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This paper gives a summary of the organization and the presentations delivered at the 10th Conference on Magnetically Confined Fusion Theory and Simulation (CMCFTS) held in Zhuhai, China, from 28th to 31st October 2022. The conference focused on the latest progress in the research of the magnetic confined fusion plasma theory and simulations, as well as the large-scale numerical simulation techniques developed in recent years. This conference is held both online and offline, with about 110 domestic participants from 18 institutes participating in the live conference, and the statistical data from the live broadcast platform indicated that the online conference attracted over 20 000 views per day. A summary of the conference is given, and the history of the CMCFTS is presented. A brief introduction to the poster section is also included in this paper.

In fusion research, the diagnostic data are obtained from different diagnostic systems, which are relatively independent (in terms of the response function, noise, calibration, etc…). The consequence is that many measurements providing the same physical quantity could provide different results. In this work, the Bayesian probability inference has been applied to the frequency modulated continuous wave reflectometry and the Far-infrared laser interferometer diagnostic systems on HL-2A tokamak, offering the integrated data analysis (IDA) for electron density profile reconstruction. With the implementation, it is demonstrated that more comprehensive inference could be delivered from IDA compared to the traditional individual data analysis technique. The data analysis program based on the Bayesian inference model has been developed to reconstruct the two-dimensional electron density profile, which permits to be further implementation of the HL-2A/2M IDA framework in the near future.

Transport of fast ions is a crucial issue during the operation of ITER. Redistribution of neutral beam injection (NBI) fast ions by the ideal internal magnetohydrodynamic (MHD) instabilities in ITER is studied utilizing the guiding-center code ORBIT (White R B and Chance M S 1984 Phys. Fluids 27 2455). Effects of the perturbation amplitude A of the internal kink, the perturbation frequency f of the fishbone instability, and the toroidal mode number n of the internal kink are investigated, respectively, in this work. The n = 1 internal kink mode can cause NBI fast ions transporting in real space from regions of 0 < s ≤ 0.32 to 0.32 < s ≤ 0.53 , where s labels the normalized plasma radial coordinate. The transport of fast ions is greater as the perturbation amplitude increases. The maximum relative change of the number of fast ions approaches 5% when the perturbation amplitude rises to 500 G. A strong transport is generated between the regions of 0 < s ≤ 0.05 and 0.05 < s ≤ 0.12 in the presence of the fishbone instability. Higher frequency results in greater transport, and the number of fast ions in 0 < s ≤ 0.05 is reduced by 30% at the fishbone frequency of 100 kHz. Perturbations with higher n will lead to the excursion of fast ion transport regions outward along the radial direction. The loss of fast ions, however, is not affected by the internal MHD perturbation. Strong transport from 0 < s ≤ 0.05 to 0.05 < s ≤ 0.12 does not influence the plasma heating power of ITER, since the NBI fast ions are still located in the plasma core. On the other hand, the influence of fast ion transport from 0 < s ≤ 0.32 to 0.32 < s ≤ 0.53 needs further study.

Direct-current ionization breakdown in argon at very high voltage on the low-pressure branch of the Paschen curve is studied by means of kinetic simulation. The employed particle-in-cell/Monte Carlo collision model tracks the motion of electrons, ions and fast neutral atoms, as well as their collisions with the background gas. Secondary electron emission due to the bombardment by ions and fast atoms, as well as backscattering of different species on the electrode surfaces are also consistently accounted for. To validate the model, we compare the Paschen curve predicted by kinetic simulations against published experimental results as well against the prediction of a reduced (fluid) model. The model is then applied to predict, for the first time, the low-pressure branch of the Paschen curve for argon gas in the 10–300 kiloVolt range of applied voltage. One of the findings is the existence of a turning point on the Paschen curve at V b r ≈ 20 k V and p d ≈ 0.08 T o r r ⋅ c m , where V b r is the breakdown voltage and the reduced pressure p d is the product of the gas pressure with the inter-electrode distance. According to our analysis, the presence of the turning point is due to the phenomena of electron and ion runaway in high electric field. We further investigate the role of the heavy species (i.e. ions and fast neutral atoms) in sustaining the Townsend discharge at high voltage and thus setting the breakdown threshold. Specifically, the role of fast atoms is significant over the entire low-pressure branch of the Paschen curve due to their contribution to both ionization and secondary electron emission. Also, the ions, as the precursor for the fast atoms, show an important influence on the latter process. The newly predicted low-pressure branch of the Paschen curve for argon at high voltage should provide an essential reference for the design of high-voltage devices, e.g. circuit breakers in electrical power transmission.

