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HL-2M托卡马克装置中螺旋波与低杂波的协同电流驱动

刘冠男 李新霞 刘洪波 孙爱萍

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HL-2M托卡马克装置中螺旋波与低杂波的协同电流驱动

刘冠男, 李新霞, 刘洪波, 孙爱萍

Synergistic current drive of helicon wave and lower hybrid wave in HL-2M

Liu Guan-Nan, LI Xin-Xia, Liu Hong-Bo, Sun Ai-Ping
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  • 螺旋波是一种快磁声波, 在托卡马克等离子体中通过电子朗道阻尼和渡越期磁泵效应能够高效地离轴驱动等离子体电流. 依托HL-2M装置, 根据快波等离子体色散关系, 分析获得了螺旋波强阻尼条件下对应的波参数范围; 然后, 通过联合GENRAY/CQL3D计算程序, 针对HL-2M装置稳态运行模式下的螺旋波和低杂波协同电流驱动开展了模拟研究. 研究结果表明: 高比压等离子体参数下的螺旋波和低杂波都可呈现波射线能量强吸收的现象; 双波协同使得波驱动的等离子体电流分布在较大的径向位置范围($\rho = $0.2—0.9)内; 同时, 螺旋波在平行磁场方向加速电子, 导致了更多的电子进入低杂波共振区, 从而有效地增大了两支波的总驱动电流. 此外, 在强阻尼条件下, 系统地研究了螺旋波平行折射率对双波协同电流驱动的影响, 结果表明双波总是呈现正协同效应, 协同因子高达1.18.
    Non-inductive current drive plays a crucial role in tokamak, especially for its steady state operations. Recently, the helicon wave (HW) has been regarded as a promising tool for driving off-axis plasma current in reactor-grade machine. The lower-hybrid wave (LHW) is the most effective radio-frequency current drive method, however, it has the drawback, which is limited by the conditions of wave accessibility in the high parameter tokamak, making the wave power usually damped at the plasma edge. HW can spiral towards the plasma centre directly under a high electron density. To obtain a long pulse steady state operation of reactor tokamak, the complementarity of HW and LHW in the aspect of driven current distribution in the high parameter tokamak is considered. The synergy current drive of the HW and the LHW is studied numerically in the steady-state scenario of HL-2M. According to the fast wave dispersion relation of plasma, the HW parameters, including its wave frequency and launched parallel refractive index, are obtained firstly. Results of GENRAY code simulation show that a single pass wave power absorption of the HW can be obtained generally through the electron Landau damping and transit time magnetic pumping effects. On the other hand, the LHW parameters are adopted from the equipped system on the machine. Results of single pass wave absorption are also obtained in the case of LHW. And then, the synergy effects of HW and LHW are studied numerically based on the GENRAY/CQL3D models. The cooperation of these two waves results in a broad plasma current distribution along the radial direction ($\rho = $0.2-0.9) in the machine. Taking the electron distribution functions of these waves into account, it is clear that the electrons are accelerated by the HW in the parallel magnetic field direction, resulting in more electrons entering the region of LHW resonance area. As the consequence, a net plasma current appears. Furthermore, a fine-grained parametric scan is performed by changing the launched parallel refractive index of HW, and the results indicate that positive synergy effects can be generally observed once the related wave current drive profiles are overlapped. Finally, the synergy factor is shown to be proportional to this overlap and reaches its maximum value of 1.18 in HL-2M.
      通信作者: 李新霞, li_xx@usc.edu.cn ; 孙爱萍, apsun@swip.ac.cn
    • 基金项目: 国家磁约束核聚变能发展研究专项(批准号: 2019YFE03040004)和国家自然科学基金(批准号: 11775108)资助的课题.
      Corresponding author: LI Xin-Xia, li_xx@usc.edu.cn ; Sun Ai-Ping, apsun@swip.ac.cn
    • Funds: Project supported by the National Magnetic Confinement Nuclear Fusion Energy Development Research of China (Grant No. 2019YFE03040004) and the National Natural Science Foundation of China (Grant No. 11775108).
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    Chiu S C, Chan V S, Harvey R W, Porkolab M 1989 Nucl. Fusion 29 2175Google Scholar

