Then, several sets of equilibrium conditions during the tokamak operation are found to observe the changes of poloidal field currents with the passing of operation time step, and the basic stability problems related with the magnetic field structure is also considered. As most of the data to run TSC consists of conductor positions, the graphical interface is especially appropriate. The spectrum of the excited Alfven waves is determined using a one-dimensional MHD code. The transient time and AC analysis of the RF generator performance with antenna loading are discussed.
The exponential growth in energy consumption has led to a renewed interest in the development of alternatives to fossil fuels. Between the unconventional resources that may help to meet this energy demand, nuclear fusion has arisen as a promising source, which has given way to an unprecedented interest in solving the different control problems existing in nuclear fusion reactors such as Tokamaks. The aim of this manuscript is to show how one of the most popular codes used to simulate the performance of Tokamaks , the Automatic System For Transport Analysis ASTRA code , can be integrated into the Matlab-Simulink tool in order to make easier and more comfortable the development of suitable controllers for Tokamaks.
As a demonstrative case study to show the feasibility and the goodness of the proposed ASTRA-Matlab integration, a modified anti-windup Proportional Integral Derivative PID -based controller for the loop voltage of a Tokamak has been implemented. The integration achieved represents an original and innovative work in the Tokamak control area and it provides new possibilities for the development and application of advanced control schemes to the standardized and widely extended ASTRA transport code for Tokamaks. A computer code , DSTAR, has recently been developed to quantify the surface erosion and induced forces that can occur during major tokamak plasma disruptions.
The DSTAR code development effort has been accomplished by coupling a recently developed free boundary tokamak plasma transport computational model with other models developed to predict impurity transport and radiation, and the electromagnetic and thermal dynamic response of vacuum vessel components.
The LIUQE code adopts a computationally efficient method to solve this problem, based on an iterative solution of the Poisson equation coupled with a linear parametrisation of the plasma current density. This algorithm is unstable against vertical gross motion of the plasma column for elongated shapes and its application to highly shaped plasmas on TCV requires a particular treatment of this instability. TCV's continuous vacuum vessel has a low resistance designed to enhance passive stabilisation of the vertical position. The eddy currents in the vacuum vessel have a sizeable influence on the equilibrium reconstruction and must be taken into account.
The design and operating principle of the CXRS diagnostics are described. The method of averaging the CXRS spectra over several shots, which is used at the T tokamak to increase the signal-to-noise ratio, is described. The approximation of the spectrum by a set of Gaussian components is used to identify the active CXRS line in the measured spectrum. The time behavior of the ion temperature profile in different ohmic heating modes is studied. Experimental data from the CXRS diagnostics at T substantially contribute to the implementation of physical programs of studies on heat and particle transport in tokamak plasmas and investigation of geodesic acoustic mode properties.
Modular pump limiter systems for large tokamaks. A pump limiter can provide the needed exhaust capability by removing a small percentage of the particles, which would otherwise be recycled. A third type of pump limiter is a system that consists of several modules and exhibits performance different from that of a single module. To take advantage of the flexibility of a modular pump limiter system in a high-power, long-pulse device, the power load must be distributed among a number of modules. Because each added module changes the performance of all the others, a set of design criteria must be defined for the overall limiter system.
The design parameters for the modules are then determined from the system requirements for particle and power removal. Design criteria and parameters are presented, and the impact on module design of the state of the art in engineering technology is discussed. The relationship between modules are considered from the standpoint of flux coverage and shadowing effects.
The results are applied to the Tore Supra tokamak. A preliminary conceptual design for the Tore Supra pump limiter system is discussed, and the design parameters of the limiter modules are presented. The ion cyclotron IC system in conjunction with an 8-MW neutral beam and a 1. The IC system will deliver 6 MW of RF power to the plasma in the 25 to 60 MHz frequency range, using a single four-strap antenna mounted in a midplane port. The phasing between current straps in the antenna will be adjustable quickly during operation to provide the capability of changing the current-drive efficiency.
This report describes the design of the IC system hardware: the electrical characteristics of the antenna and the matching system , the requirements on the power sources, and electrical analyses of the launcher. High performance operational limits of tokamak and helical systems.
The plasma operational boundaries of tokamak and helical systems are surveyed and compared with each other. Global confinement scaling laws are similar and gyro-Bohm like, however, local transport process is different due to sawtooth oscillations in tokamaks and ripple transport loss in helical systems. As for stability limits, achievable tokamak beta is explained by ideal or resistive MHD theories. On the other hand, beta values obtained so far in helical system are beyond ideal Mercier mode limits.
Density limits in tokamak are often related to the coupling between radiation collapse and disruptive MHD instabilities, but the slow radiation collapse is dominant in the helical system. The pulse length of both tokamak and helical systems is on the order of hours in small machines, and the longer-pulsed good-confinement plasma operations compatible with radiative divertors are anticipated in both systems in the future.
The production of a lithium deposition system using commercially available components is discussed. This system is intended to provide a fresh lithium wall coating between discharges in a tokamak. A test system consisting of a lithium evaporator and a deposition monitor has been designed and constructed to investigate deposition rates and coverage.