Tungsten (W) transport and screening in the edge plasma are investigated for EAST high dissipative divertor conditions. By combining the 1D impurity fluid model (1DImpFM) and the two-point model formatting (2PMF), W screening is proved to be enhanced for high upstream plasma density conditions, mainly because the impurity temperature gradient velocity decreases with the increase of the upstream plasma density. Based on dedicated EAST density ramp-up experiments, 2D simulations of W erosion and transport are carried out for different levels of dissipative divertor conditions by using the SOLPS-DIVIMP code package, and the modeling results are benchmarked with the 1DImpFM analytic model. The prompt-redeposition, the divertor screening, and the main SOL screening are quantitatively analyzed. For detached divertor conditions, the increase in the W ionization length reduces the prompt redeposition rate, but both the divertor screening and SOL screening are reinforced. The 1DImpFM can interpret well the W leakage in the near separatrix region; however, the 2D simulations suggest that the impurity pressure gradient force which is neglected by the 1DImpFM plays an important role, especially in the far-SOL region. With the divertor condition varied from the high-recycling regime to the deep detachment regime, the W source moves from the near strike point region to the far SOL, and thus makes the W transport in the far SOL more important. Therefore, the impurity pressure gradient force cannot be neglected for edge W transport analysis, especially for the detached divertor conditions.

Metal fibrous felt particulates filter has the advantages of high mechanical strength, long service life, large dust capacity, high filtration accuracy, low resistance loss and high temperature resistance. In order to obtain the influence of structural parameters of metal fibrous felt on the characteristics of steady-state filtration efficiency, the effects of structural parameters of filter material such as porosity, fiber felt thickness and fiber diameter on steady-state capture efficiency under different filtration speeds are theoretically calculated and analyzed by using numerical calculation method. The results show that the structural parameters have an important impact on the steady-state filtration efficiency, which must be controlled within a reasonable range. Reducing the surface filtration speed to less than 0.1m/s can effectively improve the filtration efficiency. This paper provides a theoretical basis for the selection of structural parameters of metal fiber felt filter material, and has important research value.

Data analysis on tokamak plasmas is mainly based on various diagnostic systems, which are usually modularized and independent of each other. This leads to a large amount of data not being fully and effectively exploited so that it is not conducive to revealing the deep physical mechanism. In this work, Bayesian probability inference with machine learning methods have been applied to the electron cyclotron emission and Thomson scattering diagnostic systems on HL-2A/2M, and the effects of integrated data analysis (IDA) on the electron temperature of HL-2A with Bayesian probability inference are demonstrated. A program is developed to infer the whole electron temperature profile with a confidence interval, and the program can be applied in online analysis. The IDA results show that the full profile of the electron temperature can be obtained and the diagnostic information is more comprehensive and abundant with IDA. The inference models for electron temperature analysis are established and the developed programs will serve as an experimental data analysis tool for HL-2A/2M in the near future.

Double tearing modes (DTMs), induced by double current sheet configurations or two neighboring rational surfaces with the same safety factor in tokamaks, are widely observed in solar, space, and fusion plasmas. In this paper, the evolution of DTMs without a guide field is investigated numerically using a hybrid model (electron fluid + ion PIC). The overall evolution processes of DTMs are qualitatively consistent with previous works using other models. The particle dynamics during the evolution of DTMs is analyzed in detail. Behaviors of ions and electrons present different characteristics around the reconnection region which gives rise to Hall effects producing the out-of-plane quadrupole magnetic field. In the explosive reconnection process with interactions between two DTMs islands, the asymmetric drive and the thin current layer feature lead to the emergence of secondary magnetic islands which develop with the late evolution of the DTMs.

