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Status of tandem mirror theory

Description: This report contains the text and slides used for the review talk on tandem mirror theory presented at the meeting of the Division of Plasma Physics, A.P.S., Boston, MA, November 12-16, 1979. Topics covered include classical confinement, equilibria, MHD- and micro-stability, radial transport, and thermal barriers.
Date: December 12, 1979
Creator: Baldwin, D.E.
Partner: UNT Libraries Government Documents Department

Compact 5 x 10/sup 12/ AMP/SEC rail-gun pulser for a laser plasma shutter

Description: We have developed a rail-gun plasma source to produce a plasma of 10/sup 12/cm/sup -3/ particle density and project it with a velocity of 3.9 cm/..mu..s. This device will be used in a output spatial filter of Nova to project a critical density plasma across an optical beam path and block laser retroreflected light. The object of this paper is to describe the design of a pulser appropriate to the Shiva laser fusion facility, and to describe the preliminary design of a higher current prototype pulser for Nova the laser fusion research facility under construction at Lawrence Livermore Laboratory.
Date: June 12, 1979
Creator: Bradley, L.P.; Orham, E.L. & Stowers, I.F.
Partner: UNT Libraries Government Documents Department

MFTF supervisory control and diagnostics system hardware

Description: The Supervisory Control and Diagnostics System (SCDS) for the Mirror Fusion Test Facility (MFTF) is a multiprocessor minicomputer system designed so that for most single-point failures, the hardware may be quickly reconfigured to provide continued operation of the experiment. The system is made up of nine Perkin-Elmer computers - a mixture of 8/32's and 7/32's. Each computer has ports on a shared memory system consisting of two independent shared memory modules. Each processor can signal other processors through hardware external to the shared memory. The system communicates with the Local Control and Instrumentation System, which consists of approximately 65 microprocessors. Each of the six system processors has facilities for communicating with a group of microprocessors; the groups consist of from four to 24 microprocessors. There are hardware switches so that if an SCDS processor communicating with a group of microprocessors fails, another SCDS processor takes over the communication.
Date: November 12, 1979
Creator: Butner, D.N.
Partner: UNT Libraries Government Documents Department

Applying a Compensated Pulsed Alternator to a flashlamp load for NOVA

Description: The Compensated Pulsed Alternator (CPA) is a large rotating machine that will convert mechanical, rotationally stored energy into a single electrical impulse of very high power. It is being optimized for driving flashlamps in the very large NOVA Nd:glass laser system. The machine is a rotary flux compression device, and for maximum performance, it requires start-up current. We report upon a circuit that will provide this current and that will also assist in triggering the flashlamps. This circuit has been tested with a 200 kilojoule capacitor bank and it is now being tested with a small 200 kilojoule CPA. Large Nove-size machines will require output energies in excess of 5 megajoules. We also present empirically tested formulae that will assist in matching the Nova flashlamp load to any given size CPA machine.
Date: June 12, 1979
Creator: Carder, B.M. & Merritt, B.T.
Partner: UNT Libraries Government Documents Department

Balanced, parallel operation of flashlamps

Description: A new energy store, the Compensated Pulsed Alternator (CPA), promises to be a cost effective substitute for capacitors to drive flashlamps that pump large Nd:glass lasers. Because the CPA is large and discrete, it will be necessary that it drive many parallel flashlamp circuits, presenting a problem in equal current distribution. Current division to +- 20% between parallel flashlamps has been achieved, but this is marginal for laser pumping. A method is presented here that provides equal current sharing to about 1%, and it includes fused protection against short circuit faults. The method was tested with eight parallel circuits, including both open-circuit and short-circuit fault tests.
Date: June 12, 1979
Creator: Carder, B.M. & Merritt, B.T.
Partner: UNT Libraries Government Documents Department

Date base management system for the MFTF

Description: The data base management system (DBMS) for the Mirror Fusion Test Facility (MFTF) is described as relational in nature and distributed across the nine computers of the supervisory control and diagnostics system. This paper deals with a reentrant runtime package of routines that are used to access data items, the data structures to support the runtime package, and some of the utilities in support of the DBMS.
Date: November 12, 1979
Creator: Choy, J.H. & Wade, J.A.
Partner: UNT Libraries Government Documents Department

