As the next step for the fusion energy in China beyond ITER, the China Fusion Engineering Text Reactor (CFETR) aims to operate with duty time as 0.3~0.5, means that CFETR should operate at steady-state scenario. This provides a great challenge for the physical design of the heating the current driving system. In general, four different kinds of method as NBI, ECH, LHW and ICRH have been...
In order to satisfy the EAST first wall and divertor upgrade plan, a hypervapotron (HV) cooling concept is chosen to be developed as a candidate for the design of PFCs. The HV structure relies on internal grooves or fins and boiling heat transfer to maximize the heat transfer capability. The fabrication technology of W/Cu divertor has been developed at ASIPP (Institute of Plasma Physics...
In ITER poloidal field (PF) prototype converter testing, the Rogowski current transducer is used to measure the current in a DC bus bar. When thyristors, which are parts of PF converter, are triggered on, they will produce electromagnetic noise around. The noise signal, which has a strong amplitude and fixed frequency, is easy to be coupled by cable between Rogowski coil and integrator, and...
As the fusion experiment goes to steady state and more sophisticated diagnoses are developed, the experiment data becomes larger and collaboration between researchers tends to be more frequent. So a well-designed flexible and easy to use web visualization framework is becoming more important.
The new web visualization framework is designed and implemented based on ASP.NET MVC framework. It is...
The required peak current of ITER in-vessel vertical stability (VS) coil power supply is up to 80 kA, so VS coil power supply needs a PWM rectifier to achieve high power factor operation under the highly transient power demand. A new maximum current control method for three-phase PWM rectifier based on its mathematical model in d-q coordinate has been discussed. The control method samples...
Implementing weight window (WW) is a usual method for variance reduction (VR) of Monte Carlo simulation, however as for a complex and large model simulation it frequently encounter the long histories (LH in abbreviation) problem in parallel computing. LH behavior shows as the running time of a single particle history is significantly longer than that of normal histories. It would take a...
To provide high-efficient and low-cost way to meet international collaboration requirements for the EAST, a web-based remote participation system (RPS), details of which were first reported in the 10th IAEA Meeting in 2015, has been developed. The RPS team focused on the extension, update and optimization for the RPS during last two years. The purpose of this paper is to provide an update of...
With the development of magnetic confinement fusion, the new requirements and challenges are emerged for ITER NBI[1]. Briefly, It is required that the ion source of the neutral beam injection system should produce a uniform large volume high density plasma with the capability of long pulse steady state and long service life. Based on the EAST-NBI bucket ion source[2] where the main structure...
The Chinese Fusion Engineering Test Reactor (CFETR) is the next device in the roadmap for the realization of fusion energy in China, which aims to bridge the gaps between the fusion experiment ITER and the demonstration reactor (DEMO) [1]. CFETR will be operated in two phases: Steady-state operation and self-sufficiency with a modest fusion power of up to 200MW in Phase I, and DEMO validation...
This paper deals with an integration method of hybrid power filter in Tokamak Power System. The integration method not only takes full advantage of SVC which originally installed in Tokamak but also gives a combination of an active power filter to suppress the selective harmonics. Due to the rich harmonic spectrum in the AC side of non-linear load in Tokamak Power Systems, along with most...
Ultimately, a DEMO fusion power plant must mature the physics, design, and engineering/technology basis for a future fusion power plant (FPP). In doing so, it must also enable an extrapolable assessment of the economic performance of an FPP. Following discussions with stakeholders and fusion reactor experts, these goals have been further refined into a set of high-level plant requirements. In...
The neutral beam injector (NBI) is one of the plasma heating methods on fusion device, which has highest plasma heating efficiency and the clearest heat physical mechanism. The high power ion source is one of the key parts of NBI system. Compare to the traditional hot cathode ion source, the radio frequency (RF) ion source have many merits, such as higher lifetime because of no filaments,...
EAST research program aims at achieving steady-state long-pulse operations, which have been obtained with fully non-inductively current drive and heating, maintaining around zero loop voltage for nearly the entire plasma current flat-top in about 60s at EAST shot #67341 recently. Based on the analysis of non-inductive current fractions, high βp is desirable in order to sustain steady-state...
ITER magnet system consists of 18 Toroidal Field (TF) coils，a Central Solenoid (CS)，6 Poloidal Field (PF) coils 9 pairs of Correction Coils (CCs). These four types of the coils are relied on Cable-In-Conduit Conductors (CICCs). The CICC for the PF Coils of ITER is referred to as PF conductors. This paper is mainly presented the Phase array ultrasonic test (PAUT) results on PF conductor jackets...