A Thermionics 3kW e-gun is used to rapidly evaporate small amounts of solid lithium. Initial results from the test system will be presented. Tokamak power systems studies at ANL. A number of advances in plasma physics and engineering promise to greatly improve the reactor prospects of tokamaks. The key to high beta operation with low toroidal current lies in utilizing second stability regime equilibria with the required current distributions produced by an appropriate selection of wave driver frequencies and power spectra.
The ray tracing and current drive calculation is self-consistent with the actual magnetic fields produced in the plasma. In addition to matching desirable high-beta equilibria, this method is capable of producing a large variety of new equilibria, many of which look attractive. The impurity control activities in TPSS have emphasized the self-pumping concept as applied to using the entire first wall or ''slot'' limiters. The blanket design effort has emphasized liquid metal and Flibe concepts.
Overall, there exists a number of major design improvements which will substantially improve the attractiveness of tokamak reactors. We present gyrokinetic neoclassical simulations of tokamak plasmas with a self-consistent electric field using a fully nonlinear full- f continuum code TEMPEST in a circular geometry. A set of gyrokinetic equations are discretized on a five-dimensional computational grid in phase space.
The present implementation is a method of lines approach where the phase-space derivatives are discretized with finite differences, and implicit backward differencing formulas are used to advance the system in time. The neoclassical electric field is obtained by solving the gyrokinetic Poisson equation with self-consistent poloidal variation. With a four-dimensional psi,theta,micro version of the TEMPEST code , we compute the radial particle and heat fluxes, the geodesic-acoustic mode, and the development of the neoclassical electric field, which we compare with neoclassical theory using a Lorentz collision model.
The present work provides a numerical scheme for self-consistently studying important dynamical aspects of neoclassical transport and electric field in toroidal magnetic fusion devices. A Toroidally Symmetric Plasma Simulation code for design of position and shape control on tokamak plasmas. The analyses of three-dimensional eddy currents on the conducting components around the plasma and the two-dimensional magneto-hydrodynamic MHD equilibrium are taken into account in this code.
The code can analyze the plasma position and shape control during the minor disruption in which the deformation of plasma is not negligible. A one-dimensional transport code for the simulation of D-T burning tokamak plasma. A one-dimensional transport code for D-T burning tokamak plasma has been developed, which simulates the spatial behavior of fuel ions D, T , alpha particles, impurities, temperatures of ions and electrons, plasma current, neutrals, heating of alpha and injected beam particles.
The basic transport equations are represented by one generalized equation so that the improvement of models and the addition of new equations may be easily made. A model of burn control using a variable toroidal field ripple is employed. This report describes in detail the simulation model, numerical method and the usage of the code.
Some typical examples to which the code has been applied are presented. Dhanani, Kalpesh; Raval, D. Hydrogen gas feeding with piezoelectric valve is used in the SST-1 plasma experiments. This paper will present the technical development and the results of the gas fuelling system of SST Continuous, saturation, and discontinuous tokamak plasma vertical position control systems. Mitrishkin, Yuri V. An unstable dynamic element obtained by the identification of plasma-physical DINA code was used as the plasma model. The simplest static feedback state space control law was synthesized as a linear combination of signals accessible to physical measurements, namely the plasma vertical displacement, the current, and the voltage in a horizontal field coil, to solve the pole placement problem for a closed-loop system.
Only one system distinctive parameter was used to optimize the performance of the feedback system , viz. A first-order inertial unit was used as the rectifier model in the feedback. A system with a complete rectifier model was investigated as well. A system with the voltage inverter model and static linear controller was brought into a sliding mode. As this takes place, real time delays were taken into account in the discontinuous voltage inverter model. The comparison of the linear and sliding mode systems showed that the linear system enjoyed an essentially wider range of the plant model parameters where the feedback system was stable.
System assessment of helical reactors in comparison with tokamaks. Higher-temperature plasma operation is required in tokamak reactors to increase bootstrap current fraction and to reduce current-drive CD power. In helical systems , lower-temperature operation is feasible and desirable to reduce helical ripple transport. The capital cost of helical reactor is rather high, however, the cost of electricity COE is almost same as that of tokamak reactor because of smaller re-circulation power no CD power and less-frequent blanket replacement lower neutron wall loading.
A predictive transport modeling code for ICRF-heated tokamaks. Details of the physics contained in the RAZE code are examined in section 3. Sample results from the package follow in section 4, with concluding remarks and a discussion of possible improvements to the package discussed in section 5.
MHD stability analyses of a tokamak plasma by time-dependent codes. The MHD properties of a tokamak plasma are investigated by using time evolutional codes. As for the ideal MHD modes we have analyzed the external modes including the positional instability. Linear and nonlinear ideal MHD codes have been developed. Effects of the toroidicity and conducting shell on the external kink mode are studied minutely by the linear code.