MFTF plasma diagnostics data acquisition system

Description: The initial goal of the Data Acquisition System (DAS) is to control 11 instruments chosen as the startup diagnostic set and to collect, process, and display the data that these instruments produce. These instruments are described in a paper by Stan Thomas, et. al. entitled ''MFTF Plasma Diagnostics System.'' The DAS must be modular and flexible enough to allow upgrades in the quantity of data taken by an instrument, and also to allow new instruments to be added to the system. This is particularly necessary to support a research project where needs and requirements may change rapidly as a result of experimental findings. Typically, the startup configuration of the diagnostic instruments will contain only a fraction of the planned detectors, and produce approximately one half the data that the expanded version is designed to generate. Expansion of the system will occur in fiscal year 1982.
Date: November 12, 1979
Creator: Davis, G.E. & Coffield, F.E.
Partner: UNT Libraries Government Documents Department

Sustaining neutral beam power supply system for the Mirror Fusion Test Facility

Description: A fixed-price procurement contract for $24.9 million was awarded to Aydin Energy Division, Palo Alto, CA, for the design, manufacture, installation, and acceptance testing of the sustaining neutral beam power supply system (SNBPSS). This system is scheduled for completion in early 1981 and will provide the conditioned power for the 24 neutral beam source modules. Each of the 24 power supply sets will provide the accel potential of 80 kV at 88 A, the arc power, the filament power, and the suppressor power for its associated neutral beam source module.
Date: November 12, 1979
Creator: Eckard, R.D. & Van Ness, H.W.
Partner: UNT Libraries Government Documents Department

Test and evaluation of the BBC CQK 200-4 modulator tube for the MFTF sustaining neutral beam power supply system

Description: The BBC CQK 200-4 Tube was tested by Aydin at LLL, to confirm that it would switch 90 kV after conducting 88 amperes for 30 seconds. The CQK 200-4 is a recent modification of the CQK 200-3, an Rf transmitter tube designed for continuous loading, to increase the anode hold-off voltage to 150 kV. During the design life of the tube it will be subjected to 10/sup 5/ to 10/sup 6/ cyclic thermal loads. Two concerns are that (1) during the 30 second high current load, the screen grid may have excessive dissipation causing a loss of control of the tube, and (2) the cyclic temperature-induced stresses in the anode may cause fatigue failures that will reduce the tube's useful life. The first concern was addressed by performing full scale tests at the LLL test facility.
Date: November 12, 1979
Creator: Eckard, R.D.; Van Ness, H.W. & Hesselgrave, D.
Partner: UNT Libraries Government Documents Department

Near and long term pulse power requirements for laser driven inertial confinement fusion

Description: At the Lawrence Livermore Laboraory, major emphasis has been placed upon the development of large, ND:glass laser systems in order to address the basic physics issues associated with light driven fusion targets. A parallel program is directed toward the development of lasers which exhibit higher efficiencies and shorter wavelengths and are thus more suitable as drivers for fusion power plants. This paper discusses the pulse power technology which has been developed to meet the near and far term needs of the laser fusion program at Livermore.
Date: June 12, 1979
Creator: Gagnon, W. L.
Partner: UNT Libraries Government Documents Department

Nova: a high energy laser system

Description: This review briefly describes the laser system, spatial filter, computer control system, and the 46 cm disk amplifier. (MOW)
Date: October 12, 1979
Creator: Godwin, R.O.
Partner: UNT Libraries Government Documents Department

Development of a Plasma Streaming System for the Mirror Fusion Test Facility

Description: The Plasma Streaming System (PSS) is an essential portion of the Mirror Fusion Test Facility (MFTF), scheduled for completion in October 1981. The PSS will develop a plasma density of at least 2 x 10/sup 12/ particles/cm/sup 3/ at the MFTF magnet centerline by injecting particles along the field lines. The plasma will have a midplane plasma radius as large as 40 cm with variable plasma particle energy and beam geometry. Minimum amounts of impurities will be injected, with emphasis on minimizing high Z materials. Each of the 60 PSS units will consist of a gun magnet assembly (GMA) and a power supply. Each GMA consists of a plasma streaming gun, a pulse magnet that provides variable beam shaping, and a fast reaction pulse gas valve.
Date: November 12, 1979
Creator: Holdsworth, T.; Clark, R.N.; McCotter, R.E.; Rossow, T.L. & Cruz, G.E.
Partner: UNT Libraries Government Documents Department