The articulated arm robot has precise mechanical link, similar to the human arm and it is integrated with the ultrasonic testing system, which can provide users with a flexible automatic ultrasonic testing scheme. The Institute of Plasma Physics, Chinese Academy of Sciences, has introduced a multi joint mechanical arm ultrasonic testing system from the French M2M company, and developed a...
Lithium wall conditioning has been a routine method to reduce fuel recycling and impurity deposition, which significantly improves the plasma performance in EAST tokamak [1]. In the 2016 EAST experimental campaign, with the help of intensive lithium wall conditioning, one-minute steady state long-pulse H-mode discharge was obtained. However, the time and amount of lithium used for the daily...
Full penetration welding and 100% volumetric examination are required for all welds of pressure retaining parts of the CFETR(China Fusion Engineering Test Reactor) Vacuum Vessel (VV) according to the design manual. But not every welding joint can be tested with RT due to the structure and welding position. Therefore the ultrasonic testing (UT) has been selected as an alternative...
The ability of magnetic confinement to plasma can be improved by elongating plasma cross-section in EAST (Experimental Advanced Superconducting Tokamak). But elongated plasma has vertical displacement instability, without control, plasma will dash against wall of vacuum vessel and disrupt, that will cause failure of plasma discharge. So feedback control system is needed to restrain plasma...
It is limited for thermal conductivity detectors(TCDs) to measure hydrogen isotopes with gas chromatography in a large amount of helium gas environment. Then a new detection technology of ZD REDOX combined with chromatographic column was investigated in order to measure the low concentration of hydrogen isotopes in the atmosphere of tritium extraction system. The estimated detection limit for...
The Plasma Gun PG-QRO-1 is a Coaxial electrode plasma discharge device with Mather type geometry. This geometry has been used in the past to develop Plasma Foci, which produce a large spectrum in energy, with energies ranging up to tens of keV. The study of the interaction of magnetized plasmas with candidate materials for fusion reactors, is a main topic in fusion research. The PG-QRO-1...
A hybrid kinematic manipulator (HKM) is being designed at RACE (Remote Applications in Challenging Environments) to handle the large breeder blanket segments for DEMO. The payload of this HKM is around 80 tonnes, and its trajectory requires stringent position accuracy as it passes key points, in order to manoeuvre the blanket into and out of position in the vacuum vessel. The TARM (Telescopic...
In ITER and future fusion devices, a high radiation level for power exhaust will be mandatory to avoid thermal overload of divertor targets. Increasing divertor radiation by injecting impurities is a general and effective method to reduce scrape-off layer heat flux and to cool the divertor plasma to detachment. Impurities such as nitrogen (N2), neon (Ne) and argon (Ar) have been widely used in...
Primary concept design of CFETR (Chinese Fusion Engineering Test Reactor) has finished. In the fusion reactor, tritium is bred by mixed pebble bed in CFETR’s WCSB (Water Cooled Solid Blanket). In this study, the discrete element method (DEM) was used to study the mechanical behaviors and elastic moduli of mixed pebble beds. The effect of cyclic pressure p within the granular system in...
ITER machine will install a set of 45 diagnostics to ensure controlled plasma operation. Many of them are positioned in the upper & equatorial ports. US ITER diagnostics scope includes the design and integration of 2 equatorial port plugs (E03/09) and 2 upper ports (U11/U14). Each port contains three different zones starting from the in-vessel: the port plug zone, the interspace zone and the...
In CANDU fission reactors and also in fusion reactors, tritium should be recovered from large amounts of effluents for environmental and staff protection, for safety and for various applications.
The combined cryogenic distillation(CD) with catalyzed isotopic exchange between deuterium and liquid tritiated water(LPCE) it’s one of the most suitable technology for removal and its recovery. ...
Neutral beam injection in tokamaks results in a population of energetic particles (EP) that can drive instabilities in the Alfvén frequency range. In turn, instabilities can lead to redistribution or loss of EPs, thus affecting the controllability and predictability of quantities such as neutral beam (NB) current drive efficiency and radial profile of the non-inductive current fraction. In...
The Central Solenoid Model Coil (CSMC) of China Fusion Energy Test Reactor (CFETR) is currently in the design and manufacture process. CSMC assembly consists of the winding pack, an outer NbTi coil，a middle Nb3Sn coil, an inner Nb3Sn coil and a pre-load structure. The highest field of the model coil is 12T, while the highest change rate of magnetic field of the conductor is 1.5T/s. Due to the...
The breeder blanket and divertor are crucial plasma facing components (PFC) in a fusion reactor. The helium cooled blanket and divertor concepts have exhibited the best potential to come up to the highest safety requirements and therefore been chosen for the development object. As a result of high heat flux radiated from the plasma in the fusion reactor and high power density nuclear heat...