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A new rezoning algorithm is devised and it is successfully applied to express numerically the axisymmetric plasma perturbation in a cylindrical geometry. As for the resistive MHD modes we have developed nonlinear codes on the basis of the reduced set of the resistive MHD equations. By using the codes we have studied the major disruption processes and properties of the low n resistive modes. We have found that the effects of toroidicity and finite poloidal beta are very important.
Considering the above conclusion we propose a new scenario of the initiation of the major disruption. The computer code described is used to study ripple beam injection into a tokamak plasma. The collisionless guiding center equations of motion are integrated to find the orbits of single particles in realistic magnetic fields for ripple injection. In order to determine if the ripple is detrimental to the plasma, the magnetic flux surfaces are constructed by integration of the field line equations.
The numerical techniques are described, and use of the code is outlined. A program listing is provided, and the results of sample cases are presented. A numerical code for simulation of plasma transport in Tokamaks. Plasmator is a flexible monodimensional numerical code for plasma transport in Tokamaks of circular cross-section, it allows neutral particle transport and impurity effects. The code leaves a total freedom in the analytical form of transport coefficients. Hron, M. An important issue of the operation is the safety of the personnel and machine protection against faults, presented in this contribution.
The personnel protection is based on a restricted access into the experimental hall during the operation of potentially dangerous systems. On top of this, a check of the whole experimental area by the operator is enforced before the hall enclosure. A hardware interlock then interprets the experimental hall status and controls the operation of key systems accordingly. The permit for operation is granted and the real status of the systems is reported by hard wired potential less contacts.
Its programming is done using language Simple v. Second site of personnel protection system is created on PC where runs a. This signals are displayed on a screen of the PC in real-time, this way the GUI provides visualization of the controlled process. Except for this fact the operator is informed about the status of the system and individual subsystems on a PC via an operator's panel.
Further we will describe the machine protection which uses similar system for checking conditions for the start of a shot. Fast key processes which have to be checked during the shot are. Comparison benchmark between tokamak simulation code and TokSys for Chinese Fusion Engineering Test Reactor vertical displacement control design. Vertical displacement event VDE is a big challenge to the existing tokamak equipment and that being designed. The tokamak simulation code TSC is a free boundary time-dependent axisymmetric tokamak simulation code developed in PPPL, which advances the MHD equations describing the evolution of the plasma in a rectangular domain.ipdwew0030atl2.public.registeredsite.com/491663-best-smartphone-locate.php
tokamak systems code: Topics by efohivyqet.tk
The electromagnetic interactions between the surrounding conductor circuits and the plasma are solved self-consistently. The TokSys code is a generic modeling and simulation environment developed in GA. Its RZIP model treats the plasma as a fixed spatial distribution of currents which couple with the surrounding conductors through circuit equations. It is shown that with the same inputs, the results from these two codes conform with each other.
Filterscope diagnostic system on EAST tokamak. On EAST Experimental Advanced Superconducting Tokamak , a filterscope diagnostic system has been mounted to observe the line emission and visible bremsstrahlung emission in plasma from discharge campaign of Furthermore, multi-channel signals at up to kHz sampling rates can be digitized simultaneously.
The wavelength covers He II The new developed filterscope system was operating during the EAST fall experimental campaign and several types ELMs has been observed. A specified-profile, global analysis code has been developed to evaluate the performance of fusion reactor designs. Both steady-state and time-dependent calculations are carried out; the results of the former can be used in defining the parameters of the latter, if desired.
In the steady-state analysis, the performance is computed at a density and temperature chosen to be consistent with input limits e. The calculation can be made at either the intersection of the two limits or at the point of optimum performance as the density and temperature are varied along the limiting boundaries. Two measures of performance are available for this purpose: the ignition margin or the confinement level required to achieve a prescribed ignition margin.
The time-dependent calculation can be configured to yield either the evolution of plasma energy as a function of time or, via an iteration scheme, the amount of auxiliary power required to achieve a desired final plasma energy. New applications of Equinox code for real-time plasma equilibrium and profile reconstruction for tokamaks. Recent development of real-time equilibrium code Equinox using a fixed-point algorithm allow major plasma magnetic parameters to be identified in real-time, using rigorous analytical method.
The code relies on the boundary flux code providing magnetic flux values on the first wall of vacuum vessel. By means of least-square minimization of differences between magnetic field obtained from previous solution and the next measurements the code identifies the source term of the non-linear Grad-Shafranov equation. The strict use of analytical equations together with a flexible algorithm offers an opportunity to include new measurements into stable magnetic equilibrium code and compare the results directly between several tokamaks while maintaining the same physical model i.
The successful implementation of this equilibrium code for JET and Tore Supra has already been published. In this paper, we show the preliminary results of predictive runs of the Equinox code using the ITER geometry. Because the real-time control experiments of plasma profile at JET using the code has been shown unstable when using magnetic and polarimetric measurements that could be indirectly translated into accuracy vs robustness tradeoff , we plan an outline of the algorithm that will allow us to further constrain the plasma current profile using the central value of pressure of the plasma in real-time in order to better define the poloidal beta this constraint is not necessary with purely magnetic equilibrium.