Overview of the MFTF electrical systems

Description: The Mirror Fusion Test Facility, scheduled for completion in October 1981, will contain a complex, state-of-the-art array of electrical and electronics equipment valued at over 60 M$. Three injector systems will be employed to initiate and sustain the MFTF deuterium plasma. A plasma streaming system and a startup neutron beam system will be used to establish a target plasma. A sustaining neutral beam system will be used to fuel and sustain the MFTF plasma for 0.5 s. Additional power supply systems required on MFTF include two magnet power supplies with quench protection circuitry for powering the superconducting YIN/YANG magnet pair and eight 10 KHz power supplies for powering the Ti gettering system. Due to the complexity, physical size, and multiple systems of MFTF, a distributed, hierarchial, computer control and instrumentation system will be used. Color graphic, touch-panel, control consoles will provide the man-machine interface. The MFTF will have the capability of conducting an experiment every five minutes.
Date: November 12, 1979
Creator: Lindquist, W.B.; Eckard, R.D.; Holdsworth, T.; Mooney, L.J.; Moyer, D.R.; Peterson, R.L. et al.
Partner: UNT Libraries Government Documents Department

Computer code determination of tolerable accel current and voltage limits during startup of an 80 kV MFTF sustaining neutral beam source

Description: We have used a Lawrence Livermore Laboratory (LLL) version of the WOLF ion source extractor design computer code to determine tolerable accel current and voltage limits during startup of a prototype 80 kV Mirror Fusion Test Facility (MFTF) sustaining neutral beam source. Arc current limits are also estimated. The source extractor has gaps of 0.236, 0.721, and 0.155 cm. The effective ion mass is 2.77 AMU. The measured optimum accel current density is 0.266 A/cm/sup 2/. The gradient grid electrode runs at 5/6 V/sub a/ (accel voltage). The suppressor electrode voltage is zero for V/sub a/ < 3 kV and -3 kV for V/sub a/ greater than or equal to 3 kV. The accel current density for optimum beam divergence is obtained for 1 less than or equal to V/sub a/ less than or equal to 80 kV, as are the beam divergence and emittance.
Date: November 12, 1979
Creator: Mayhall, D.J. & Eckard, R.D.
Partner: UNT Libraries Government Documents Department

Digital simulation of the MFTF power supply system using EMTP

Description: The power supply system for MFTF will consist of twenty-four sets of accel, arc, and filament power supplies. The system will be fed from a common source and split into sets of two for the accel supplies and sets of four for the arc and filament supplies. This paper describes the simulation of this system and the EMTP code that was used. Interactions between power supplies during turn on that are due to common system impedances are studied, and a description of Transient Analysis of Control Systems (TACS) control is presented. The system harmonic content found by EMTP is discussed. The paper concludes with a brief discussion of an accel crowbar simulation.
Date: November 12, 1979
Creator: Mihalka, A.M.
Partner: UNT Libraries Government Documents Department

Overview of MFTF supervisory control and diagnostics system software

Description: The Mirror Fusion Test Facility (MFTF) at the Lawrence Livermore Laboratory (LLL) is currently the largest mirror fusion research project in the world. Its Control and Diagnostics System is handled by a distributed computer network consisting of nine Interdata minicomputer systems and about 65 microprocessors. One of the design requirements is tolerance of single-point failure. If one of the computer systems becomes inoperative, the experiment can still be carried out, although the system responsiveness to operator command may be degraded. In a normal experiment cycle, the researcher can examine the result of the previous experiment, change any control parameter, fire a shot, collect four million bytes of diagnostics data, perform intershot analysis, and have the result presented - all within five minutes. The software approach adopted for the Supervisory Control and Diagnostics System features chief programmer teams and structured programming. Pascal is the standard programming language in this project.
Date: November 12, 1979
Creator: Ng, W.C.
Partner: UNT Libraries Government Documents Department

MFTF exception handling system

Description: In the design of large experimental control systems, a major concern is ensuring that operators are quickly alerted to emergency or other exceptional conditions and that they are provided with sufficient information to respond adequately. This paper describes how the MFTF exception handling system satisfies these requirements. Conceptually exceptions are divided into one of two classes. Those which affect command status by producing an abort or suspend condition and those which fall into a softer notification category of report only or operator acknowledgement requirement. Additionally, an operator may choose to accept an exception condition as operational, or turn off monitoring for sensors determined to be malfunctioning. Control panels and displays used in operator response to exceptions are described.
Date: November 12, 1979
Creator: Nowell, D.M. & Bridgeman, G.D.
Partner: UNT Libraries Government Documents Department

