Massive Gas Injection Valve Development for NSTX-U

Raman, R.; Plunkett, G. J.; Way, W.-S.

doi:10.11578/1366479

Title: Massive Gas Injection Valve Development for NSTX-U

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Abstract

NSTX-U research will offer new insight by studying gas assimilation efficiencies for MGI injection from different poloidal locations using identical gas injection systems. In support of this activity, an electromagnetic MGI valve has been built and tested. The valve operates by repelling two conductive disks due to eddy currents induced on them by a rapidly changing magnetic field created by a pancake disk solenoid positioned beneath the circular disk attached to a piston. The current is driven in opposite directions in the two solenoids, which creates a cancelling torque when the valve is operated in an ambient magnetic field, as would be required in a tokamak installation. The valve does not use ferromagnetic materials. Results from the operation of the valve, including tests conducted in 1 T external magnetic fields, are described. The pressure rise in the test chamber is measured directly using a fast time response baratron gauge. At a plenum pressure of just 1.38 MPa (~200 psig), the valve injects 27 Pa.m^3 (~200 Torr.L) of nitrogen with a pressure rise time of 3 ms.

Authors:

Raman, R.; Plunkett, G. J.; Way, W.-S.

Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Publication Date:: Sun May 01 00:00:00 EDT 2016

DOE Contract Number:: AC02-09CH11466

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; MGI Disruption mitigation Electromagnetic Eddy current

Keywords:: MGI Disruption mitigation Electromagnetic Eddy current

OSTI Identifier:: 1366479

DOI:: https://doi.org/10.11578/1366479

Citation Formats


                    Raman, R., Plunkett, G. J., and Way, W.-S. Massive Gas Injection Valve Development for NSTX-U.  United States: N. p., 2016. 
        Web.  doi:10.11578/1366479.

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                    Raman, R., Plunkett, G. J., & Way, W.-S. Massive Gas Injection Valve Development for NSTX-U.  United States.  doi:https://doi.org/10.11578/1366479

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                    Raman, R., Plunkett, G. J., and Way, W.-S. 2016.  
"Massive Gas Injection Valve Development for NSTX-U".  United States.  doi:https://doi.org/10.11578/1366479.  https://www.osti.gov/servlets/purl/1366479. Pub date:Sun May 01 00:00:00 EDT 2016

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@article{osti_1366479,

  title        = {Massive Gas Injection Valve Development for NSTX-U},

  author       = {Raman, R. and Plunkett, G. J. and Way, W.-S.},

  abstractNote = {NSTX-U research will offer new insight by studying gas assimilation efficiencies for MGI injection from different poloidal locations using identical gas injection systems. In support of this activity, an electromagnetic MGI valve has been built and tested. The valve operates by repelling two conductive disks due to eddy currents induced on them by a rapidly changing magnetic field created by a pancake disk solenoid positioned beneath the circular disk attached to a piston. The current is driven in opposite directions in the two solenoids, which creates a cancelling torque when the valve is operated in an ambient magnetic field, as would be required in a tokamak installation. The valve does not use ferromagnetic materials. Results from the operation of the valve, including tests conducted in 1 T external magnetic fields, are described. The pressure rise in the test chamber is measured directly using a fast time response baratron gauge. At a plenum pressure of just 1.38 MPa (~200 psig), the valve injects 27 Pa.m^3 (~200 Torr.L) of nitrogen with a pressure rise time of 3 ms.},

  doi          = {10.11578/1366479},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sun May 01 00:00:00 EDT 2016},

  month        = {Sun May 01 00:00:00 EDT 2016}

}

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DOI: https://doi.org/10.11578/1366479

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