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    Peysson Y, Decker J, Nilsson E, Artaud J F, Ekedahl A, Goniche M, Hillairet J, Ding B, Li M, Bonoli P T, Shiraiwa S, Madi M 2016 Plasma Phys. Controlled Fusion 58 044008Google Scholar

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    Wang Z T, Long Y X, Dong J Q, He Z X 2013 Chin. Phys. B 22 095201Google Scholar

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    Phillips C K, Bell R E, Berry L A, Bonoli P T, Harvey R W, Hosea J C, Jaeger E F, LeBlanc B P, Ryan P M, Taylor G, Valeo E J, Wilgen J B, Wilson J R, Wright J C, Yuh H, NSTX Team 2009 Nucl. Fusion 49 075015Google Scholar

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    Huang C B, Gao X, Liu Z X, Han X, Zhang T, Wang Y M, Zang S B, Kong D F, EAST Team 2016 Plasma Phys. Controlled Fusion 58 075005Google Scholar

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    Duan X R, Ding X T, Dong J Q, Yan L W, Liu Y, Huang Y, Song X M, Zou X L, Xu M, Yang Q W, Liu D Q, Rao J, Xuan W M, Chen L Y, Mao W C, Wang Q M, Cao J Y, Lei G J, Zhang J H, Li X D, Chen W, Zhao K J, Xiao W W 2013 Nucl. Fusion 53 104009Google Scholar

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    Li X X, Xiang N, Gan C Y 2015 Chin. Phys. Lett. 32 035202Google Scholar

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    Prater R, Moeller C P, Pinsker R I, Porkolab M, Meneghini O, Vdovin V L 2014 Nucl. Fusion 54 083024Google Scholar

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    Vdovin V L 2013 Plasma Phys. Rep. 39 95Google Scholar

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    Van Compernolle B, Brookman M, Pinsker R, Moeller C, Squire J, Garofalo A M, Nagy A, Torrezan A, Ponce D, Pawley C, Chowdury S, Crocker N, Degrandchamp G, Hinson E, Lohr J, Marinoni A, Martin E, Petty C, Porkolab M, Rost C, Schmitz O, Thome K, Wang Q H, Watkins J, Zeller K 2021 63rd Annual Meeting of the APS Division of Plasma Physics Pittsburgh, November 8–12, 2021 UO07

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    Liu H B, Liu G N, Sun A P, Xiao Z Y, Li X X 2022 J. Korean Phys. Soc. 81 397Google Scholar

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    Fidone I, Giruzzi G, Granata G, Meyer R L 1984 Phys. Fluids. 27 2468Google Scholar

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    Kawashima H, Yamamoto T, Hoshino K, Uesugi Y, Mori M, Suzuki N 1991 Nucl. Fusion 31 495Google Scholar

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    Maekawa T, Maehara T, Minami T, Kishigami Y, Kishino T, Makino K, Hanada K, Nakamura M, Terumichi Y, Tanaka S 1993 Phys. Rev. Lett. 70 2561Google Scholar

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    Maehara T, Yoshimura S, Minami T, Hanada K, Nakamura M, Maekawa T, Terumichi Y 1998 Nucl. Fusion 38 39Google Scholar

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    Harvey R W, Chiu S C, McCoy M G, Kerbel G D, Smith G R, Mau T K 1991 Proc. of IAEA TCM on Fast Wave Current Drive in Reactor Scale Tokamaks Arles, France, September 23–25, 1991 p135

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    Yang Y L, Xiang N, Hu Y M 2017 Phys. Plasmas 24 032502Google Scholar

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    Yang Y L, Xiang N, Hu Y M 2017 Phys. Plasmas 24 082503Google Scholar

