Plasma Sheath Velocity and Pinch Phenomenal Measurements in TPF-II Plasma Focus Device Arlee Tamman PE wave : Center of Excellence in Plasma Science and Electromagnetic Wave Walailak University, THAILAND
Plasma Research in Walailak University 1.5 cm 8 cm Low Pressure Plasma Atmospheric Pressure Plasma
The Fusion Research in Thailand Simulations of ITER and Tokamak Sirindhorn International Institute of Technology Prof. Thawatchai Onjun Plasma Focus Device - UNU/ICTP Device : Chulalongkorn University Prof. Rattachat Mongkolnavin - TPF-I : Thammasat University Prof. Nopporn Poolyarat - TPF-II : Walailak University Prof. Mudtrolep Nisoa Phuket TPF : Thailand Plasma Focus 3
Presentation Outline Introduction to Plasma Focus Experiment Setup System Inductance Designing Short circuit test Plasma Parameter Estimation Measurement System Result Conclusion 4
Discharge Unit 23rd IAEA Technical Meeting on the Research Using Small Fusion Devices Introduction to Plasma Focus device - Plasma focus n = 10 24 10 26 m 3 Anode Cathode Radial Phase Axial Acceleration Phase Responding Waveform Breakdown Phase Triggering Unit Power Supply Spark Gap Capacitor Power Source Plasma Focus Equivalent Circuit 5
JxB Introduction to Plasma Focus device - RLC Circuit responding Pinch Time, t= T/4 B I Spark Gap The pinch phase must occur at the equal time with the maximum current. Capacitor 6
Experimental Setup: System Inductance Capacitor: 40 nh Coaxial (RG218): 252 nh/m Target : 125 nh Current Collector : 19 nh TDI3-200k: 20 nh Designing Inductance Static inductance (79 nh) Capacitor : 40 nh (Fix) Current Collector : 19 nh Spark Gap (TDI3-200k) : 20 nh (from NX3: TDI1-150K) Varying inductance (368 nh) 1 m of Coaxial Cable : 252 nh/line Connector : 116 nh/line (8 line of Coaxial -> 368/8 = 46 nh) 7
Experimental Setup - Current Collector Design (Target : 20 nh) 8
Experimental Setup - Short Circuit test Operating parameter Voltage: 3 kv Coaxial Lines: 2, 4, 8 L R I Short Circuit Plate 9
Experimental Setup Short Circuit Test 10 Loop of Rogowski Coil 19.9 ± 0.3 nh 15.8 ± 0.2 nh 13.48 ± 0.08 nh Number of Connector: 2 Number of Connector: 4 Number of Connector: 8 L 0 = 330 ± 10 nh L 0 = 211 ± 5 nh L 0 = 153 ± 2 nh 10
Experimental Setup Short Circuit Test System Inductance (n=8) - Design : 125 nh - Device : 153 nh L 0 = 93 + 476/n L static =93 nh L connector =476 nh Device: 153 nh L capacitor =40 nh Coaxial Cable = 252 nh L collector =19 nh Connector = 224 nh (Design = 116 nh) L Spark Gap =34 nh (Design : 20 nh) 11
Experimental Setup Plasma Parameter Estimation Device : L 0 = 153 nh T/4 = 3 ms 23rd IAEA Technical Meeting on the Research Using Small Fusion Devices Operating Parameters C 0 : 30 mf R 0 : 20 mohm V 0 : 10 kv Gas Type : Argon Pressure : 1.2 Torr Model Parameters F m = 0.039 F c = 0.78 F mr = 0.17 F cr = 1 I max =110 ka 12
Experimental Setup Capacitor Charging Voltage Storage Energy Inductance Operating Gas Electrode : 30 mf : 10 kv : 1.5 kj : 153 nh Argon ( 1.2 torr ) - Cathode Radial : 2.50 cm - Anode Radial : 1.25 cm - Length : 8.5 cm Lee Model Maximum Current : 110 ka Pinch Duration : 15.46 ns Pinch Temperature : 178-247 ev = 80 ka/(cm torr 1/2 ). 13
Experimental Setup Glass Viewer Fiber Optic 14
Experimental Setup Dental X-ray film (30 40 mm) 15
Results: Pinch Percentages Charging Voltage : 10 kv Charging Voltage : 12 kv 16
Results: Sheath Velocity Charging Voltage : 10 kv 17
Results: X-Ray 50 Shot 30 Shot Dental X-Ray Machine 20 Shot 10 Shot TPF-II 0.6 torr 10 kv of Charging Voltage 18
Cu-I 576.97 Cu-III 610.08 Ar-I 750.38 23rd IAEA Technical Meeting on the Research Using Small Fusion Devices Ar-II 1020.39 Ar-II 1030.56 Ar-II 1044.05 Results: Optical Emission Spectroscopy #964-NF No Focus 19
Conclusion The pinch phase is confirmed by the current waveform and X-ray photography. Estimate parameters of the TPF-II are 110 ka of maximum current, 15.46 ns of pinch duration and 200 ev of the pinch temperature. Light emission of the pinch phase show the line of Ar-I, Ar-II, Cu-I, Cu-II and Cu-III Future Work PIN Diodes for X-Ray Diagnostics. Faraday Cup for Ion Beam Diagnostics. Application of Ion Beam for Gemstone Modification.