Beta II plasma-gun mechanical design and construction

Description: The magnetized coaxial plasma gun (located on the east end of the Beta II facility at the Lawrence Livermore Laboratory) will be used to test a new method of initiating a field reversed mirror plasma. The field-reversed mirror is expected to improve the mirror-fusion reactor by enhancing the ratio of fusion power to injected power. This paper concentrates on the mechanical design and construction of the magnetized coaxial plasma gun and also discusses the diagnostic devices necessary to demonstrate the formation of field-reversed rings.
Date: November 12, 1979
Creator: Pedrotti, Laurence; Deis, Gary; Wong, Robert; Calderon, Manuel; Chargin, Anthony & Garner, Donald
Partner: UNT Libraries Government Documents Department

Fabrication of 0. 5-inch diameter FBR mixed oxide fuel pellets

Description: Large diameter (0.535 inch) mixed oxide fuel pellets for Fast Breeder Reactor application were successfully fabricated by the cold-press-and-sinter technique. Enriched UO/sub 2/, PuO/sub 2/-UO/sub 2/, and PuO/sub 2/-ThO/sub 2/ compositions were fabricated into nominally 90% theoretical density pellets for the UO/sub 2/ and PuO/sub 2/-UO/sub 2/ compositions, and 88% and 93% T.D. for the PuO/sub 2/-ThO/sub 2/ compositions. Some processing adjustments were required to achieve satisfactory pellet quality and density. Furnace heating rate was reduced from 200 to 50/sup 0/C/h for the organic binder burnout cycle for the large, 0.535-inch diameter pellets to eliminate pellet cracking during sintering. Additional preslugging steps and die wall lubrication during pressing were used to eliminate pressing cracks in the PuO/sub 2/-ThO/sub 2/ pellets.
Date: September 12, 1979
Creator: Rasmussen, D.E.; Benecke, M.W. & McCord, R.B.
Partner: UNT Libraries Government Documents Department

Neutral beam control systems for the Tandem Mirror Experiment

Description: The Tandem Mirror Experiment (TMX) is presently developing the technology and approaches which will be used in larger fusion systems. This paper describes some of the designs which were used in creating the control system for the TMX neutral beams. To create a system of controls that would work near these large, rapid switching current sources required a mixture of different technologies: fiberoptic data transmission, printed circuit and wirewrap techniques, etc.
Date: November 12, 1979
Creator: Ross, R.I.
Partner: UNT Libraries Government Documents Department

Heavy quark jets

Description: The present understanding of heavy quark fragmentation is reviewed, and the expected behaviors of heavy quark jets is discussed. Included are short-distance versus long-distance parts of fragmentation, fragmentation dynamics at long distances, universal hadronization in rapidity plot, the heavy quark as a sizzling fireball, quantum chromodynamics ladder summation in the region of K/sub T/ < ..lambda.., and the relevance or irrelevance to super high energy experiment. 6 references. (JFP)
Date: November 12, 1979
Creator: Suzuki, M.
Partner: UNT Libraries Government Documents Department

Magnetic confinement in plasmas in nuclear devices

Description: The main emphasis of the magnetic fusion energy research program today lies in the development of two types of confinement schemes: magnetic mirrors and tokamaks. Experimental programs for both of these confinement schemes have shown steady progress toward achieving fusion power breakeven. The scaling of the current machines to a reactor operating regime and newly developed methods for plasma heating will very likely produce power breakeven within the next decade. Predictions are that the efficiency in a fusion power plant should exceed 32%.
Date: July 12, 1979
Creator: Tull, C.G.
Partner: UNT Libraries Government Documents Department

Control and diagnostic data structures for the MFTF

Description: A Data Base Management System (DBMS) is being written as an integral part of the Supervisory Control and Diagnostics System (SCDS) of programs for control of the Mirror Fusion Test Facility (MFTF). The data upon which the DBMS operates consist of control values and evaluative information required for facilities control, along with control values and disgnostic data acquired as a result of each MFTF shot. The user interface to the DBMS essentially consists of two views: a computer program interface called the Program Level Interface (PLI) and a stand-alone interactive program called the Query Level Interface to support terminal-based queries. This paper deals specifically with the data structure capabilities from the viewpoint of the PLI user.
Date: November 12, 1979
Creator: Wade, J.A. & Choy, J.H.
Partner: UNT Libraries Government Documents Department