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    Yin L, Zheng P W, Gong X Y, Yang C, Yin X H, Song C Y, Huang Q H, Chen Y, Zhong Y J 2022 Nucl. Fusion 62 066023Google Scholar

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    Pinsker R I, Porkolab M, Petty C C, Prater R, Moeller C P 2015 AIP Conference Proceedings 1689 080012Google Scholar

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    Kennel C F, Engelmann F 1966 Phys. Fluids 9 2377Google Scholar

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    刘祖光 2020 硕士学位论文 (衡阳: 南华大学)

    Liu Z G 2020 M. S. Thesis (Hengyang: University of South China

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    The GENRAY Ray Tracing Code, Smirnov A P, Harvey R W https://compxco.com/Genray_manual.pdf [2003-03-17

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    Artaud J F, Imbeaux F, Garcia J, Giruzzi G, Aniel T, Basiuk V, Bécoulet A, Bourdelle C, Buravand Y, Decker J, Dumont R, Eriksson L G, Garbet X, Guirlet R, Hoang G T, Huynh P, Joffrin E, Litaudon X, Maget P, Moreau D, Nouailletas R, Pégourié B, Peysson Y, Schneider M, Urban J 2018 Nucl. Fusion 58 105001Google Scholar

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    李新霞, 李国壮, 刘洪波 2020 物理学报 69 145201Google Scholar

    Li X X, Li G Z, Liu H B 2020 Acta Phys. Sin. 69 145201Google Scholar

    [26]

    杨友磊, 胡业民, 项农 2017 物理学报 66 245202Google Scholar

    Yang Y L, Hu Y M, Xiang N 2017 Acta Phys. Sin. 66 245202Google Scholar

  • 图 1  HL-2M装置稳态运行模式下的等离子体平衡参数 (a)电子温度和密度分布; (b)有效电荷和安全因子分布

    Fig. 1.  Radial profiles of (a) electron temperature and density for the HL-2M steady-state scenario; radial profiles of (b) effective charge and safety factor for the HL-2M steady-state scenario.

    图 2  在HL-2M装置放电条件下通过HW强阻尼条件求得的$ 2\overline {k_{ \bot {\text{I}}}^{(\rm e)}} a $值的等高线图 (a) ${\beta _{\text{e}}}\sim$2.0%时, $ 2\overline {k_{ \bot {\text{I}}}^{(\rm e)}} a $关于${\xi _{\text{e}}}$和$f$的等高线图; (b) $ {f_{{\text{HW}}}} = $0.6 GHz时, $ 2\overline {k_{ \bot {\text{I}}}^{(\rm e)}} a $关于${\xi _{\text{e}}}$和${\beta _{\text{e}}}$的等高线图

    Fig. 2.  Contours of $ 2\overline {k_{ \bot {\text{I}}}^{(\rm e)}} a $ as a function of (a) ${\xi _{\text{e}}}$ and $f$ with ${\beta _{\text{e}}}\sim$2.0% for the strong damping condition of the HW of HL-2M; contours of $ 2\overline {k_{ \bot {\text{I}}}^{(\rm e)}} a $ as a function of (b) ${\xi _{\text{e}}}$ and ${\beta _{\text{e}}}$ with ${f_{{\text{HW}}}} = $0.6 GHz for the strong damping condition of the HW of HL-2M.

    图 3  HL-2M装置LHW/HW波射线传播轨迹, 其中, ${f_{{\text{LH}}}} = $3.7 GHz, ${n_{{{/ /\rm LH}}}}$分别取2.2和2.6; ${f_{{\text{HW}}}} = $0.6 GHz, ${n_{{{/ / \rm HW}}}} = $3.7

    Fig. 3.  Ray trajectories of the HW with ${f_{{\text{HW}}}} = $0.6 GHz and ${n_{{{/ / \rm HW}}}} = $3.7 in HL-2M, as well as the LHW with ${f_{{\text{LH}}}} = $3.7 GHz and ${n_{{{/ /\rm LH}}}}$ of 2.2 and 2.6 respectively.

