-
The beta-induced Alfvén eigenmodes (BAEs) with frequency chirping, observed in the HL-2A Tokamak, are analysed by a MHD-kinetic hybrid code MEGA. Realistic parameters are applied to the code, such as equilibrium, electron density and temperature, ion temperature, which is different from the kinetic Berk-Breizman theory. The BAEs are observed by Mirnov probes and soft X-ray arrays. Toroidal and porloidal mode number are confirmed to be n/m = 2/3 by using the phase shift method with toroidal filtered Mirnov signal arrays. And the soft X-ray arrays’ signal shows that BAEs are located at the core of the plasma and they have a relatively broad mode structure. The BAEs with up- and down-chirping are reproduced with MEGA code. The simulation results of mode structure accord well with experimental observations. Compared with up-chirping BAEs, the down-chirping BAEs are excited with higher plasma parameters and beta value, thus the energetic ion distribution in pitch angle has a broader width, and the beta value of energetic ions in the core of plasma and diffusion value are higher in the down-chirping simulation. The simulation results show that the phase space distribution of energetic ions affects the wave chirping direction. The energetic ions parallel to the magnetic field drive the up-chirping behavior. When the down-chirping behavior dominates, the density of energetic ions perpendicular to the magnetic field increases significantly. It shows that the down-chirping BAEs require higher beta and energetic ion density, which is consistent with the previous simulation result.
-
Keywords:
- MEGA code /
- beta-induced Alfvén eigenmodes /
- frequency chirping
[1] Chen L, Zonca F 2016 Rev. Mod. Phys. 88 015008Google Scholar
[2] Wong K L 1999 Plasma Phys. Control. Fusion 41 R1Google Scholar
[3] Heidbrink W W, Strait E J, Doyle E, et al. 1991 Nucl. Fusion 31 1635Google Scholar
[4] Podestà M, Bell R E, Crocker N A, et al. 2011 Nucl. Fusion 51 063035Google Scholar
[5] Wang X, Zonca F, Chen L 2010 Plasma Phys. Control. Fusion 52 115005Google Scholar
[6] Qi L Y, Dong J Q, Bierwage A, et al. 2013 Phys. Plasmas 20 032505Google Scholar
[7] Heidbrink W W, Strait E J, Chu M S, et al. 1993 Phys. Rev. Lett. 71 855Google Scholar
[8] Chen W, Ding X T, Yang Q W, et al. 2010 Phys. Rev. Lett. 105 185004Google Scholar
[9] Ding X T, Chen W 2018 Plasma Sci. Technol. 20 094008Google Scholar
[10] Yu L M, Chen W, Shi Z B, et al. 2021 Nucl. Fusion 61 026019Google Scholar
[11] Shi P W, Chen W, Shi Z B, et al. 2019 Nucl. Fusion 59 066015Google Scholar
[12] Xu M, Zhou T, Xu L Q, et al. 2018 Nucl. Fusion 58 124004Google Scholar
[13] Heidbrink W W 1995 Plasma Phys. Control. Fusion 37 937Google Scholar
[14] Shinohara K, Kusama Y, Takechi M, et al. 2001 Nucl. Fusion 41 603Google Scholar
[15] Pinches S D, Berk H L, Gryaznevich M P, et al. 2004 Plasma Phys. Control. Fusion 46 S47Google Scholar
[16] Fredrickson E D, Gorelenkov N N, Bell R E, et al. 2006 Nucl. Fusion 46 S926Google Scholar
[17] Classen I G J, Lauber Ph, Curran D, et al. 2011 Plasma Phys. Control. Fusion 53 124018Google Scholar