ITER is the world’s largest fusion device currently under construction in the South of France with over 50 diagnostic systems to be installed inside the port plugs (PPs), the interspace or the port cell region of various diagnostic ports. The Diagnostic First Wall (DFW) and Diagnostic Shielding Modules (DSM) are designed to protect front-end diagnostics from plasma neutron and radiation while...
HL-2M is a medium-sized copper-conductor tokamak under construction at the Southwestern Institute of Physics (SWIP). The designed plasma parameters are as follows, plasma current=3 MA, toroidal field = 3 T, major radius =1.78 m, minor radius = 0.65 m, flux-swing > 14 Vs, plasma pulse ~ 5 s, with a plasma shape of elongation = 2 and triagularity > 0.5. The demountable toroidal field coils...
In HL-2M the magnetic field power supply includes CS power supply and sixteen poloidal field power supplies. Each power supply is consists of three-phase full bridge thyristor converters and phase control is used to fire thyristor. The AC power of magnetic field power supply is provided by a six-phase motor generator with two Y windings of shifting 30°. The AC voltage waveform is distorted due...
Divertor solutions to efficiently disperse heat from fusion reactors are critical because the maximum steady-state power load is limited to qt ≤ 5-10 MW/m2 to the divertor target. This may pose a special challenge for next-step Advanced Tokamaks (AT), which will have lower plasma density than ITER for high performance long pulse or high duty cycle operations. A new Small Angle Slot...
Wendelstein 7-X (W7X) is a large, superconducting stellarator with modular coils and an optimized magnetic field.
A multi-purpose manipulator (MPM) system has been developed and installed on the W7-X vessel, aimed at investigating the edge plasmas of the stellarator. It is a flexible tool for integration of a variety of different diagnostics as e. g. electrical probes, probing magnetic coils,...
Large machines for fusion research and the fusion rectors have hostile environmental conditions characterised by high level of radiation, vacuum and temperature both in the vessel and in the port cell and the close area, commercial displacement sensors like linear and rotary encoders and their electronics are not suitable with this conditions. This problem has been approached and solved...
Tearing Mode (TM) creates magnetic islands in the tokamak. Using external resonant magnetic perturbation (RMP) coils is a convenient method to affect magnetic islands. To avoid mode locking and major disruption, the stabilization of TM control by using RMP is a promising method. A new method for applying modulated magnetic perturbation is presented to suppress magnetic island and accelerate...
The development of radio frequency (RF) negative ion sources for neutral beam systems requires knowledge of the plasma parameters. Optical emission spectroscopy (OES) is a non-invasive and in situ diagnostic tool, so optical emission spectroscopy diagnostic system are designed to be applied to the measurements of the RF negative ion source, and diagnostic principle and simplified analysis...
For supplying enough power for 2M-HL Tokamak, a new 300MVA pulse generator has been developed, the new generator with 400 tons of rotor to stored energy will be driven by an 8500kW asynchronous motor . In order to reduce the large starting current, a high voltage variable frequency converter has been developed as the starting device because of the large inertia. Liquid resistors in series with...
Artificial neural-networks (NN) have been used to model the potential-energy surfaces of, for example, bulk silicon or copper surfaces. NNs may reach the structural and energetic quality of density-functional theory (DFT) at a small computational cost [1][2]. The authors intend to develop NN potentials based on ab initio data as an alternative approach to empirical potentials for the atomistic...
The ITER Tokamak, designed to study deuterium-tritium fusion reactions and to demonstrate its viability as a sustainable and clean energy source, is currently being built in South France, on the Cadarache site. Its vacuum system, one of the largest and most complex vacuum systems ever to be built, requires several hundred vacuum sensors for pressure monitoring of its high vacuum systems.
High...
The JET neutral beam injection system incorporates a calorimeter in each beamline, comprising 2 large cooled copper panels (about 2.5m x 1m) instrumented with thermocouples to provide diagnosis of the beam shape and alignment. The panels are rotated out of the beam path to allow the beam to enter the torus; they are inertially cooled and can only sustain full beam power for a fraction of a...
Abstract – The PF1A coil is one of the Poloidal Field (PF) shaping coils on the NSTX-U machine. It is critical for shaping highly elongated, and high triangularity plasmas current. In July 2016, the failure of the PF1A Upper coil resulted in shutdown of the NSTX-U experiment. As part of the causal analysis, it was discovered that several passive structures around the PF1A coil had an adverse...
Glow discharge cleaning (GDC) shall be used on ITER device to reduce and control impurity and hydrogenic fuel out-gassing from in-vessel plasma facing components. After first plasma, permanent electrodes (PEs) will be used to replace Temporary Electrodes (TEs) for subsequent operation. These PEs will be used inside vacuum vessel and during plasma operation, major disruption and vertical...
