1. 1 L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea HL-2A 2 nd Asia-Pacific Transport Working Group Meeting ELM mitigation with SMBI-CJI fuelling in HL- 2A H-mode plasmas C. Y. Chen, L. H. Yao, B.B. Feng, Z. B. Shi, W.L. Zhong, J. Cheng, D. L. Yu, X. R. Duan Southwestern Institute of Physic 2012/05/17

2. 2 nd Asia-Pacific Transport Working Group Meeting 2 Outline SMBI & CJI Fuelling deposition area ELM mitigation  ELM mitigation with SMBI  ELM mitigation with CJI Summary and discussion

3. 2 nd Asia-Pacific Transport Working Group Meeting 3 SMBI & CJI B C Solid / liquid isentrope gas P v (T) A (P 0,T 0 ) P(T) log P log T The gas expands adiabatically, the flow velocity increases and Mach number continues to increases to M>>1 in the zone of silence. The gas state changes follow the isentrope, over the saturated vapor pressure line, molecular combined together to clusters in the beam.

4. 2 nd Asia-Pacific Transport Working Group Meeting 4 SMBI & CJI Rayleigh scattering and electron fluorescence method to measure the clusters.

5. 2 nd Asia-Pacific Transport Working Group Meeting SMBI & CJI 5 ~1ms ~0.8ms Pressure: 1.65MPa Pulse duration: 2 ms Temprature: -156 ℃ Delay time: ~1 ms Pressure: 1.45 MPa Pulse duration: 2 ms Room temprature Delay time: ~ 0.8 ms

6. 2 nd Asia-Pacific Transport Working Group Meeting 6 H-mode discharge on HL-2A

7. 2 nd Asia-Pacific Transport Working Group Meeting 7 Density profile

8. 2 nd Asia-Pacific Transport Working Group Meeting 8 Deposition area of SMBI SMBI parameters for s hot 14045 (H-mode) ： P = 1.2 MPa, pulse duration 3 ms, separatrix on r = 37 cm, D particles deposited area around r = 36.5 cm 。

9. 2 nd Asia-Pacific Transport Working Group Meeting 9 Deposition area of CJI CJI could send particles to the pedestal top.

10. 2 nd Asia-Pacific Transport Working Group Meeting 10 ELM mitigation a b c Bt ： 1.4 T IP ： 150 ~ 180 kA Ne ： 1.4 ~ 2.4 ECRH ： 1 ~ 1.5 MW NBI ： 0.5 ~ 0.8 MW ELMs mitigation with SMBI (a) ， CJI (b) ， He SMBI (c).

11. 2 nd Asia-Pacific Transport Working Group Meeting 11 ELM mitigation with SMBI ~ 2-3.5 are achieved. Significant change of the ELM signal after SMBI pulse. The influence persistence time last longer as the injected particles increasing.

12. 2 nd Asia-Pacific Transport Working Group Meeting 12 ELM mitigation with CJI Multi - CJI Pressure: 1.4 MPa Duration: 2 ms Power: 1 MW NBI

13. 2 nd Asia-Pacific Transport Working Group Meeting ELM mitigation 13 The comparison of SMBI and CJI on ELM mitigation Pressure: 1.1 MPa Duration: 4 ms Room temperature Pressure: 4 MPa Duration: 0.6 ms Temperature: - 156 ℃

14. 2 nd Asia-Pacific Transport Working Group Meeting 14 ELM mitigation The heat flux at divertor plate remains the same approximately, the filaments number (2.5  ) increases by 30%. Per-ELM filament carried heart flux at the strike-point decreased 27%, 38%, 57%.

15. 2 nd Asia-Pacific Transport Working Group Meeting 15 ELM mitigation Auto-power spectrum of the particle flux measured by Langmuir probe located near the separatrix indicating that the large scale turbulence structures are significantly suppressed, CJI can trigger more small structures (ELM filament or avalanches).

16. 2 nd Asia-Pacific Transport Working Group Meeting 16 Summary and discussion CJI could inject deeper and may fuel to the pedestal top in HL-2A. Experiment results show that SMBI & CJI fuelling are able to mitigate ELM on HL-2A. CJI fuelling has the potential to control ELM on larger fusion device. Larger cluster deeper injection? CJI benefit from deeper injection for ELM mitigation? CJI fuelling have the potential to control ELM on larger fusion devices?

17. 2 nd Asia-Pacific Transport Working Group Meeting 17 Thank you for your attention!