Acknowledges - A scholarship was supported by Human Resource Development in Science Project (Science Achievement Scholarship of Thailand, SAST) - Government Annual Research Budget through Thammasat University. - High Voltage Power Supply was Supported by Chulalongkorn University and Chang Mail University 21
INTERNATIONAL CONFERENCE ON PLASMA SCIENCE AND APPLICATIONS ICPSA 2017 23 25 OCTOBER 2017 WALAILAK UNIVERSITY, THAILAND
Ar-II 1020.39 Cu-III 610.08 Ar-II 1044.05 Cu-I 576.97 Ar-II 1030.56 Experimental Setup : Optical Emission Spectroscopy Line Wavelength (nm) Intensity (a.u.) Cu I 576.975 3013.47 Cu III 610.087 895.47 Cu II 662.4292 2107.72 Cu II 786.058 1592.97 Cu I 925.680 689.97 Cu I 921.375 584.97 Cu I 953.03 927.72 Cu II 1 002.2969 772.72 Line Wavelength (nm) Intensity (a.u.) Ar II 531.611 1213.72 Ar I 588.2624 1079.72 Ar II 620.646 1204.72 Ar II 655.772 3998.72 Ar II 705.4993 1584.47 Ar I 737.2118 2176.47 Ar I 750.3869 2395.47 Ar I 762.8882 2681.97 Ar II 792.735 2508.22 Ar I 800.6157 1839.47 Ar I 810.3693 3368.72 Ar II 825.9521 1125.22 Ar I 840.8210 1573.97 Ar II 971.377 1552.72 Ar II 1 020.3928 1622.97 Ar II 1 030.56350 2055.47 Ar II 1 044.05079 2117.72 No Focus 23
Experimental Setup : Rogowski Coil and Magnetic Probe - Plasma focus OES X-Ray Film Magnetic Probe Targ et 4 Ch. Scope 2 GSa/s 2 Ch. Scope 1 GSa/s Current Probe 2 Ch. Scope 1 GSa/s OES Scope Current Probe Triggering Unit Power Supply Spark Gap Capacitor HV Probe 24
Experimental Setup : HV Probe and Magnetic Probe Magnetic Probe V.4 1000x High Voltage Probe 25
Experimental Setup :Current and Voltage 3/2558 1/2559 26
Experimental Setup : HV Probe and X-Ray Film Current X-Ray 27
Experimental Setup : HV Probe and Magnetic Probe Magnetic Probe V.4 1000x High Voltage Probe 28
Current Coil
Introduction to Plasma Focus device - Plasma focus phase : Axial Acceleration Phase Optimized gas pressure REF: Bernard, A., et all. (1998). Scientific status of plasma focus research. J. Moscow. Phys. Soc., 8, 93 170. 30
Introduction to Plasma Focus device - RLC Circuit responding RLC Circuit I t = V 0 ωl e R 2L t sin ωt = I 0 e R 2L t sin ωt 31
db/dt B (a.u.) 32
Experimental Setup Problem 33
Experimental Setup Problem Solving 34