E. Veshchev1*, Ya. Sadovskiy2, L. Begrambekov2, O. Bidlevitch2, O. Gordeev2, P. Shigin1, G. Vayakis1, M. Walsh1, R. Walton1
1 ITER Organization, CS 90 046, 13067 St Paul Lez Durance Cedex, France
2 National Research Nuclear University (MEPhI) - NRNU MEPhI
ITER is a basic nuclear installation and as such, safety is one of the most important drivers in the design. The ITER Licensing...
Investigation on effects of wettability on liquid metal free surface film flow states have been performed by numerical simulations and experiments to establish a film flow which can cover the whole bottom solid surface. The effects of density of fluid, inlet film thickness and the width of bottom solid surface on the film flow states under poor wettability conditions have been investigated by...
Abstract:
In Neutral Beam Injector (NBI), ions are accelerated to desired energy (from ~10 kV to ~MV range) by an electrostatic multi-aperture grid system of an ion source. Accelerated ions subsequently neutralized in a gas cell called neutralizer. To maintain the electrostatic lens configuration, grid plates are placed closely packed (~mm distance) parallel to each other. Paschen-breakdown...
The Chinese Fusion Engineering Test Reactor (CFETR) is designed as the next fusion device in China aiming to bridge the gaps between the fusion experimental reactor ITER and the demonstration reactor (DEMO). The current EAST tokamak will provide a long-pulse, high power test bench for advanced operation scenarios under actively cooled metal wall condition for CFETR [1]. To achieve long-pulse...
The quench protection switch (QPS) is an indispensable component to ensure the safety of the magnet coils of a superconductive tokomak when a quench happens. The two most important functions of a QPS are to carry high direct current during normal operation and to interrupt the high direct current when a quench occurs. In this paper, the second commutating process of a QPS based on artificial...
The liquid lithium has been considered as a suitable selection for the plasma facing component (PFC) materials in fusion reactors because of its plenty of advantages for removing the heat fluxes, incident tritium and impurity effluxes, and enabling a lithium wall fusion regime. However, under a complex magnetic field, the flowing liquid metal will exhibit complicated flow characteristics...
Using liquid lithium film as the plasma facing component (PFC) is the prospective scheme in the future magnetic confinement fusion to withstand the plenty heat flux and improve the plasma performance. Under the magnetic field along the film spanwise direction, the lithium film flow will exhibit a complicated flow characteristics induced by the action of extra Lorentz force, which named...
Abstract
In order to verify the integrity of the insulation of superconducting magnet, it is needed to perform the Paschen test on the insulation after its manufacture. The vacuum vessel for the Paschen test is required to keep for an adequately long time under the pressure values of different degrees. To achieve the low pressure of the vacuum vessel, isolating the pumping unit from the...
The fast plasma boundary reconstruction is usually used for real-time control of tokamak plasma. In EAST experiment, the time consuming for boundary reconstruction should be within 1ms to meet the need of real-time control. A fast algorithm based on visible imaging diagnostics is developed in EAST to reconstruct the plasma boundary directly and independently. Compared to the results of EFIT,...
Thermal Shield (TS) is to be installed between vacuum vessel/cryostat and superconducting magnet in ITER tokamak. The TS plays a role in minimizing thermal radiation load onto the magnet. The TS has to be cooled by flowing 80 K helium gas inside cooling pipes welded on the TS surface. The helium coolant is supplied from the cryoplant via manifold pipes and distributed to all TS segments. Flow...
It is necessary to take effective cooling methods and remove the high heat flux from the divertor which sustains one-sided high heat fluxes over 10 MW/m2 in steady state. In order to ensure the reliability and security of the divertor in the fusion reactor, it is necessary to conduct the heat transfer and structural assessment of cooling tube in the divertor. In this paper, the heat transfer...
Inertia load analysis of ITER equatorial and upper port plug EPP9 and UPP14
Han Zhang1, Yuhu Zhai1, Julio Guirao2, Silvia Iglesias3, Peter Titus1
1Prineton Plasma Physics Lab,Princeton, New Jersey, hzhang@pppl.gov
2ITER Organization, Route de Vinon sur Verdon, 13067 Saint-Paul-lez-Durance, France
3AETEC, Advanced Engineering Technologies S.L. 33206 Gijon, Spain
The work presented in this...
The Neutral Beam (NB) system for ITER is composed of two heating neutral beam injectors (HNBs) and a diagnostic neutral beam injector (DNB). A third HNB can be installed as a future up-grade. This paper will present the design solution of the sealed interface between the components so called ‘Neutral Beam Front End Components’. The components to be considered are the Drift Duct, the Vacuum...