With the rapid development of internal combustion engine technology and the widespread popularity of diesel locomotives, the exhaust pollution of internal combustion engines has become a factor that cannot be ignored in air pollution. Particulate matter in diesel engine exhaust is an important culprit in diesel engine exhaust pollution, the harm of which has been widely recognized. This paper introduces the hazards of particulate matter in diesel exhaust, and summarizes DPF for particulate emissions and the regeneration technology of DPF.

With the development of internal combustion engine technology, internal combustion engine has been widely used in automobile, ship, electric power and other industries due to its advantages of high power density, high heat utilization rate and good economic performance. This paper analysed the advantages, the development process and current situation of internal combustion engine technology, while the development trend of internal combustion engine technology is prospected. Internal combustion engine technology will get greater development in the future.

Ion beam figuring (IBF) is an advanced machining technology for high precise optical component. For brittle materials with high thermal expansion coefficient such as KDP crystal, thermal effect is an intractable problem due to the accumulative heat introduced by incident ions on optical surface. Asymmetrical heating induces rapid changes of thermal stress and once the thermal stress exceeds the mechanical strength, the component may crack or break. In this paper, the number of scanning rows was factorized to various combinations with times of scanning and the number of moving rows. Temperature field and thermal stress of each combination were simulated using finite element analysis software ANSYS. Comparing with the results, the much better combination was found. With optimized scanning path, peak of thermal stress is lower than that of traditional scanning path. Especially, peak of tensile stress on X-distance and Y-distance were reduced obviously. At last, a law for optimization was established: when times of scanning and the number of scanning rows are equal or approximately equal, the thermal stress appears lower.

KDP crystal is difficult to fabricate for high precision. because it is brittle soft and with high heat expansion. Magnetorheological finishing (MRF) has been used to machine KDP for high precision. However, iron powders are easily embedded into KDP surface. Ion beam figuring (IBF) can clean iron powders embedded and enhanced laser-induced damage resistance. However, the thermal effect introduced by incident ions is a headachy problem. Temperature fields have been calculated by finite element simulation and measured by experiments. Thereof temperature fields of optical component bombarded by low energy ion beam were estimated and this estimate method is proved to be correct and feasible by comparing results of finite element simulation and experiments. And then, thermal stress of KDP under ion beam irradiation was calculated and discussed. Distributions of temperature and stress on KDP surface are accordant with beam current distribution. Temperature and stress rise quickly under ion beam irradiation, while decreases rapidly without ion beam irradiation. Peaks of temperature and thermal stress tend to periodicity. The period corresponds the period of ion beam moving spasmodically and fleetly in Y direction. Tensile stresses are not visible at X/Y/Z direction, but compressive stress at X direction is larger obviously than that of Y/Z direction.

It is difficult for existing filtrate reducer to meet oilfield application requirements. Based on the molecular structure design principle of temperature-resistant vinyl copolymer, a quaternary copolymer filtrate reducer has been developed with VCAP, AMPS, DMDAAC and AM as monomers through water solution copolymerization using redox initiation system. The optimum synthesis conditions were as follows: the mole ratio of monomer was VCAP/AMPS/DMDAAC/AM=1:1:1:9, reaction temperature was 70°C, reaction time was 6 h, initiator mass ratio was 0.2% and total monomer mass ratio was 20%. The filtration loss of base slurry with 1wt% optimum synthetic product after aging at 150 °C for 16 h was 5.2 mL.

Capability to detect or track macrophages in vivo is important for developing macrophage-based therapies. Dispersed carbon nanotubes (CNTs) have been used for Raman labeling of cells and a top-down approach has been developed to fabricate disk-shaped microparticles for the same application. This study presents the first fabrication of disk-shaped microparticles termed microdevices containing densely packed CNTs and Raman labeling of macrophages with the microdevices. The fabrication is featured by the use of spray coating of CNTs to produce the microdevices. Raman detection of a single microdevice at a centimeter-scale working distance and the feasibility of using chemically modified CNTs for multiplexed Raman labeling were demonstrated. Macrophages were stably labeled with the microdevices by simply adding the microdevices to cultivated macrophages. The labeling slightly reduced viability of the macrophages and the labeled macrophages retained their ability to capture foreign particles. Moreover, Raman detection of a single macrophage was demonstrated. The microdevices promise to be useful for detection or tracking of macrophages in vivo as well as for other biomedical applications.

