等離子體物理-KMAX-FRC研究報告課件

1、KMAX-FRC：The first FRC formed by in-vessel -pinch in a tandem mirror device1KMAX-FRC：The first FRC formed 2OutlineIntroductionKMAX-FRCRecent ResultSummary2OutlineIntroduction3IntroductionField Reversed Conguration3IntroductionField Reversed C4IntroductionFormation techniquesq-pinchTranslation-trappi

2、ngCollision-mergingMerging spheromaks with opposite helicitiesRotating magnetic fields (RMFs)W. T. Armstrong, R. K. Linford, J. Lipson, D. A. Platts and E. G. Sherwood, Phys. Fluids. 24, 2068 (1981).4IntroductionFormation techni5KMAX-FRC DeviceCutaway drawing of the KMAX-FRC. Its length is 9.6 m and

3、 the inner diameter of the central chamber is 1.2 m. Mirror coils are located at z= -4.5, -2.5, 2.5, and 4.5 m. Maximum mirror eld is 3600 Gauss. -pinch coils are from the z = -2.0 to -1.0 m, and z = 1.0 to 2.0 m.5KMAX-FRC DeviceCutaway drawi6KMAX DC magnetic fieldMagnetic mirror:The magnetic field

4、produced by the magnetic throat coils is axially squeezed into the initial magnetic field, a magnetic null can be generated at the corresponding location of the axis.is expected to play an important role in the confinement of the open-field-line plasma. The open-field-line plasma leads to improvemen

5、ts in the core plasma properties, including particle and energy connement.H. Gota, M. Tuszewski, E. Trask, E. Garate, M. W. Binderbauer, et al., Fusion Sci. Technol. 68, 44 (2015).6KMAX DC magnetic fieldMagnet7KMAX-FRC DeviceElectrical circuit of KMAX-FRC pulsed power system7KMAX-FRC DeviceElectrica

6、l ciHV pulse generator based on a SCR and MOSFET:8HV pulse generator Trigger voltage and current waveforms at pseudosparks ignitor(MOSFET).Repetition-rate test at 500 Hz operation. Output voltage and current of the 200 load resistor.Trigger voltage and current waveforms at pseudosparks ignitor(MOSFE

7、T).HV pulse generator based on a 9Pulsed power systemParameterUnitBias banksPI banksMain banksBank voltagekV-202040Bank capacitymF508 28 58Bank energykJ803.232Bank inductancenH3005050Bank resistancem1005050Quarter-cyclems81.253.707.15Maximum currentkA178168528Maximum magnetic fieldGauss55252016909Pu

8、lsed power systemParameterU10In-vacuum -pinch coilsThe half-angle calculated from the first to last loop is about 2.8 10In-vacuum -pinch coilsThe h11Electrode feed-through inside vacuum11Electrode feed-through insid12Pulse gas injection system12Pulse gas injection system13Recent ResultMagnetic Probe

9、sDetermining the internal magnetic field structureFlux loop Determining the excluded flux of FRC plasmaA 4-chord microwave interferometerLine integrated density Triple Langmuir probeThe electron density and temperatureFast-Framing CameraAvalanche photodiode (APD)13Recent ResultMagnetic Probes14Recen

10、t ResultMagnetic ProbesFlux loop InterferometerFast-Framing Camera/APDFast-Framing Camera/APDAPD14Recent ResultMagnetic Probes15Recent ResultA temporal magnetic field inside a single-sided FRC.Excluded flux history measured using a flux loop at z = 0.33 m.Line integrated density at r= 12.6 cm of a 4

11、-chord microwave interferometer system.Achieved stable plasma with record lifetime up to 300 ms.At present the device is operated at a relative low voltage condition and the working gas is argon.The magnetic waveform produced by -pinch current. (b) Line integrated density measured by a microwave int

12、erferometer at the mid-plane, the distance of the microwave chord to the axis is 12.6 cm. (c) Magnetic flux measured by a diamagnetic loop at z = 0.33 m. The background magnetic field strength in the central cell is 80 Gauss.15Recent ResultA temporal magn16Recent ResultThe velocity of the ejected FR

13、C plasmoid is one of the most important parameters for colliding and merging processes of FRCs. Three avalanche photodiodes (APD) were used to measure the ejection velocity of single-sided FRC plasmoid. Intervals between port to port are 1 m. The estimated FRC velocity was approximately 10 km/s. Typ

14、ical waveforms from APD (single-sided FRC).16Recent ResultThe velocity of17Recent ResultFast-Framing Camera, Phantom CV 2.8Parameters:102416 320000 fpsf=0.7 m, Aperture=1.8Colliding and merging two plasmoids poicture from camera 17Recent ResultFast-Framing Ca18Recent ResultFast-Framing Camera, Phantom CV 2.8Parameters:102416 320000 fpsf=0.7 m, Aperture=1.8Typical waveforms from camera. (a) The camera is located at z=-1 m, (b) The camera is located at the mid-plane.18Recent ResultFast-Framing Ca19Recent Result19Recent Result20Summary20Summary21Summary In the future, the main