Bosak, K. Dieudonne, 06 - Nice France ; Joffrin, E.
International Conference on Magnet Technology
Diagnostics systems for the TBR-E tokamak. A general view of the several diagnostics systems proposed for the TBR-E tokamak is given. The requirements for the measurements of the plasma produced parameters are described. Special attention is given for diagnostics used to investigate new physical issues on a low aspect ratio tokamak such as TBR-E. The SASSYS LMFBR systems analysis code is being developed mainly to analyze the behavior of the shut-down heat-removal system and the consequences of failures in the system , although it is also capable of analyzing a wide range of transients, from mild operational transients through more severe transients leading to sodium boiling in the core and possible melting of clad and fuel.
The code includes a detailed SAS4A multi-channel core treatment plus a general thermal-hydraulic treatment of the primary and intermediate heat-transport loops and the steam generators. The code is fast running: usually faster than real time. The core density and temperature profiles are joined to the flux-surface average profiles from the 2D code sufficiently inside the magnetic separatrix, at a flux surface on which the edge profiles are approximately constant.
In the present version of the code , the deuterium density and electron and ion temperatures are coupled. The electron density is determined by imposing quasi-neutrality, both in the core and in the edge. The model allows the core-edge coupling of multiple ion densities while retaining a single temperature corresponding to the equilibration value for the all ion species. This work will focus on the simulation of the L-H transition, coupling a single ion species deuterium and the two electron and ion temperatures. Applications to the modeling of ITER ignition scenarios are also discussed.
This will involve coupling a second density species the thermal alphas , bringing the total number of coupled variables up to four. Finally, the progress in evolving the magnetic geometry is discussed. Recent improvements for code speed-up are also presented. Tokamak power system studies at ANL. The ray tracing and current drive calculation is self-consistent with the actual magnetic fields they produce in the plasma. System studies were performed to determine the sensitivity of hybrid and superconducting toroidal field TF coil system options to maximum field at the TF coil and to field enhancement due to resistive insert coils.
The results indicate that for TFCX with no minimum wall loading specified, a design point chosen solely on the basis of cost would likely be in the low-field region of design space where the cost advantage of hybrids is least apparent. However, as the desired neutron wall loading increases, the hybrid option suggests an increasing cost advantage over the all-superconducting option; this cost advantage is countered by increased complexity in design -- particularly in assembly and maintenance.
However, as the desired neutron wall loading increases, the hybrid option suggests an increasing cost advantage over the all-superconducting option; this cost advantage is countered by increased complexity in design - particularly in assembly and maintenance. Wang, Y. Martin; Xia, T. One challenge in long-pulse and high performance tokamak operation is to control the edge localized modes ELMs to reduce the transient heat load on plasma facing components. Minute-scale discharges in H-mode have been achieved repeatedly on Experimental Advanced Superconducting Tokamak EAST since the campaign and understanding the characteristics of the ELMs in these discharges can be helpful for effective ELM control in long-pulse discharges.
The kinetic profile diagnostics recently developed on EAST make it possible to perform the pedestal stability analysis quantitatively. The ideal linear stability results show that the ELM is dominated by toroidal mode number n around 10—15 and the most unstable mode structure is mainly localized in the steep pressure gradient region, which is consistent with experimental results. Two important features of EAST tokamak in the long-pulse discharge are presented by comparison with other tokamaks , including a wider pedestal correlated with the poloidal pedestal beta and a smaller inverse aspect ratio and their effects on the pedestal stability are discussed.
To predict the particle and heat controllability in the divertor of tokamak reactors such as ITER and to optimize the divertor design, comprehensive simulations by integrated modelling with taking in various physical processes are indispensable. The code development is originally carried out since physics models can be verified quickly and flexibly under the circumstance of close collaboration with JT team. Combination of the SOLDOR and NEUT2D was completed, which has the features such as 1 high-resolution oscillation-free scheme in solving fluid equations, 2 neutral transport calculation under the fine meshes, 3 success in reduction of MC noise, 4 optimization on the massive parallel computer, etc.
It is found that the chemically sputtered carbon at the dome causes the radiation peaking near the X-point.
The performance of divertor pumping in JTU is evaluated from the particle balances. We also present the divertor designing of JTSA, which is the modification program of JTU to establish high beta steady-state operation. Technical diagnosis system for EAST tokamak. Those status parameters include temperature of different positions of main components, resistance of each superconducting SC coils, joint resistance of SC coils and high-temperature superconducting HTS current leads, strain of cold-quality components endured force, and displacement and current of toroidal field TF coils in EAST device, which are analog input signals.
In addition there are still some analog and digital output signals. And how to protect the SC magnet system during each plasma discharging is presented with data of temperature of coolant inlet and outlet of SC coils and feeders and cases of the TF coils and temperature in the upper and middle and bottom of the TF coil case. During construction of the TDS primary difficulties come from installation of Lakeshore Cernox temperature sensors, strain measurement of central solenoid coils support legs and installation of co-wound voltage sensors for quench detection.