    图 4  HW, LHW和双波协同(HW+LH)驱动下的电流密度剖面

    Fig. 4.  Driven current density profiles for the HW, the LHW, and the HW+ LHW.

    图 5  (a)麦克斯韦(${D_{{\text{Maxwell}}}}$), HW(${D_{{\text{HW}}}}$), LHW(${D_{{\text{LH}}}}$)单独作用下和双波协同作用(${D_{{\text{HW}} + {\text{LH}}}}$)下的电子平行分布; (b) 图5(a)中黑色矩形框的放大区域

    Fig. 5.  (a) Parallel electron distributions of the Maxwell, the HW, the LHW, and HW+LHW; (b) the enlarged area of the black rectangular box in Fig. 5(a).

    图 6  波电场加速下的电子通量、波电场及碰撞作用下电子总通量的对数及射频波准线性扩散和碰撞作用下的电子分布 (a)—(c)分别为HW, LHW以及双波协同下的电子通量; (d)—(f) 分别为HW, LHW以及双波协同下的电子总通量的对数; (g)—(i)分别为HW, LHW以及双波协同下的电子分布

    Fig. 6.  (a)–(c) Electron flux of the HW, the LHW, and the HW+LHW respectively; (d)–(f) the logarithms of the total electron fluxes for the case of Fig. 6(a)-(c); (g)–(i) contours of the electron distribution function for the case of Fig. 6(a)-(c).

    表 1  不同HW平行折射率下的协同效果

    Table 1.  Synergistic effect in different HW parallel refractive indexes.

    ${n_{{{/ / \rm HW}}}}$${I_{{\text{HW}} + {\text{LH}}}}/{\text{kA}}$${I_{{\text{HW}}}}/{\text{kA}}$${I_{{\text{LH}}}}/{\text{kA}}$${F_{{\text{syn}}}}$
    3.31228.0440.6669.01.18
    3.51211.1433.3669.01.16
    3.71180.6416.0669.01.14
    3.91151.6396.5669.01.13
    4.11120.5377.0669.01.11
    下载: 导出CSV
  • [1]

    Chiu S C, Chan V S, Harvey R W, Porkolab M 1989 Nucl. Fusion 29 2175Google Scholar

    [2]

    Peysson Y, Decker J, Nilsson E, Artaud J F, Ekedahl A, Goniche M, Hillairet J, Ding B, Li M, Bonoli P T, Shiraiwa S, Madi M 2016 Plasma Phys. Controlled Fusion 58 044008Google Scholar

    [3]

    Wang Z T, Long Y X, Dong J Q, He Z X 2013 Chin. Phys. B 22 095201Google Scholar

    [4]

    Phillips C K, Bell R E, Berry L A, Bonoli P T, Harvey R W, Hosea J C, Jaeger E F, LeBlanc B P, Ryan P M, Taylor G, Valeo E J, Wilgen J B, Wilson J R, Wright J C, Yuh H, NSTX Team 2009 Nucl. Fusion 49 075015Google Scholar

    [5]

    Huang C B, Gao X, Liu Z X, Han X, Zhang T, Wang Y M, Zang S B, Kong D F, EAST Team 2016 Plasma Phys. Controlled Fusion 58 075005Google Scholar

    [6]

    Duan X R, Ding X T, Dong J Q, Yan L W, Liu Y, Huang Y, Song X M, Zou X L, Xu M, Yang Q W, Liu D Q, Rao J, Xuan W M, Chen L Y, Mao W C, Wang Q M, Cao J Y, Lei G J, Zhang J H, Li X D, Chen W, Zhao K J, Xiao W W 2013 Nucl. Fusion 53 104009Google Scholar

    [7]

    Li X X, Xiang N, Gan C Y 2015 Chin. Phys. Lett. 32 035202Google Scholar

    [8]

    Prater R, Moeller C P, Pinsker R I, Porkolab M, Meneghini O, Vdovin V L 2014 Nucl. Fusion 54 083024Google Scholar

    [9]

