6
入射波频率f_i/GHz	110
入射波功率Pⁱ/kW	50
散射角 $θ$ /(°)	159
扰动波矢与磁场之间的夹角 $ϕ$ /(°)	93
电子密度n_e/ $m - 3$	$2 × 1019$
电子温度T_e/keV	1
离子温度T_i/keV	1
入射-散射模式	O-O
入射波束在测量处的半径wⁱ/mm	20
散射波束在测量处的半径w^s/mm	20

Tab. 3 Input parameters for spectra power density of the HL-2A device

参数	数值
磁场强度B/T	2.0
入射波功率Pⁱ/kW	100
电子密度n_e/ $m - 3$	$2 × 1019$
电子温度T_e/keV	1.5
D离子密度n_D/ $m - 3$	$1.98 × 1019$
D离子温度T_D/keV	1.5
入射-散射模式/	O-O
快离子密度n_f/ $m - 3$	$0.02 × 1019$
快离子温度T_f/keV	45
入射波束在测量处的半径wⁱ/mm	20
散射波束在测量处的半径w^s/mm	20

Tab. 3 Input parameters for spectra power density of the HL-2A device

参数	数值
磁场强度B/T	2.0
入射波功率Pⁱ/kW	100
电子密度n_e/ $m - 3$	$2 × 1019$
电子温度T_e/keV	1.5
D离子密度n_D/ $m - 3$	$1.98 × 1019$
D离子温度T_D/keV	1.5
入射-散射模式/	O-O
快离子密度n_f/ $m - 3$	$0.02 × 1019$
快离子温度T_f/keV	45
入射波束在测量处的半径wⁱ/mm	20
散射波束在测量处的半径w^s/mm	20

Fig. 6 105 GHz CTS diagnostics spectra power density under scattering geometries

Fig. 7 140 GHz CTS diagnostics spectra power density under scattering geometries

Fig. 8 Ion-Bernstein wave structure in the CTS spectra power density of the HL-2A device

Fig. 9 Spectra power density of 105 GHz CTS diagnostic at two electron temperatures

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