Research

SPARC

My role on has been focused on contributing to the physics basis and design of the SPARC tokamak. A next step high field compact tokamak funded by Commonwealth Fusion System and being developed in partnership with the MIT Plasma Science and Fusion Center. As part of this position, I have led the initial design up to the conceptual design review of:

  • Gas heating and cooling system - a closed gas loop that flows through the device to both cool between experiments and heat for vacuum conditioning.
  • Wall conditioning systems - A suite a wall conditioning systems are being deployed on SPARC for improved vacuum quality, plasma performance, and tritium recovery.
  • Vacuum pumping systems - to provide ultra high vacuum inside the tokamak and also close the fuel cycle between the device and gas delivery systems.
  • Temperature sensors - a suite of temperature sensors in-vessel that provide a machine protection function as well as improve our physics understanding of the overall power balance in the design.
  • Langmuir probes - a suite of langmuir probes are being installed to help improve our physics understand of heat and particle fluxes to the walls of the device

I performed the pre-conceptual scoping and continue to contribute to the design of:

  • Plasma facing components - the primary armor that protects the machine from the miniature sun contained within.
  • Magnetic equilibriums - Scoping of coil placement and currents required to meet the device mission.
  • Gas fueling - Estimates of gas injection locations, and throughputs.
  • Vacuum vessel - the primary container for the plasma, I have contributed to the thermal and structural analysis of the system.
  • Copper magnetic coils - Contributing to defining the system requirements, design and thermal/structural analysis.

In addition, I have worked on a number of projects:

  • Led the development of an integrated thermal model for the device.
  • Design and executed a series of high heat flux testing of plasma facing component materials.
  • Was part of the operations team for the first large bore 20 Tesla High Temperature Superconductor Magnet.

Thesis

The thesis submitted to the Department of Nuclear Science and Engineering at the Massachusetts Institute of Technology as part of the requirements for the degree of Doctor of Philosophy in Applied Plasma Physics can be found here.

Publications

Kuang, A. Q., Ballinger, S., Brunner, D., Canik, J., Creely, A. J., Gray, T., Greenwald, M., Hughes, J. W., Irby, J., LaBombard, B., Lipschultz, B., Lore, J. D., Reinke, M. L., Terry, J. L., Umanksy, M., Whyte, D.G, Wukitch, S. and the SPARC Team (2020). Divertor heat flux challenge and mitigation in SPARC. Journal of Plasma Physics, 86(5), 865860505. doi:10.1017/S0022377820001117

Kuang, A. Q., LaBombard, B., Brunner, D., Garcia, O.E., Kube, R., Theodorsen, A. (2019). Plasma fluctuations in the scrape-off layer and at the divertor target in Alcator C-Mod and their relationship to divertor collisionality and density shoulder formation. Nuclear Materials and Energy. 19. 295-299. DOI: 10.1016/j.nme.2019.02.038

Kuang, A. Q., Cao, N. M., Creely, A. J., Dennett, C. A., Hecla, J., Hoffman, H., … Whyte, D. G. (2018). Conceptual design study for heat exhaust management in the ARC fusion pilot plant. Fusion Engineering and Design. 137, 221-242. DOI: j.fusengdes.2018.09.007

Kuang, A. Q., Brunner, D., LaBombard, B., Leccacorvi, R., & Vieira, R. (2018). The flush-mounted rail Langmuir probe array designed for the Alcator C-Mod vertical target plate divertor. Review of Scientific Instruments. 89, 043512. DOI: 10.1063/1.5023905

Kuang, A. Q., Brunner, D., LaBombard, B., Leccacorvi, R., & Vieira, R. (2017). Design and operation of a high-heat flux, flush-mounted “rail”Langmuir probe array on Alcator C-Mod. Nuclear Materials and Energy, 12, 1231–1235. DOI: 10.1016/j.nme.2016.08.014

Kuang, A., Sridhar, A., Garven, J., Gutschmidt, S., Rodgers, G. W., Chase, J. G., Gavin, H. P., Nigbor, R. L., MacRae, G. A. (2014). Christchurch Women's Hospital: Performance Analysis of the Base-Isolation System during the Series of Canterbury Earthquakes 2011-2012. Journal of Performance of Constructed Facilities, 30(4), 04015096. DOI: 10.1061/(ASCE)CF.1943-5509.0000846

Matthews, A., Terry, J., Baek, S.G., Hughes, J.W., Kuang, A.Q., LaBombard, B., Miller, M.A., Stotler, D., Reiter, D., Zholobenko, W., Goto, M. (2022) Deep modelling of plasma and neutral fluctuations from gas puff turbelence imaging. Review of Scientific Instruments, 93, 063504. DOI: 10.1063/5.0088216