    Vdovin V L 2013 Plasma Phys. Rep. 39 95Google Scholar

    [10]

    Van Compernolle B, Brookman M, Pinsker R, Moeller C, Squire J, Garofalo A M, Nagy A, Torrezan A, Ponce D, Pawley C, Chowdury S, Crocker N, Degrandchamp G, Hinson E, Lohr J, Marinoni A, Martin E, Petty C, Porkolab M, Rost C, Schmitz O, Thome K, Wang Q H, Watkins J, Zeller K 2021 63rd Annual Meeting of the APS Division of Plasma Physics Pittsburgh, November 8–12, 2021 UO07

    [11]

    Liu H B, Liu G N, Sun A P, Xiao Z Y, Li X X 2022 J. Korean Phys. Soc. 81 397Google Scholar

    [12]

    Fidone I, Giruzzi G, Granata G, Meyer R L 1984 Phys. Fluids. 27 2468Google Scholar

    [13]

    Kawashima H, Yamamoto T, Hoshino K, Uesugi Y, Mori M, Suzuki N 1991 Nucl. Fusion 31 495Google Scholar

    [14]

    Maekawa T, Maehara T, Minami T, Kishigami Y, Kishino T, Makino K, Hanada K, Nakamura M, Terumichi Y, Tanaka S 1993 Phys. Rev. Lett. 70 2561Google Scholar

    [15]

    Maehara T, Yoshimura S, Minami T, Hanada K, Nakamura M, Maekawa T, Terumichi Y 1998 Nucl. Fusion 38 39Google Scholar

    [16]

    Harvey R W, Chiu S C, McCoy M G, Kerbel G D, Smith G R, Mau T K 1991 Proc. of IAEA TCM on Fast Wave Current Drive in Reactor Scale Tokamaks Arles, France, September 23–25, 1991 p135

    [17]

    Yang Y L, Xiang N, Hu Y M 2017 Phys. Plasmas 24 032502Google Scholar

    [18]

    Yang Y L, Xiang N, Hu Y M 2017 Phys. Plasmas 24 082503Google Scholar

    [19]

    Yin L, Zheng P W, Gong X Y, Yang C, Yin X H, Song C Y, Huang Q H, Chen Y, Zhong Y J 2022 Nucl. Fusion 62 066023Google Scholar

    [20]

    Pinsker R I, Porkolab M, Petty C C, Prater R, Moeller C P 2015 AIP Conference Proceedings 1689 080012Google Scholar

    [21]

    Kennel C F, Engelmann F 1966 Phys. Fluids 9 2377Google Scholar

    [22]

    刘祖光 2020 硕士学位论文 (衡阳: 南华大学)

    Liu Z G 2020 M. S. Thesis (Hengyang: University of South China

    [23]

    The GENRAY Ray Tracing Code, Smirnov A P, Harvey R W https://compxco.com/Genray_manual.pdf [2003-03-17

    [24]

    Artaud J F, Imbeaux F, Garcia J, Giruzzi G, Aniel T, Basiuk V, Bécoulet A, Bourdelle C, Buravand Y, Decker J, Dumont R, Eriksson L G, Garbet X, Guirlet R, Hoang G T, Huynh P, Joffrin E, Litaudon X, Maget P, Moreau D, Nouailletas R, Pégourié B, Peysson Y, Schneider M, Urban J 2018 Nucl. Fusion 58 105001Google Scholar

    [25]

    李新霞, 李国壮, 刘洪波 2020 物理学报 69 145201Google Scholar

    Li X X, Li G Z, Liu H B 2020 Acta Phys. Sin. 69 145201Google Scholar

    [26]

    杨友磊, 胡业民, 项农 2017 物理学报 66 245202Google Scholar

    Yang Y L, Hu Y M, Xiang N 2017 Acta Phys. Sin. 66 245202Google Scholar

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出版历程
  • 收稿日期:  2023-07-01
  • 修回日期:  2023-08-11
  • 上网日期:  2023-09-12
  • 刊出日期:  2023-12-20

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