[en] There exists a regime in parameter space where a small high-field ohmically-heated tokamak may be capable of reaching thermonuclear ignition. Results of numerical simulations of the minimum ignition conditions are presented which include empirical, sawtooth, and magnetic field ripple diffusion and the effects of impurities. An ignition condition is derived and compared with the results of the numerical simulations

No abstract available

[en] The purpose of this paper is to present a compact tokamak Fusion Engineering Research Facility (FERF) concept that would allow substantial reduction in both the initial capital cost and the life cycle cost relative to a larger engineering test reactor such as the International Tokamak Reactor (INTOR). The proposed concept has emerged as a variant to the Long Pulse Ignited Test Experiment (LITE) design developed by the Massachusetts Institute of Technology and TRW as part of the US Dept. of Energy-sponsored Mission I ignition experiment studies of 1985. One of the LITE variants investigated during the studies was LITE-R3, which featured water-cooled magnets capable of steady-state operation and an inertially cooled first wall and vacuum vessel assembly. Recognizing the intrinsic potential of the LITE technology for longer pulse (20- to 30-s) operation, the design team developed several component upgrade options that would allow for longer pulses. These include: (a) replaceable first wall water coolant panels and (b) provision for active helium ash removal and impurity control. Remote maintenance issues were also addressed

[en] Brief discussions of the following topics are given: (1) current rise and preheating; (2) beam heating to ignition; (3) transition to burn; (4) burn; and (5) shutdown

[en] This letter contains a summary of recent physics results that has direct bearing on the scientific feasibility of the Riggatron reactor concept. It includes results on the effects of the buildup of impurities, magnetic field ripples, control of the burn, and the transition from ignition to reactor burn parameters

[en] With today's technology it may be possible to construct a small high-field ohmically-heated tokamak which will confine a plasma capable of supporting a self-sustaining thermonuclear reaction. Results of numerical simulations of the minimum ignition conditions are presented which include empirical, sawtooth, and magnetic field ripple diffusion and the effects of impurities. An ignition condition is derived and compared with the results of the numerical simulations

[en] For the reactor computations of MAK1 to be meaningful, the physical models must do a reasonable job of describing present day experiments. Accordingly we have set the levels of the anomalous transport coefficients to most accurately describe those experiments which involve the least extrapolation to the reactor regime. At the present time, the two most relevant experiments are the Alcator-A and the neutral-beam heated PLT. Alcator-A having the highest-values of n tau and providing data over a wide range of densities allows a good calibration of the empirical electron heat conductivity coefficients while PLT additionally gives maximum levels at which trapped-particle modes may operate consistent with the observed ion temperatures. Graphs of the agreement between MAK1 and the experiments are shown using either an empirical anomalous electron thermal conductivity or the MAK1 phenomenological model. An experimental temperature profile is shown with the corresponding MAK1 profile plotted on it

[en] The MAK1 code has been upgraded in each of the following areas: (1) numerics; (2) pellet refueling module; (3) neutral beam modules; (4) transport modules; and (5) control modules

[en] In ETF it is desired to maintain burn parameters of anti T/sub i/ approx. = to 12 keV, anti n/sub H/ approx. = to 10²⁰/m³, P/sub n/ approx. = to to 1100 MW constant over a period nominally of about 500 sec. This clearly will require some feedback control mechanism since, left to its own, the equilibrium operating-point temperature would rise to an unacceptably high value thus leading to unstable values to β, large synchrotron emission, and a rapid buildup to He ash. It has been proposed that the burn may be effectively controlled by adding ripple to the confining toroidal field. In this note we investigate this possibility coupled with maintaining the density with pellet injection

[en] We are developing a series of computer codes (MAK0, MAK1, MAK2) which realistically model the performance of tokamak reactors in 0, 1, and 2 dimensions. Versions of MAK0 and MAK1 are operational and described in this report. They solve the time evolution of the density and energy conservation equations in D-T plasmas with alphas, neutrals, and two impurity species. MAK1 solves the plasma equilibrium equation on the Lagrangian flux-coordinate grid with transport coefficients computed as surface average quantities which include Pfirsh--Schulter, neoclassical, and trapped particle effects. Plasma recycle and impurity injection are self-consistent with charged particle and neutron outflow. An average ion coronal model determines impurity charges. Major radius control and plasma scrapeoff by a limiter are modeled. These codes are applicable to a wide variety of physics or engineering studies of tokamak reactors