Ballinger, S., Brunner, D., Hubbard, A.E., Hughes, J.W., Kuang, A.Q., LaBombard, B., Terry, J.L., White, A. (2022) Dependence of the Boundary Heat Flux Width on Core and Edge Profiles in Alcator C-Mod. Nuclear Fusion, 62.7, 076020. DOI:10.1088/1741-4326/ac637c

Rodriguez-Fernandez, P., Creely, A.J., Greenwald, M.J., Brunner, D., Ballinger, S.B., Chrobak, C.P., ... Yuryev, D.V. (2022) Overview of the SPARC physics basis towards the exploration of burning-plasma regimes in high-field, compact tokamaks. Nuclear Fusion, 62, 042003. DOI: 10.1088/1741-4326/ac1654

McCarthy, W., Golfinopoulos, T., Woller, K. B., Vincent, C., Kuang, A., LaBombard, B. (2021). First application of a digital mirror Langmuir probe for real-time plasma diagnosis. Review of Scientific Instruments, 92, 103502. DOI: 10.1063/5.0057318

Ballinger, S.B., Kuang, A.Q., Umansky, M.V., Brunner, D., Canik, J.M., Greenwald, M., Lore, J.D., LaBombard, B., Terry, J.L., Wigram, M. (2021). Simulation of the SPARC plasma boundary with the UEDGE code. Nuclear Fusion, 61, 086014. DOI: 10.1088/1741-4326/ac0c2f

Creely, A., Greenwald, M., Ballinger, S., Brunner, D., Canik, J., Doody, J., . . . Zhu, J. (2020). Overview of the SPARC tokamak. Journal of Plasma Physics, 86(5), 865860502. doi:10.1017/S0022377820001257

Hughes, J. W., Howard, N. T., Rodriguez-Fernandez, P., Creely, A. J., Kuang, A. Q., Snyder, P. B., Wilks, T. M., Sweeney, R., Greenwald, M. (2020). Projections of H-mode access and edge pedestal in the SPARC tokamak. Journal of Plasma Physics, 86(5), 865860504. doi:10.1017/S0022377820001300

Creely, A.J., Milanese, L.M., Tolman, E.A., Irby, J.H., Ballinger, S.B., Frank, S. Kuang, A.Q., Linehan, B.L., McCarthy, W., Montes, K.J., and others, Design study of a combined interferometer and polarimeter for a high-field, compact tokamak. Physics of Plasmas 27, no. 4 (2020): 042516. DOI: 10.1063/1.5142638.

Umansky, M. V., LaBombard, B., Brunner, D., Golfinopoulos, T., Kuang, A. Q., Rensink, M. E., Terry, J. L., Wigram, M. K. R., and Whyte, D. G. (2019).Study of passively stable, fully detached divertor plasma regimes attained in innovative long-legged divertor configurations. Nuclear Fusion, 60, 016004 DOI: 10.1088/1741-4326/ab46f4

Wigram, M. K. R., LaBombard, B., Umansky, M. V., Kuang, A. Q., Golfinopoulos, T., Terry, J. L., Brunner, D., Rensink, M. E.,  Ridgers, C. P., and Whyte, D. G. (2019). Performance assessment of long-legged tightly-baffled divertor geometries in the ARC reactor concept. Nuclear Fusion, 59, 106052 DOI: 10.1088/1741-4326/ab394f

Vincent, C., McCarthy, W. M., Golfinopoulos, T., LaBombard, B., Sharples, R., Lovell, J., Naylor, G., Hall, S., Harrison, J., and Kuang, A. Q. (2019). The digital mirror Langmuir probe: Field programmable gate array implementation of real-time Langmuir probe biasing. Review of Scientific Instruments, 90, 083504. DOI: 10.1063/1.5109834

Tinguely, R.A., Rosenthal, A., Simpson, R., Ballinger, S.B., Creely, A.J., Frank, S., Kuang, A.Q., Linehan, B.L., McCarthy, W., Milanese, L.M., and others, Neutron diagnostics for the physics of a high-field, compact, Q≥1 tokamak. Fusion Engineering and Design, 143 (2019): 212-225. DOI:10.1016/j.fusengdes.2019.03.148

Reinke, M.L., Brunner, D., Golfinopoulos, T., Hubbard, A.E., Hughes, J.W., Kuang, A.Q., LaBombard, B., Marmar, E.S., Mumgaard, B., Terry, J.L. and Lore, J.D., (2019). Radiative heat exhaust in Alcator C-Mod I-mode plasmas. Nuclear Fusion. 59. 046018. DOI: 10.1088/1741-4326/ab04cf