The tritium production is a key issue in the fuel recycle for DEMO blanket. It is affected by the temperature field inside the blanket interior due to the temperature requirement of the tritium release and the recovery. This paper discusses the tritium breeding ratio issues based on a PWR water-cooled blanket module. In particular, the variation trend of TBR is explored with the change of...
The design and the operations of a tokamak often require to assess the feasibility of a desired experimental scenario with the available power supplies (PSs). After the definition of the evolution of the current waveforms in the supplied conductors (active elements, AEs) and in the plasma, it is necessary to verify if the PS equipment is able to produce them, also taking into account the...
For the quench detection of the superconducting busbars and joints in the ITER Feeder system, several high voltage (HV) instrumentation wires should be led out from the electrical insulation layers to transmit the voltage potential signal to the data acquisition systems. The penetration of the HV instrumentation wires through the intact insulation layers introduces a potential defect in the...
In order to improve the experimental parameters on the HL-2A device and meet the requirements of the HL-2A modification, the capability and pulse duration of the auxiliary heating system should be improved greatly. The high voltage power supply (HVPS) which is based on PSM technology is a method of controlling the total output voltage of many identical DC choppers connected in series by means...
As one of key technical specification, the anti-fatigue performance of plasma-facing components (PFC) in fusion reactor receives widely concerns. Many researchs concluded that the micro structure on PFC metal connecting interface greatly affects its fatigue performance of interface, especially for some micro/nano scale pories in connection zone, which are difficult to be detected by ordinanry...
The flywheel six-phase generator operated in pulse mode supply power of the magnetic field on HL-2M tokamak. The precise and stable control of six-phase generator is essential for obtaining high beta, steady state plasmas in HL-2M.
Concretely for the power supply of the toroidal field coils on HL-2A, it consists of six-phase synchronous generators with their excitation systems, diode...
China Fusion Engineering Test Reactor (CFETR), as a new tokamak device to bridge the gap between ITER and DEMO, is developed for further research fusion power plant by China National Integration design Group for Magnetic Confinement Fusion. As a key component to maintain the reliability in run of high-temperature plasma in tokamak, vacuum vessel (VV) has a direct influence on the operation...
The dual coolant lead-lithium (DCLL) blanket concept, which is utilized in the Fusion Nuclear Science Facility (FNSF) conceptual design, is based on a helium-cooled first wall and blanket structure with RAFS (Reduced Activation Ferritic Steel) and a self-cooled LiPb breeding zone. The objective of this work is to develop a multiphysics modeling process in order to optimize the design and...
NBImag is a code suitable for the design and optimization of complex magnetic field configurations, such as that of a multi-aperture, multi-stage negative ion source and accelerator. The NBImag code has been developed for the design of the ITER Neutral Beam Injector (NBI), whose full-size prototype, MITICA, is presently under construction in Padova, Italy. The ITER injector shall produce a...
The He-cooled Lithium Lead breeder blanket could be developed with the utilization of relatively mature material technology, which is used by Reduced Activation Ferritic / Martensitic (RAFM) steel as the structural material in China. It is necessary to analyse the first wall structure heated because of the thermal stress from two coolants in the blanket which would directly affect the blanket...
A flush-mounted Langmuir probe system has been built on the lower graphitic divertor targets on the EAST tokamak in 2016, which is transformed from the previous divertor Langmuir probes, aimed to reduce the erosion from high energy particle and strong heat flux on the probe surfaces exposed in the plasma, and explore new structure application. During the 2016 EAST campaign, the flush-mounted...
The beryllium pebble bed and Li2TiO3/Be12Ti mixed pebble bed are selected to realize neutron multiplication and tritium breeding in the Water-cooled ceramic breeder blanket (WCCB) of China Fusion Engineering Test Reactor (CFETR). In order to evaluate and improve the performance of WCCB, studies of the thermo-mechanics of the concerned pebble beds are necessary.
In the current research, a...
Performance analysis on the VUV imaging system in EAST tokamak
Z.J.Wang1, 2, T.F.Ming1, X.Gao1, 2, Y.M.Wang1, F.Zhou1, 2, F.F.Long1, 2 and EAST Team
1Institute of Plasma Physics, Chinese Academic Sciences, Hefei, China
2Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, China
*tfming@ipp.ac.cn
In the present fusion research, magnetically confined...
Abstract-Experimental Advanced Superconducting Tokamak(EAST) device is a D-shaped full superconducting tokamak with actively water cooled plasma facing components. Before this upgrade, three generations of divertors, which, respectively, are steel divertor and carbon divertor and International Thermonuclear Experimental Reactor (ITER)-like divertor have designed. To achieve long pulse and high...