[18] Gryaznevich M P, Sharapov S E 2006 Nucl. Fusion 46 S942Google Scholar
[19] Chen W, Yu L M, Liu Y, et al. 2014 Nucl. Fusion 54 104002Google Scholar
[20] Berk H L, Breizman B N, Pekker M 1996 Phys. Rev. Lett. 76 1256Google Scholar
[21] Berk H L, Breizman B N, Petviashvili N V 1997 Phys. Lett. A 234 213Google Scholar
[22] Lilley M K, Breizman B N, Sharapov S E 2009 Phys. Rev. Lett. 102 195003Google Scholar
[23] Lesur M, Idomura Y, Shinohara K, et al. 2010 Phys. Plasmas 17 122311Google Scholar
[24] Zhang H S, Lin Z H, Holod I 2012 Phys. Rev. Lett. 109 025001Google Scholar
[25] Zhu J, Ma Z W, Fu G Y 2014 Nucl. Fusion 54 123020Google Scholar
[26] Wang X, Briguglio S, Chen L, et al. 2012 Phys. Rev. E 86 045401Google Scholar
[27] Todo Y 2006 Phys. Plasmas 13 082503Google Scholar
[28] Hou Y M, Chen W, Yu Y, et al. 2018 Nucl. Fusion 58 096028Google Scholar
[29] Hou Y M, Chen W, Yu L M, et al. 2021 Chin. Phys. Lett. 38 045202Google Scholar
[30] Wang X Q, Wang H, Todo Y, et al. 2021 Plasma Phys. Control. Fusion 63 015004Google Scholar
[31] Bierwage A, Shinohara K, Todo Y, et al. 2017 Nucl. Fusion 57 016036Google Scholar
[32] Shi Z B, Jiang M, Huang X L, et al. 2014 Rev. Sci. Instrum. 85 023510Google Scholar
[33] Liu C H, Wang Y Q, Feng Z, et al. 2015 JINST 10 C12026Google Scholar
[34] Li Y G, Zhou Y, Li Y, et al. 2017 Rev. Sci. Instrum. 88 083508Google Scholar
[35] Yang Z C, Jiang M, Shi Z B, et al. 2021 JINST 16 P05020Google Scholar
[36] Wei Y L, Yu D L, Liu L, et al. 2014 Rev. Sci. Instrum. 85 103503Google Scholar
[37] Chen W, Ding X T, Liu Y, et al. 2010 Nucl. Fusion 50 084008Google Scholar
[38] Yu L M, Chen W, Ji X Q, et al. 2021 Chin. Phy. Lett. 38 055202Google Scholar
[39] Shi P W, Chen W, Shi Z B, et al. 2017 Phys. Plasmas 24 042509Google Scholar
[40] Pei Y B, Xiang N, Hu Y J, et al. 2017 Phys. Plasmas 24 032507Google Scholar
[41] Hou Y M, Zhou H Y, Chen W, et al. 2023 Rev. Sci. Instrum. 94 033508Google Scholar
-
图 2 利用软X射线阵列信号得到的频谱图 (a) SX51, r = 2.5 cm,
$ \rho \sim 0.065$ ; (b) SX49, r=–7.3 cm,$ \rho \sim -0.1825$ ; (c) SX53, r = 12 cm,$ \rho\sim $ 0.3; (d) SX54, r = 16.3 cm,$ \rho\sim $ 0.4075Figure 2. Frequency spectrogram obtained with soft X-ray arrays’ signal: (a) SX51, r = 2.5 cm,
$ \rho\sim $ 0.065; (b) SX49, r=–7.3 cm,$ \rho\sim $ –0.1825; (c) SX53, r = 12 cm,$ \rho\sim $ 0.3; (d) SX54, r = 16.3 cm,$ \rho\sim $ 0.4075.图 4 (a) HL-2A装置第35491次放电实验, t = 908 ms对应的等离子体位形, 最外闭合磁面和q = 1.5面分别用红色、绿色线标注; (b) t = 908 ms与t = 920 ms时刻分别对应的总压强和q剖面分布
Figure 4. (a) Magnetic surface shape of HL-2A discharge
$ \# $ 35491 at 908 ms, the last-closed-flux-surface and q = 1.5 surface are indicated in red and green, respectively; (b) radial profiles of the total pressure and safety factor at t = 908 ms and t = 920 ms. -
[1] Chen L, Zonca F 2016 Rev. Mod. Phys. 88 015008Google Scholar
[2] Wong K L 1999 Plasma Phys. Control. Fusion 41 R1Google Scholar
[3] Heidbrink W W, Strait E J, Doyle E, et al. 1991 Nucl. Fusion 31 1635Google Scholar
[4] Podestà M, Bell R E, Crocker N A, et al. 2011 Nucl. Fusion 51 063035Google Scholar