Kube, R., Garcia, O.E., Theodorsen, A., Kuang, A.Q., LaBombard, B., Terry, J.L., Brunner, D. (2019). Statistical properties of the plasma fluctuations and turbulent cross-field fluxes in the outboard mid-plane scrape-off layer of Alcator C-Mod. Nuclear Materials and Energy, 18, 193-200. DOI: 10.1016/j.nme.2018.11.021

Brunner, D., LaBombard, B., Kuang, A.Q., Terry, J. (2018). High-resolution heat flux width measurements at reactor-level magnetic fields and observation of a unified width scaling across confinement regimes in the Alcator C-Mod tokamak. Nuclear Fusion. DOI: 10.1088/1741-4326/aad0d6

Brunner, D., Kuang, A.Q., LaBombard, B., Terry, J. (2018). The dependence of divertor power sharing on magnetic flux balance in near double-null configurations on Alcator C-Mod. Nuclear Fusion (58). DOI: 10.1088/1741-4326/aac006

Kube, R., Garcia, O. E., Theodorsen, A., Brunner, D., Kuang, A. Q., LaBombard, B., Terry, J. L. (2018). Intermittent electron density and temperature fluctuations and associated fluxes in the Alcator C-Mod scrape-off layer. Plasma Physics and Controlled Fusion. 60(6). DOI: 10.1088/1361-6587/aab726.

Wigram, M., LaBombard, B., Umansky, M. V., Kuang, A. Q., Brunner, D., Terry, J. L., Golfinopoulos, T., Rensink, M. E., Whyte, D. G. (2018). UEDGE modelling of detached divertor operation for long-leg divertor geometries in ARC. Contributions to Plasma Physics, 58(6-8), 791-797. DOI: 10.1002/ctpp.201700178.

McCarthy, W., LaBombard, B., Brunner, D., & Kuang, A. Q. (2018). An experimental assessment of methods used to compute secondary electron emission yield for tungsten and molybdenum electrodes based on exposure to Alcator C-Mod scrape-off layer plasmas. Plasma Physics and Controlled Fusion. DOI: 10.1088/1361-6587/aaa51c

Brunner, D., Kuang, A. Q., LaBombard, B., & Burke, W. (2017). Linear servomotor probe drive system with real-time self-adaptive position control for the Alcator C-Mod tokamak. Review of Scientific Instruments, 88(7), 73501. DOI: 10.1063/1.4990043

Brunner, D., Wolfe, S. M., LaBombard, B., Kuang, A. Q., Lipschultz, B., Reinke, M. L., … Terry, J. L. (2017). Surface heat flux feedback controlled impurity seeding experiments with Alcator C-Mod’s high-Z vertical target plate divertor: performance, limitations and implications for fusion power reactors. Nuclear Fusion, 57(8), 86030. DOI: 10.1088/1741-4326/aa7923

LaBombard, B., Kuang, A. Q., Brunner, D., Faust, I., Mumgaard, R., Reinke, M. L., … Chilenski, M. (2017). Impurity screening behavior of the high-field side scrape-off layer in near-double- null configurations: prospect for mitigating plasma–material interactions on RF actuators and first-wall components. Nuclear Fusion, 57(7), 76021. DOI: 10.1088/1741-4326/aa6dd2

LaBombard, B., Kuang, A. Q., Brunner, D., Faust, I., Mumgaard, R., Reinke, M. L., … Chilenski, M. (2017). High-field side scrape-off layer investigation: Plasma profiles and impurity screening behavior in near-double- null configurations. Nuclear Materials and Energy, 12, 139–147. DOI: 10.1016/j.nme.2016.10.006

Tinguely, R. A., Granetz, R. S., Berg, A., Kuang, A. Q., Brunner, D., & LaBombard, B. (2017). High-resolution disruption halo current measurements using Langmuir probes in Alcator C-Mod. Nuclear Fusion, 58(1), 16005. DOI: 10.1088/1741-4326/aa8fa6

Brunner, D., Burke, W., Kuang, A. Q., LaBombard, B., Lipschultz, B., & Wolfe, S. (2016). Feedback system for divertor impurity seeding based on real-time measurements of surface heat flux in the Alcator C-Mod tokamak. Review of Scientific Instruments, 87(2), 23504. DOI: 10.1063/1.4941047

Faust, I. C., Brunner, D., LaBombard, B., Parker, R. R., Terry, J. L., Whyte, D. G., … Hughes, J. W. (2016). Lower hybrid wave edge power loss quantification on the Alcator C-Mod tokamak. Physics of Plasmas, 23(5), 56115. DOI: 10.1063/1.4951736