The 6 MW/4.6 GHz lower hybrid current drive (LHCD) system as an effective approach for auxiliary heating and noninductive current drive has been designed and installed with twenty-four 250 KW/4.6 GHz high power klystron amplifiers in the experimental advanced superconducting tokamak(EAST). The power control system of 4.6GHz lower hybrid wave (LPCS) in continuous wave mode has been set up,...
The Water Cooled Ceramic Breeder blanket(WCCB), which employs the operating conditions of Pressurized Water Reactor(PWR), namely inlet/outlet temperature of 285/325℃ and pressure of 15.5MPa, is being comprehensively researched in the Institute of Plasma and Physics Chinese Academic of Sciences. As an important component of the Water Cooled Ceramic Breeder blanket(WCCB), the first wall faces...
The GDC PE in UPP14 is one of the plasma facing components in the ITER tokamak device. It will get a large number of thermal loads such as radiation and charge-exchange, neutron heating. So it would need the active cooling requirements from Diagnostic Port Plugs(DPP).
The electrode model consists of three parts: the electrode head, the electrode rod and pipes.The first layer channel shape is...
HL-2M tokamak is considered as one of the most important short pulse device for future fusion research in China which is being built at Southwestern Institute of Physics. In the vacuum vessel of the HL-2M, The first wall in weak magnetic side is designed to protect the vacuum vessel, cryopump, RMP coils and diagnostic components from the plasma particles and heat loads. Currently, the...
The ITER Tokamak Cooling Water System (TCWS) is designed to provide cooling and baking for the Primary Heat Transfer Systems (PHTSs) and relevant systems including the first wall/blanket, vacuum vessel, divertor, etc. For its characters of promising to enhance the heat transfer performance and increase critical heat flux (CHF), HyperVapotron (HV) elements has been put forward as heat removal...
Sufficient pumping speed and good pumping performance should be guaranteed for the HL-2M Tokamak.Technical parameters were obtained by directly simulating with the Monte Carlo method for HL-2M in-vessel cryopump under molecular flow conditions. The predicted pumping speed of bare pump is 51.29 m3/s for H2, 38.04 m3/s for D2 and 24.94 m3/s for He. An advanced divertor system will be installed,...
The Poloidal Field (PF) coils are one of the main sub-systems of the ITER magnets. The PF6 coil is being manufactured by the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) as per the Poloidal Field coils cooperation agreement signed between ASIPP and Fusion for Energy (F4E).
The ITER PF6 winding pack is composed by stacking of 9 double pancakes. Each double pancake is...
Linear plasma devices can produce low energy, high flux plasmas to simulate boundary conditions in tokamaks. Recently, two new linear plasma facilities have been built at the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). To understand the hydrogen isotopes behavior in first wall materials, the PREFACE (Permeation and Retention Evaluation FACility for fusion Experiments)...
Pellet injection, which is regarded as the most promising technique for the research of edge plasma physics, can control the edge localized mode (ELM) [1] and reduce the power threshold of L-H transition [2]. Since the installation of the 10 Hz pellet injection system [3] in Experimental Advanced Superconducting Tokamak (EAST), lots of experiments have been carried out. The 10 Hz pellet...
An important tool for the progress of reflectometry is numerical simulation, able to assess the measuring capabilities of existing systems and to predict the performance of future ones in machines such as ITER and DEMO. A novel 2D full-wave FDTD code, REFMULF, presented here is able to cope with full polarization waves, coupling the Transverse-Electric Mode (TE, X-mode) with the...
W is a promising plasma facing material for fusion devices. It is expected to suffer from the transient heat flux during normal ELMs, abnormal VDEs and plasma disruption events. In the next fusion device such as the ITER, the transient high heat flux can reach up to several MJ/m2 in a very short pulse (~ms), which is as high as enough to cause the surface damages especially in form of cracks...
Microwave diagnostics including reflectometry and electron cyclotron emission are the candidates for tools to measure the basic parameters such as electron density and temperature profile on CFETR. They have high spatial and temporal resolution with the radial coverage of the entire plasma. Nevertheless, because of the transmission of signal relies on the waveguide which can survive in the...
A new method of real-time reactive power detection is proposed, which aims to be applied in reactive power for Tokamak coil power supply volatility, high random and the contradiction between accuracy and real-time of traditional method. It based on AC/DC system active power balance principle, and considering the electric network voltage sag, distortion and excitation current of transformer....
For successful future Fusion Power Plant operation, tritium self-sufficiency is an essential element of the multiple technical challenges facing the fusion programme. In particular all the different types of candidate blankets will have to make use of different functional materials, such as SiC for flow channel inserts (FCI), ceramic coatings on steel for liquid metal blankets, and Li-ceramic...