[5] Wang X, Zonca F, Chen L 2010 Plasma Phys. Control. Fusion 52 115005Google Scholar
[6] Qi L Y, Dong J Q, Bierwage A, et al. 2013 Phys. Plasmas 20 032505Google Scholar
[7] Heidbrink W W, Strait E J, Chu M S, et al. 1993 Phys. Rev. Lett. 71 855Google Scholar
[8] Chen W, Ding X T, Yang Q W, et al. 2010 Phys. Rev. Lett. 105 185004Google Scholar
[9] Ding X T, Chen W 2018 Plasma Sci. Technol. 20 094008Google Scholar
[10] Yu L M, Chen W, Shi Z B, et al. 2021 Nucl. Fusion 61 026019Google Scholar
[11] Shi P W, Chen W, Shi Z B, et al. 2019 Nucl. Fusion 59 066015Google Scholar
[12] Xu M, Zhou T, Xu L Q, et al. 2018 Nucl. Fusion 58 124004Google Scholar
[13] Heidbrink W W 1995 Plasma Phys. Control. Fusion 37 937Google Scholar
[14] Shinohara K, Kusama Y, Takechi M, et al. 2001 Nucl. Fusion 41 603Google Scholar
[15] Pinches S D, Berk H L, Gryaznevich M P, et al. 2004 Plasma Phys. Control. Fusion 46 S47Google Scholar
[16] Fredrickson E D, Gorelenkov N N, Bell R E, et al. 2006 Nucl. Fusion 46 S926Google Scholar
[17] Classen I G J, Lauber Ph, Curran D, et al. 2011 Plasma Phys. Control. Fusion 53 124018Google Scholar
[18] Gryaznevich M P, Sharapov S E 2006 Nucl. Fusion 46 S942Google Scholar
[19] Chen W, Yu L M, Liu Y, et al. 2014 Nucl. Fusion 54 104002Google Scholar
[20] Berk H L, Breizman B N, Pekker M 1996 Phys. Rev. Lett. 76 1256Google Scholar
[21] Berk H L, Breizman B N, Petviashvili N V 1997 Phys. Lett. A 234 213Google Scholar
[22] Lilley M K, Breizman B N, Sharapov S E 2009 Phys. Rev. Lett. 102 195003Google Scholar
[23] Lesur M, Idomura Y, Shinohara K, et al. 2010 Phys. Plasmas 17 122311Google Scholar
[24] Zhang H S, Lin Z H, Holod I 2012 Phys. Rev. Lett. 109 025001Google Scholar
[25] Zhu J, Ma Z W, Fu G Y 2014 Nucl. Fusion 54 123020Google Scholar
[26] Wang X, Briguglio S, Chen L, et al. 2012 Phys. Rev. E 86 045401Google Scholar
[27] Todo Y 2006 Phys. Plasmas 13 082503Google Scholar
[28] Hou Y M, Chen W, Yu Y, et al. 2018 Nucl. Fusion 58 096028Google Scholar
[29] Hou Y M, Chen W, Yu L M, et al. 2021 Chin. Phys. Lett. 38 045202Google Scholar
[30] Wang X Q, Wang H, Todo Y, et al. 2021 Plasma Phys. Control. Fusion 63 015004Google Scholar
[31] Bierwage A, Shinohara K, Todo Y, et al. 2017 Nucl. Fusion 57 016036Google Scholar
[32] Shi Z B, Jiang M, Huang X L, et al. 2014 Rev. Sci. Instrum. 85 023510Google Scholar
[33] Liu C H, Wang Y Q, Feng Z, et al. 2015 JINST 10 C12026Google Scholar
[34] Li Y G, Zhou Y, Li Y, et al. 2017 Rev. Sci. Instrum. 88 083508Google Scholar
[35] Yang Z C, Jiang M, Shi Z B, et al. 2021 JINST 16 P05020Google Scholar
[36] Wei Y L, Yu D L, Liu L, et al. 2014 Rev. Sci. Instrum. 85 103503Google Scholar
[37] Chen W, Ding X T, Liu Y, et al. 2010 Nucl. Fusion 50 084008Google Scholar
[38] Yu L M, Chen W, Ji X Q, et al. 2021 Chin. Phy. Lett. 38 055202Google Scholar
[39] Shi P W, Chen W, Shi Z B, et al. 2017 Phys. Plasmas 24 042509Google Scholar
[40] Pei Y B, Xiang N, Hu Y J, et al. 2017 Phys. Plasmas 24 032507Google Scholar
[41] Hou Y M, Zhou H Y, Chen W, et al. 2023 Rev. Sci. Instrum. 94 033508Google Scholar
Catalog
Metrics
- Abstract views: 2119
- PDF Downloads: 48
- Cited By: 0