While during operation since the first commissioning big challenges are from temperature measurement changes in current leads and quench detection of PF coils. Those difficulties in both stages are introduced which are key to make the TDS reliable. Meanwhile analysis of experimental data like temperature as a back up to testify quench occurrence and stress on vacuum vessel thermal shield and vacuum vessel have also been discussed. Microinstabilities in weak density gradient tokamak systems. A prominent characteristic of auxiliary-heated tokamak discharges which exhibit improved ''H-mode type'' confinement properties is that their density profiles tend to be much flatter over most of the plasma radius.
Depsite this favorable trend, it is emphasized here that, even in the limit of zero density gradient, low-frequency microinstabilities can persist due to the nonzero temperature gradient. Design parameters of Tokamak -7 system. Superconducting windings for the main magnetic field of Tokamak -7 are discussed. The parameters of this facility are based on the use of commercially available superconducting materials for fields up to 80 kOe. Experimental parameters are described. Magnet systems for ''Bean-Shaped'' tokamak. Jassby, D.
If located in the bore of the TF coils, then maintenance of the pushing coils may be impossible, and the interlocking coils may prevent reactor modularity. If located outside, the required pushing-coil current may be unacceptably large. This dilemma is overcome with a unique TF coil design in which the inboard leg is bent outward in the form of an arc. The pushing coils are housed in the midplane indentation of this arc, just outside the TF coils but adequately close to the plasma.
The arched coil transfers forces to the top and bottom legs, where it can be reacted by a clamp structure if necessary. This technique would allow demountable joints to be placed near the inoard leg for copper TF coils. Another design approach to the pushing coils is to use liquid Li or Na as the conductor and coolant. The liquid metal ''coils'' can be placed immediately adjacent to the plasma, giving optimal control of the plasma shape with minimal coil current, although modularity of the reactor may have to be surrendered.
Dokuka, V. In order to provide efficient performance of tokamaks with vertically elongated plasma position, control systems for limited and diverted plasma configuration are required. The accuracy, stability, speed of response, and reliability of plasma position control as well as plasma shape and current control depend on the performance of the control system.
Therefore, the problem of the development of such systems is an important and actual task in modern tokamaks. In this study, the measured signals from the magnetic loops and Rogowski coils are used to reconstruct the plasma equilibrium, for which linear models in small deviations are constructed. The testing of the developed systems applied to the DINA code with Heaviside step functions have revealed the complex dynamics of plasma magnetic configurations. Being close to the bifurcation point in the parameter space of unstable plasma has made it possible to detect an abrupt change in the X-point position from the top to the bottom and vice versa.
Development of the methods for reconstruction of plasma magnetic configurations and experience in designing plasma control systems with feedback for tokamaks provided an opportunity to synthesize new digital controllers for plasma vertical and horizontal position stabilization. It also allowed us to test the synthesized digital controllers in the closed loop of the control system with the DINA code as a nonlinear model of plasma. Revised SRAC code system. Since the publication of JAERI in for the preliminary version of the SRAC code system , a number of additions and modifications to the functions have been made to establish an overall neutronics code system.
Major points are 1 addition of JENDL-2 version of data library, 2 a direct treatment of doubly heterogeneous effect on resonance absorption, 3 a generalized Dancoff factor, 4 a cell calculation based on the fixed boundary source problem, 5 the corresponding edit required for experimental analysis and reactor design, 6 a perturbation theory calculation for reactivity change, 7 an auxiliary code for core burnup and fuel management, etc. The present report comprises a documentation of CASINO, a simulation code developed as a means for the study of high energy charged particles in an axisymmetric Tokamak.
The background of the need for such a numerical tool is presented. In the description of the numerical model used for the orbit integration, the method using constants of motion, the Lao-Hirsman geometry for the flux surfaces and a method for reducing the necessary number of particles is elucidated. A brief outline of the calculational sequence is given as a flow chart.
The essential routines and functions as well as the common blocks are briefly described. The input and output routines are shown. Finally the documentation is completed by a short discussion of possible extensions of the code and a test case. Data processing system for spectroscopy at Novillo Tokamak. Taking as basis some proposed methodologies by software engineering it was designed and developed a data processing system coming from the diagnostic equipment by spectroscopy, for the study of plasma impurities, during the cleaning discharges.
The data were obtained starting from files type text and processed for their subsequently graphic presentation. Cryogenic system design for a compact tokamak reactor. The cryogenic system for this reactor must meet unusual and new requirements. Unusually high heat loads kW at 4. Also, large variations in the cryogenics loads occur over short periods of time because of the pulsed nature of some of the operating scenarios.
This paper describes a workable cryogenic system design for a compact tokamak reactor such as ITER. A design analysis is presented dealing with a system that handles transient loads, coil quenches, reactor cool-down and the effect of variations in helium-supply temperatures on the cryogenic stability of the coils.
