Globus-M Diagnostic Equipment
Advanced Diagnostics Array for Spherical Tokamak Globus-M
Tech Area / Field
- FUS-PLA/Plasma Physics/Fusion
- PHY-OPL/Optics and Lasers/Physics
8 Project completed
Senior Project Manager
Russian Academy of Sciences / Physical Technical Institute, Russia, St Petersburg
- TRINITI, Russia, Moscow reg., Troitsk\nNIIEFA Efremov, Russia, St Petersburg\nLOMO Enterprise, Russia, St Petersburg\nVNIIEF, Russia, N. Novgorod reg., Sarov
- University of Wisconsin-Madison / College of Engineering, Nuclear and Engineering Physics, USA, WI, Madison\nHelsinki University of Technology, Finland, Helsinki\nOak Ridge National Laboratory, USA, TN, Oak Ridge\nVTT Energy / Nuclear Energy, Finland, Helsinki\nUniversität Stuttgart / Institut für Plasmaforschung, Germany, Stuttgart\nENEA, Italy, Frascati\nColumbia University / Applied Physics Department, USA, New York
Project summaryThe novel research equipment complex-spherical tokamak Clobus-M, including additional systems is under construction now in the frames of ISTC projects 159, 159B and 159C. The power supply reconstruction is going on, the experimental hall construction is completed. The project will be completed in the first quarter of 1998. New type of plasma device nominated for the spherical tokamak concept evaluation will be created as a result. Spherical tokamak plasma researches are of interest for fundamental plasma physics and its application to controlled fusion program. Spherical tokamak represents nowadays a promising prototype for volumetric fusion neutrons source. Also under discussion is the concept of spherical tokamak fusion power plant, which might help in minimizing its size and cost. The novel plasma properties in spherical tokamaks require novel approach in diagnostics system development.
The aim of the project is research, design and construction of advanced diagnostics array (second turn diagnostics set-up) for the Globus-M spherical tokamak experiments. Four diagnostics set-up with high temporal and spatial resolution are included into the advanced diagnostics array.
- Novel multipulse Nd -glass laser (15-20 pulses during plasma discharge) with high output energy in every pulse (10-20 J) will be developed as a basis of diagnostics. Specially designed spectrometer set together with avalanche photodetectors operating in the near infrared waverange will provide detailed quasicontinuous measurements of electron temperature and density profiles.
- Scanning pulse Radar reflectometer with carrier frequency sweeping are to be developed for the first time in the world. It will give detailed electron density profile (up to 10 spatial points) with good temporal resolution (-10 (msec). Novelly designed fast frequency sweeping scheme with successive frequency multiplication by 4 together with additional low-frequency channel will overlap the frequency range 0.4 - 4 ґ 1019 m-3. Such approach will save the number of channels in compassion with fixed frequency channels and minimize the device cost without scarifying of performance.
- The fast videocamera with novel principal of exposure control in each frame will be designed and constructed for plasma cross-section monitoring in the visible spectrum range. The proposed exposure control by recording light flux changes during one frame wiU significantly (up to 102) increase the dynamic range of the device. The spatial resolution of the plasma column shape and position of plasma edge will be significantly increased.
- The system of spectrometric pin-hole SXR cameras, each containing 3-4 detector array with different filters will provide tomografic image of plasma cross-section with microsecond scale temporal resolution and electron temperature measurements along different chords in millisecond scale range.
The constructed and tested diagnostics equipment which will be created in the frames of the project together with other diagnostics of Globus-M tokamak allow to measure plasma parameters, study plasma energy balance, analyze plasma column shape and position, study different magnetic configurations and plasma column stability in different phases of ohmic and auxiliary plasma heating. The advantage of proposed diagnostics array is high temporal and spatial resolution, which makes attractive the usage of this diagnostics array on other conventional and spherical tokamaks. The minimizing of diagnostics cost is achieved by the novel technical approach development and by designing of new, improved devices on the basis of non-expensive prototypes.
Potential role of foreign collaborators
Princeton University, Oak-Ridge National laboratory US, Culham laboratory U.K. and Helsinki University of technology Finland are foreign collaborators of ISTC project #159 Globus-M tokamak. During numerous workshops and meetings as well as during bilateral exchange a number of useful discussions, reviews and decisions were made which had a direct impact on improvement of the device performance. We plan to conserve the active way of communications with collaborators in the frames of the current project.
Also we hope that experience of collaborators in plasma diagnostics and spherical tokamak experiments makes possible to use it during Globus-M diagnostics set-up development. We also plan to convince colleagues from IPP, Germany and ENEA, Italy to collaborate the project.
Important project result is the opportunity to start full-scale experimental program of spherical tokamak plasma physics investigation on Globus-M tokamak. This could sufficiently improve the situation with the project funding, as many collaborators (outside and inside SIC) will participate in joint experimental program, contributing funds and equipment.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.