The Korean fusion demonstration reactor (K-DEMO) will be operated in a highly irradiated condition by 14 MeV neutrons from D-T plasma. During this condition, irradiated materials generate radioactive nuclides. The nuclides emit decay gammas during operation and even after the shutdown of the tokamak reactor. One of the important safety-related maintenance areas in the tokamak reactor is the...
First wall (FW) of the DEMO reactor should protect the breeding blanket and mechanical construction elements of the burning plasma exposure. The plasma impacts the wall surface by heating and by energetic particles. The heat load on FW during steady state burning mainly consists of the following factors: (i) the plasma photonic radiation, (ii) the plasma heat flux along the magnetic field...
Beryllium is planned to be used as the neutron multiplier in helium cooled pebble-bed (HCPB) breeding blanket concept for DEMO power plants. Under neutron irradiation a large amount of helium and tritium is produced in beryllium. The key issues of neutron irradiation of beryllium are helium-induced swelling and tritium retention and release. Because of safety requirements, the in-pile tritium...
The debate on which will be the operative mode of a future commercial fusion power plant, steady state or pulsed, is still open even in the on going pre-conceptual design phase of the European demonstration power plant, DEMO.
As part of a series of studies on the economics of alternative options of commercial fusion power plant carried out with the FRESCO (Fusion Reactors Simplified Cost)...
ITER is one of the most ambitious energy projects in the world today. The Neutron Flux Monitor (NFM) diagnostics module will be installed on ITER, it measures the total neutron emission, providing the evaluation of the fusion power, and will be positioned in the occluded Equatorial Port #07, more exactly mounted on the inner Bio-shield wall and within penetration from Tokamak Pit to the NB...
CFETR (China Fusion Engineering Test Reactor) CS (Central Solenoid) model coil made with CICC (Cable in Conduit Conductor) superconductor had been developed in Institute of Plasma Physics, Chinese Academy of Sciences. The highest field of CS model coil is 12T, and the largest magnetic field change rate is 1.5T/S. CS model coil mainly consists of two Nb3Sn inner coils and three outer NbTi...
The quench detection for EAST superconducting CS coils is considered the most difficult quench detection work because of pulsed operation and the strong coupling with pulsed coils and huge plasma current. The coupling coefficient between superconductor and plasma is not fixed unlike the coupling with pulsed coils because the plasma current configuration is constantly changing. It lead to false...
Fire is one of main scenario for accidental tritium release in tritium handling facilities. Preventing this tritium escape to the environment requires maintaining sub-atmospheric pressure in the affected rooms and detritiation of the gas prior to its discharge. In all gas detritiation systems designed to process a large gas flow (in JET, ITER) first operation stage is catalytic conversion of...
Edge plasma code package SOLPS5.0 is employed to study the effects of upstream density on divertor power width λq for EAST L-mode discharges. The divertor power width, which is an important physical and engineering parameter for diverted tokamak fusion devices, is determined by the parallel and perpendicular transport in the SOL region. Upstream density scan is implemented in the simulation to...
The upper divertor of EAST had been upgraded as ITER-like monoblock configuration after 2012 experimental campaign. Compared to previous graphite divertor, it can greatly improve handling capability which is capable of offering an opportunity to study ITER-related plasma physics and engineering and to study the performance of the advanced tungsten divertor at the same time. During plasma...
The test about simple CDA+MIK quench detection method implemented a total of about 100 charging runs on EAST in the past two years, aiming at verifying this new method whether apply it to ITER cs coils or not.This project is supported by the ITER Organization (IO).
To obtain this target, the whole instrumentation hardware have been developed and installed on EAST and used to generate...
This paper is focused on the analysis of socio-economic benefits of the ongoing R&D program on big science such as nuclear fusion in Korea. The spillover effects are understood here as positive externalities of publicly funded R&D activities that may be revealed at the companies’ level in the form of newly created knowledge stock; development of innovative products/ processes with broader...
Due to the fast response, high reliability and one-time-use property, explosive driven circuit-breaker known as pyrobreaker(PB) has been applied in several high power supply systems. This paper presents the designing process of a new two-section PB with the capability of opening a DC current of 70 kA under a voltage up to 20kV. In accordance with the CFETR (China Fusion Engineering Test...
Tungsten (W) is considered as the most attractive plasma facing material for future fusion devices attributed to its outstanding properties. During the operation of plasma, helium ions produced by deuterium and tritium fusion reaction will impinge on W, which will raise more complicated tritium retention behavior in W. In the present work, the deuterium retention behavior in helium irradiated...