It operates on a distributed system based on personal computers and has a driver-based hierarchical structure. Since KDAS can be dynamically composed of any number of available computers, and the hardware-dependent codes can be thoroughly separated into external drivers, it exhibits excellent system performance flexibility and extensibility and can optimize various user needs. With these useful and convenient features, it can be applied to any computerized experiment, especially to fusion-related research. The system design and features are discussed in detail.
Distributed digital real-time control system for TCV tokamak. Le, H. The system is designed to be modular, distributed, and scalable, accommodating hundreds of diagnostic inputs and actuator outputs. Each node is also connected to a memory network reflective memory providing a reliable, deterministic method of sharing memory between all nodes. Control algorithms are programmed as block diagrams in Matlab-Simulink providing a powerful environment for modelling and control design.
Pneumatic hydrogen pellet injection system for the ISX tokamak. We describe the design and operation of the solid hydrogen pellet injection system used in plasma refueling experiments on the ISX tokamak. The gun-type injector operates on the principle of gas dynamic acceleration of cold pellets confined laterally in a tube. The device is cooled by flowing liquid helium refrigerant, and pellets are formed in situ. Room temperature helium gas at moderate pressure is used as the propellant.
The tokamak plasma fuel content was observed to increase by 0.
Digital controlled pulsed electric system of the ETE tokamak. Primeiro relatorio. This reports presents a summary on the thermonuclear fusion and application for energy supply purposes. The tokamak device operation and the magnetic field production systems are described.
Full text: A fusion hybrid or a small fusion power output with low power tokamak reactor is presented as another useful application of nuclear fusion. Such tokamak can be used for fuel breeding, high-level waste transmutation, hydrogen production at high temperature, and testing of nuclear fusion technology components. In this work, an investigation of the plasma performance in a small fusion power output design is carried out using the BALDUR predictive integrated modeling code. The preliminary results using this core transport model show that the central ion and electron temperatures are rather pessimistic.
To improve the performance, the optimization approach are carried out by varying some parameters, such as plasma current and power auxiliary heating, which results in some improvement of plasma performance. Several of the basic design features are the following: an ignited plasma with a major radius of 4. The design, which utilizes the Westinghouse computer code for the COsting And Sizing of D-T burning Tokamaks COAST , mainly provides the sizes and geometries associated with the definition of the main component features for which a detailed engineering design can be effectively undertaken.
Design study alternatives, including a neutral beam driven design option, a design option with a toroidal field of 13 T at the coil, and a tungsten-shielded option are considered for the CCTR. Also included is the conceptual design of a Compact Fusion Engineering Device. Vacuum system of SST-1 Tokamak. The plasma will be confined inside the vacuum vessel while the cryostat houses the superconducting magnet systems TF and PF coils , LN 2 cooled thermal shields and hydraulics for these circuits. The vacuum vessel is an ultra-high UHV vacuum chamber while the cryostat is a high-vacuum HV chamber.
For this purpose, U-shaped baking channels are welded inside the vacuum vessel. During plasma operation, the pressure inside the vacuum vessel will be raised between 1. An ultimate pressure of 4. Similarly an ultimate vacuum of 2. Khan, Ziauddin, E-mail: ziauddin ipr. Baking of the. The traditional On-site collaboration Model that has to spend much money and time on international travel is not fit for the more frequent international collaboration.
This paper presents a design concept delineating a few key technical issues and addressing all significant details in the system architecture design. An advanced computational algorithm for systems analysis of tokamak power plants. Dragojlovic, Zoran; Rene Raffray, A. A new computational algorithm for tokamak power plant system analysis is being developed for the ARIES project.
The objective of this algorithm is to explore the most influential parameters in the physical, technological and economic trade space related to the developmental transition from experimental facilities to viable commercial power plants. This endeavor is being pursued as a new approach to tokamak systems studies, which examines an expansive, multi-dimensional trade space as opposed to traditional sensitivity analyses about a baseline design point.
The new ARIES systems code consists of adaptable modules which are built from a custom-made software toolbox using object-oriented programming. The physics module captures the current tokamak physics knowledge database including modeling of the most-current proposed burning plasma experiment design FIRE. The engineering model accurately reflects the intent and design detail of the power core elements including accurate and adjustable 3D tokamak geometry and complete modeling of all the power core and ancillary systems.
Existing physics and engineering models reflect both near-term as well as advanced technology solutions that have higher performance potential. To fully assess the impact of the range of physics and engineering implementations, the plant cost accounts have been revised to reflect a more functional cost structure, supported by an updated set of costing algorithms for the direct, indirect, and financial cost accounts. The present results demonstrate visualization techniques that provide an insight into trade space assessment of attractive steady-state tokamaks for commercial use.
The multi-institutional ARIES study has completed a series of cost-of-electricity optimized conceptual designs of commercial tokamak fusion reactors that vary the assumed advances in technology and physics.
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A comparison of these designs indicates the cost benefit of various design options. A parametric systems analysis suggests a possible means to obtain a marginally competitive fusion reactor. A synchronization system to digitalize TJ-1 Tokamak data. At TJ-1 Tokamak signals are stored on a channel magnetic memory.