Zhou, C., Chase, J. G., Rodgers, G. W., Kuang, A., Gutschmidt, S., Xu, C. (2015). Performance evaluation of CWH base isolated building during two major earthquakes in Christchurch. Bulletin of the New Zealand Society for Earthquake Engineering, 48(4), 264. EID: 2-s2.0-85019986266

Sridhar, A., Kuang, A., Garven, J., Gutschmidt, S., Chase, J. G., Gavin, H. P., Nigbor, R. L., Rodgers, G. W., MacRae, G. A. (2014). Christchurch women's hospital: Analysis of measured earthquake data during the 2011-2012 Christchurch earthquakes. Earthquake Spectra, 30(1), 383. DOI: 10.1193/021513EQS027M

Presentations

Kuang, A. Q., Cao, N. M., Creely, A. J., Dennett, C. A., Hecla, J., Hoffman, H., … Whyte, D. G. (2017). Implementation of a long leg X-point target divertor in the ARC fusion pilot
plant. At 59th Annual Meeting of the APS Division of Plasma Physics, Milwaukee, Wisconsin.

Kuang, A. Q., LaBombard, B., & Brunner, D. (2016). Complications with flush-mounted probe analysis beyond sheath-expansion. At 58th Annual Meeting of the APS Division of Plasma Physics, San Jose, California.

Kuang, A. Q., Brunner, D., LaBombard, B., Leccacorvi, R., & Vieira, R. (2016). Design and operation of a high-heat flux, flush-mounted “rail” Langmuir probe array on Alcator C-Mod, At 22nd International Conference on Plasma Surface Interactions in Controlled Fusion Devices, Rome, Italy.

Kuang, A. Q., Brunner, D., LaBombard, B., Leccacorvi, R., & Vieira, R. (2015). First operation of a high-heat flux, flush mounted``rail’’Langmuir probe array on Alcator C-Mod. At 57th Annual Meeting of the APS Division of Plasma Physics, Savannah, Georgia.

 

Dennett, C. A., Cao, N. M., Creely, A. J., Hecla, J., Hoffman, H., Kuang, A. Q., … Whyte, D. G. (2017). Conceptual design study for heat exhaust management in the ARC fusion pilot plant. At 59th Annual Meeting of the APS Division of Plasma Physics, Milwaukee, Wisconsin..

Garcia, O. E., Kuang, A. Q., Brunner, D., LaBombard, B., & Kube, R. (2017). Fluctuations measured by flush mounted versus proud divertor Langmuir probes-why are they different? At 59th Annual Meeting of the APS Division of Plasma Physics, Milwaukee, Wisconsin..

LaBombard, B., Brunner, D., Kuang, A. Q., McCarthy, W., & Terry, J. L. (2017). The effect of feedback-controlled divertor nitrogen seeding on the boundary plasma and power exhaust channel width in Alcator C-Mod. At 59th Annual Meeting of the APS Division of Plasma Physics, Milwaukee, Wisconsin..

Brunner, D., LaBombard, B., Kuang, A. Q., Terry, J. L., Alcator C-Mod Team (2017). Boundary plasma heat flux width measurements for poloidal magnetic fields above 1 Tesla in the Alcator C-Mod tokamak. At 59th Annual Meeting of the APS Division of Plasma Physics, Milwaukee, Wisconsin..

LaBombard, B., Umansky, M., Brunner, D., Kuang, A. Q., Marmar, E., Wallace, G., … Wukitch, S. (2016). Examining Innovative Divertor and Main Chamber Options for a National Divertor Test Tokamak.  At 58th Annual Meeting of the APS Division of Plasma Physics, San Jose, California..

Brunner, D., LaBombard, B., Kuang, A. Q., Terry, J. L., Mumgaard, B., Wolfe, S. (2016). Divertor conditions near double null in Alcator C-Mod. At 58th Annual Meeting of the APS Division of Plasma Physics, San Jose, California..

LaBombard, B., Kuang, A. Q., Brunner, D., Mumgaard, R., Terry, J. L.,...Reinke, M. (2015). High-field side scrape-off layer investigation: scaling of the power e-folding width and impurity screening behavior in near-double null configuration. At 57th Annual Meeting of the APS Division of Plasma Physics, Savannah, Georgia.

Brunner, D., Kuang, A. Q., LaBombard, B., & Burke, W. (2015). Development of a reciprocating probe servomotor control system with real-time feedback on plasma position for the Alcator C-Mod tokamak. At 57th Annual Meeting of the APS Division of Plasma Physics, Savannah, Georgia.