The currently allowable photoelastic modulator based Fourier transform spectrometer (PEM-FTS) retardation-amplitude is low, and spectral resolution is relatively poor. This paper presents a method for high retardation-amplitude whose PEM is based on microtrapezoidal photoelastic crystals and Herriott-PEM. The retardation-amplitude of the improved PEM is about 19 times larger than an ordinary PEM. The ultra-high speed infrared spectroscopy remote measurement prototype is designed based on high retardation-amplitude PEM. The best spectral resolution of the prototype is 4 cm−1, and the zero-crossing single sided interferogram scanning time is less than 5 µs.

Evaluations to quantify the precise targeting of template features and to select template sizes for retinal motion extraction were carried out using cross-correlation with a high speed line scanning ophthalmoscope (LSO) capable of 160 frames per second. The optimal template targeting was located on a retinal vessel pattern with vessel bifurcation or vessel features occupying approximately eighty percent of the template area preferred. The optimal template size for this LSO system was 80 x 80 pixels and it was able to extract retinal motion up to 300 deg s(-1) at a speed of 30 Hz. Although the optimized template size was a compromise between having enough image data on the retinal features to make matches reliably and have good temporal resolution, the optimal targeting of the template location and size described here was appropriate and effective in extracting retinal motion. In addition, the determination of cross-correlation templates could be applied to other images having similar properties; i.e., relatively small features of distinct gray levels on an otherwise fairly uniform background.

Ultra-high frequency motions of the retina severely affect the stabilization of images and result in significant imaging distortions. In this paper, a high speed line scanning quasi-confocal ophthalmoscope (LSO) capable of 160 frames per second was devised for generating stable undistorted retinal images. This technique resulted in minimal intra-frame motions, and a strip-based cross correlation algorithm with sub-pixel resolution was applied to extract retinal motions. Three retinal motion components at rates of up to 1600 Hz were clearly distinguished and extracted accurately for the first time using ophthalmic imaging methods. This was especially apparent for the fastest tremor and microsaccade movements that cannot be estimated from previously reported ophthalmic imaging instruments. Furthermore, these results were consistent with retinal motion characteristics obtained with optical lever methods, validating this technique. Actually, the LSO system has great potential to extract retinal motions, and some other tracking systems may be adopted to correct retinal motions in ophthalmic imaging modalities.

It is reported frequently that the new carbon phases may be harder than diamond (Wang et al 2004 Proc. Natl Acad. Sci. 101 13699 and Mao et al 2003 Science 302 425). However, the mechanism is still unclear. In this paper we systematically investigate the structural, electronic, and mechanical properties of the diamond polytypes using first-principles density functional calculations. The results show that the bulk modulus and shear modulus for the hexagonal form of diamond approach those of diamond, suggesting they might be hard and low compressibility materials. According to the semiempirical method for hardness based on the Mulliken overlap population, the hardnesses for hexagonal forms have been evaluated and compared to diamond. The results indicate that these phases are superhard. More importantly, the bonds in some specific directions of the hexagonal phases are harder than those in diamond, which may lead to the noticeable indentation marks on the diamond anvils observed in experiments.

Magnetostriction behaviour and magnetostriction hysteresis of the single crystal alloy Tb0.29Dy0.48Ho0.23Fe2 are investigated experimentally and theoretically. The oriented 1?1?0 single crystals of the magnetostrictive alloy Tb0.29Dy0.48Ho0.23Fe2 are successfully prepared by the optical floating zone melting method. The single crystals are characterized by optical metallography, x-ray diffraction and x-ray Laue back-reflection measurement. The giant magnetostrictive properties are achieved in a wide operating temperature range from ?60 to 80??C. The calculated magnetostriction of the present alloy is reduced by only 6%, but the magnetostriction hysteresis (Wh) is reduced by more than 30%, compared with the traditional Terfenol-D giant magnetostrictive alloy. The magnetostriction behaviour is modelled using phenomenological theory. The rotation paths of magnetic domain moments are mathematically calculated and hence the resultant magnetostriction is obtained. The theoretical model of magnetostriction hysteresis Wh is proposed and the intrinsic factors of Wh are determined, which can well explain the pre-stress and temperature dependence of magnetostriction hysteresis.