In this report, a system to address those channels and synchronize readout is presented. A flexible software architecture for tokamak discharge control systems. The software structure of the plasma control system in use on the DIII-D tokamak experiment is described. This system implements control functions through software executing in real time on one or more digital computers. The software is organized into a hierarchy that allows new control functions needed to support the DIII-D experimental program to be added easily without affecting previously implemented functions.
This also allows the software to be portable in order to create control systems for other applications. The tokamak operator uses an X-windows based interface to specify the time evolution of a tokamak discharge. The interface provides a high level view for the operator that reduces the need for detailed knowledge of the control system operation. There is provision for an asynchronous change to an alternate discharge time evolution in response to an event that is detected in real time.
Quality control is enhanced through off-line testing that can make use of software-based tokamak simulators. The Alborz tokamak is a D-shape cross section tokamak that is under construction in Amirkabir University of Technology. One of the most important parts of tokamak design is the design of the poloidal field system. This part includes the numbers, individual position, currents and number of coil turns of the magnetic field coils. Circular cross section tokamaks have Vertical Field system but since the elongation and triangularity of plasma cross section shaping are important in improving the plasma performance and stability, the poloidal field coils are designed to have a shaped plasma configuration.
In this paper the design of vertical field system and the magnetohydrodynamic equilibrium of axisymmetric plasma, as given by the Grad-Shafranov equation will be discussed. The poloidal field coils system consists of 12 circular coils located symmetrically about the equator plane, six inner PF coils and six outer PF coils. Six outer poloidal field coils PF are located outside of the toroidal field coils TF , and six inner poloidal field coils are wound on the inner legs and are located outside of a vacuum vessel.
Advanced video coding systems. Specifically, the book introduces the tools of the AVS2 standard, describing how AVS2 can help to achieve a significant improvement in coding efficiency for future video networks and applications by incorporating smarter coding tools such as scene video coding. Topics and features: introduces the basic concepts in video coding , and presents a short history of video coding technology and standards; reviews the coding framework, main coding tools, and syntax structure of AV.
Large Aspect Ratio Tokamak Study. Reid, R. The plasma physics, engineering, and economic implications of high aspect ratio tokamaks were assessed in the context of extended burn operation. Using a one-dimensional transport code plasma startup and burn parameters were addressed. The pulsed electrical power requirements for the poloidal field system , which have a major impact on reactor economics, were minimized by optimizing the startup and shutdown portions of the tokamak cycle. A representative large aspect ratio tokamak with an aspect ratio of 8 was found to achieve a burn time of 3.
Calculation code of magnetic field generated by ferritic plates in the tokamak devices. However iterative calculations concerning the non-linearity in B-H curve of ferritic steel disturbs high-speed calculation required as the design tool. In the strong toroidal magnetic field that is characteristic in the tokamak fusion devices, fully magnetic saturation of ferritic steel occurs.
Hence a distribution of magnetic charges as magnetic field source is determined straightforward and any iteration calculation are unnecessary. Additionally objective ferritic steel geometry is limited to the thin plate and ferritic plates are installed along the toroidal magnetic field. Taking these special conditions into account, high-speed calculation code ''FEMAG'' has been developed. The presented examples are numerical results of design studies for JT modification.
Much progress in instrumentation and control has been made since then and the construction phase will be finished in August The TMS also measures the strains and displacements on the structures in order to monitor the mechanical safety. There are around temperature sensors, more than strain gauges, 10 displacement gauges and 10 Hall sensors. The TMS utilizes Cernox sensors for low temperature measurement and each sensor has its own characteristic curve. In addition, the TMS needs to perform complex arithmetic operations to convert the measurements into temperatures for each Cernox sensor for this large number of monitoring channels.
A special software development effort was required to reduce the temperature conversion time and multi-threading to achieve the higher performance needed to handle the large number of channels. We will describe the details of the implementations in this paper.
Design and construction of Alborz tokamak vacuum vessel system. At the heart of the tokamak is the vacuum vessel and limiter which collectively are referred to as the vacuum vessel system. As one of the key components for the device, the vacuum vessel can provide ultra-high vacuum and clean environment for the plasma operation. The VV systems need upper and lower vertical ports, horizontal ports and oblique ports for diagnostics, vacuum pumping, gas puffing, and maintenance accesses.
A limiter is a solid surface which defines the edge of the plasma and designed to protect the wall from the plasma, localizes the plasma—surface interaction and localizes the particle recycling. Basic structure analyses were confirmed by FEM model for dead weight, vacuum pressure and plasma disruptions loads.
Stresses at general part of the VV body are lower than the structure material allowable stress MPa and this analysis show that the maximum stresses occur near the gravity support, and is about 98 MPa. The magnet system of the Tokamak T upgrade. Khvostenko, P. The magnet system of the Tokamak T upgrade will obtain and confine the hot plasma in the divertor configuration. Plasma parameters are a major radius of 1. The magnet system includes the toroidal winding and the poloidal magnet system.