The liquid PbLi and PbBi alloys have been selected as one of the most promising coolant materials in fusion blanket and accelerator driven subcritical (ADS) reactor, respectively. The velocity distribution in the flow channel of blanket will greatly affect the efficiency of heat transfer and materials corrosion, so it’s necessary to carry out relevant researches to obtain the detailed flow...
In the breeding blanket fusion reactor, the dynamic viscosity of liquid metal (LM) is influenced by heat transfer, leading to the change of velocity distribution. The effect of heat transfer on magnetohydrodynamic(MHD) flow in a rectangular duct at high Hartmann Number is investigated by a coupling method. In this method, the velocity field is calculated through a second-order projection...
Tritium breeder materials are significant for blanket design of fusion reactor. However, during blanket operation, the ceramic breeder materials will be subjected to neutron irradiation which could be detrimental to mechanical properties. Because of its good chemical stability and available tritium release behavior, Li2TiO3 is becoming one of candidate ceramic breeder materials.
In this...
Tokamak as the most promising way to achieve fusion energy, the reliability of its plasma control system (PCS) is of great importance. J-TEXT Real-Time Framework (JRTF) is the next generation real-time framework for tokamak plasma control of J-TEXT. Introducing object-oriented programming (OOP) technology, JRTF is an advanced framework and can be a future candidate for developing PCS real-time...
The International Thermonuclear Experimental Reactor (ITER) Poloidal Field (PF) power supply has 14 thyristor based ac/dc converter units to feed six PF coils.PF1 and PF6 coils are both fed by one four-quadrant converter unit respectively, while the PF2-PF5 coils are supplied power by three four-quadrant converter units connecting in series and under sequential control to reduce reactive power...
The Chinese Fusion Engineering Test Reactor (CFETR) is the next device scheduled in the roadmap to realize fusion energy in China[1]. It aims to bridge the gaps between ITER and DEMO. Steady-state operation is one of the key issues of CFETR. The EAST tokamak will provide a long-pulse, high power test bench for advanced scenarios under actively cooled metal wall condition, which will play an...
The Water Cooled Ceramic Breeder blanket (WCCB) is one of the blanket candidates for Chinese Fusion Engineering Test Reactor (CFETR). The conceptual of WCCB for CFETR under 200MW fusion power has been designed based on pressurized water cooled reactor (PWR) technology. RELAP5 code, which is mature and often used in transient thermal hydraulic analysis in PWR reactor, is selected as the...
The China Fusion Engineering Test Reactor (CFETR) is the next device in the roadmap for the realization of fusion energy in China, which aims to bridge the gaps between the fusion experimental reactor ITER and the demonstration reactor (DEMO). CFETR will be operated in two phases: Steady-state operation and self-sufficiency will be the two key issues for Phase I with a modest fusion power of...
3D metal printing technology was selected for the development of fusion divertor research, and the optimization of thermo-hydraulic performance with a water cooling in a Korean heat load test facility by using electron beam (KoHLT-EB). The various cooling design for ITER and DEMO divertor have been fabricated for the enhancement of cooling performance, such as swirl tube and hypervapotron. The...
Divertor is one of the most challenging and important components in DEMO plants, since the enormous heat load from plasma applied onto the divertor target must cool down. In a conceptual study of the Korean fusion demonstration reactor (K-DEMO), a water-cooled divertor concept applying the tungsten monoblock type was of primary consideration. The target peak heat flux of 10 MW/m2 was set in...
Since the 1950’s Next Step fusion devices and power plant studies have been developed for a number of magnetic confinement systems but an open question remains…can a magnetic fusion device be simplified to the point where it will be cost competitive and operate with high availability? Concept designs based on the advanced tokamak (AT), spherical tokamak (ST) and the quasi-axisymmetric...
In the 2016 EAST experimental campaign, a steady-state long-pulse H-mode discharge lasting longer than one minute has been obtained using only Radio Frequency heating and current drive. Integrated modeling of one long-pulse H-mode discharge has been performed with equilibrium code EFIT, and transport codes TGYRO and ONETWO under integrated modeling framework OMFIT. The plasma current is...
Hydrogen-water exchange reaction is one of the most useful methods to concentrate heavy hydrogen isotopes from an admixture containing hydrogen-rich gas and heavy water. Pt-based hydrophobic catalyst had attracted much research interest in the reaction between liquid water and hydrogen. The hydrophobic support prevented liquid water from covering the active sites of the Pt catalyst, hence the...
Reflectometry system on EAST provides density profile and fluctuation measurement. The profile reflectometry worked under Q, V and W band, and the fluctuation reflectometry operated at fixed points in V band with 8 poloidal correlation channels. In present, an upgrade of reflectometry is being carried out on EAST. The U and E band profile reflectometry will be added into the current system. A...