The poloidal magnet system generates the divertor with single null and double null magnetic configurations. The power supply system provides the necessary current scenarios in the windings of the magnet system. All elements of the magnet system will be manufactured by the end of The Tokamak T upgrade should begin operations in Petersburg Russian Federation ; Chudnovsky, A.
Petersburg Russian Federation ; Khayrutdinov, R. Petersburg Russian Federation ; Lukash, V. Petersburg Russian Federation ; and others. We have developed a code which evaluates the complex input impedance, the loading, and the spectral distribution of the launched power, of metallic antennas for ion cyclotron heating of large tokamak plasmas.
The current distribution along the conductors is obtained selfconsistently from a variational method. The plasma response is evaluated assuming that the WKB approximation can be used already at the plasma edge, thereby avoiding the lengthy integration of the wave equations in the plasma. This makes possible systematic scans over frequency or other parameters, while retaining a sufficiently large number of Fourier components in the radiated fields to ensure convergence of both the resistive and reactive part of the power. Optionally, the code can evaluate the antenna response in vacuum or with a dummy load, for comparison with test bank measurements.
We have applied the code to a few antennas of practical interest. The code reproduces accurately the expected transmission-line-like behaviour of a simple feeder-to-short antenna, and reasonably well the measured properties of the folded antenna of the ASDEX Upgrade ICRF experiment. This antenna is found to have particularly favourable properties, since its outer conductors present to the plasma a relatively uniform current over a broad range of frequencies, which, moreover, is always larger than in the return conductors.
The loading of the ''violin antenna'' recently proposed for use in ITER is found to be satisfactory in the vicinity of antenna resonance, although rather poor at other frequencies. Warmer, F. Warmer ipp. In order to study and design next-step fusion devices such as DEMO, comprehensive systems codes are commonly employed. The subsequently developed models include: a geometry model based on Fourier coefficients which can represent the complex 3-D plasma shape, a basic island divertor model which assumes diffusive cross-field transport and high radiation at the X-point, and a coil model which combines scaling aspects based on the HELIAS 5-B reactor design in combination with analytic inductance and field calculations.
In addition, stellarator-specific plasma transport is discussed. A strategy is proposed which employs a predictive confinement time scaling derived from 1-D neoclassical and 3-D turbulence simulations. This paper reports on the progress of the development of the stellarator-specific models while an implementation and verification study within an existing systems code will be presented in a separate work.
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This approach is investigated to ultimately allow one to conduct stellarator system studies, develop design points of HELIAS burning plasma devices, and to facilitate a direct comparison between tokamak and stellarator DEMO and power plant designs. Overview of tritium systems for the Compact Ignition Tokamak.
The Compact Ignition Tokamak CIT is being designed at several laboratories to produce and study fully ignited plasma discharges.
The tritium systems which will be needed for CIT include fueling systems and radiation monitoring and safety systems. Major new tritium systems for CIT include a pellet injector, an air detritiation system and a glovebox atmosphere detritiation system. The pellet injector is being developed at Oak Ridge National Laboratory.
Long pulse neutral beam system for the Tokamak Physics Experiment. Grisham, L. The neutral beam component of the heating and current drive systems will be provided by a TFTR beamline modified to allow operation for pulse lengths of s. This paper presents a brief overview of the conceptual design which has been carried out to determine the changes to the beamline and power supply components that will be required to extend the pulse length from its present limitation of 1s at full power.
The modified system , like the present one, will be capable of injecting about 8MW of power as neutral deuterium. The initial operation will be with a single beamline oriented co-directional to the plasma current, but the TPX system design is capable of accommodating an additional co-directional beamline and a counter-directional beamline. Hron, Martin; Sova, J. Aix — en — Provence, The purpose of this work is to assemble a code package for LWR core physics including coupled neutronics, burnup and thermal hydraulics. Multi-channel bolometer system on JFT-2M tokamak.
Multi-channel bolometer system is designed and installed to observe the radiation profile on JFT-2M tokamak. At the very top, large busbars transfer power from the power supplies to the current lead terminals. Two current leads for poloidal field coil 4 are mounted for insertion into the cooling test chamber. At bottom a "U-bend" link a piece of superconductor connects the two.
This assembly will be lowered into a cylinder under vacuum for cold tests under current. Portfolio Inside the cold factory Pipes and tanks of all sizes and colours, valves, compressors, truck-size electrical motors, zeppelin-like gas bags, puzzling contraptions evocative of sea mons [ Heat removal Moving 10 tonnes of water per second If ITER were a fusion power plant, the amount of heat produced by the machine would be partly absorbed by the steam generators and turbines that initiate the el [ Because they reduce the input power requirement for plant operation, high-temperature superconducting HTS current leads are one of the enabling technologies together with superconducting magnets for large-scale fusion power plants.
First driven by the high-energy physics accelerator community, the development of high-current HTS leads is now being pushed by magnetic confinement fusion towards larger currents. Series manufacturing is now underway and this pair—destined for the magnet feeder for poloidal field coil 4—will be the first to reach ITER.
The components are seen mounted in a ''cold termination box,'' which isolates the cryogenic components of the feeders from the environment.