Measurement of HL-2A NBI Beam Profile and Beam Power

To optimize the operation parameters of the beam line of NBI on HL-2A, features of the beam line, including the beam profile and the power deposited on components and injected into the tokamak plasma, were measured. The operational parameters of the four sources on the beam line were optimized with the monitor of the beam profile and beam power, and the transmission efficiency of the NBI injected power was therefore increased. A beam diagnostic system for the beam line of the NBI system on HL-2A as well as the diagnosed results was also presented.

Proposal of a Deuterium-Deuterium Fusion Reactor Intended for a Large Power Plant

This article looks for the necessary conditions to use Deuterium-Deuterium (D-D) fusion for a large power plant. At the moment, for nearly all the projects (JET, ITER…) only the Deuterium-Tritium (D-T) fuel is considered for a power plant. However, as shown in this article, even if a D-D reactor would be necessarily much bigger than a D-T reactor due to the much weaker fusion reactivity of the D-D fusion compared to the D-T fusion, a D-D reactor size would remain under an acceptable size. Indeed, a D-D power plant would be necessarily large and powerful, i.e. the net electric power would be equal to a minimum of 1.2 GWe and preferably above 10 GWe. A D-D reactor would be less complex than a D-T reactor as it is not necessary to obtain Tritium from the reactor itself. It is proposed the same type of reactor yet proposed by the author in a previous article, i.e. a Stellarator “racetrack” magnetic loop. The working of this reactor is continuous. It is reminded that the Deuterium is relatively abundant on the sea water, and so it constitutes an almost inexhaustible source of energy. Thanks to secondary fusions (D-T and D-He3) which both occur at an appreciable level above 100 keV, plasma can stabilize around such high equilibrium energy (i.e. between 100 and 150 keV). The mechanical gain (Q) of such reactor increases with the internal pipe radius, up to 4.5 m. A radius of 4.5 m permits a mechanical gain (Q) of about 17 which thanks to a modern thermo-dynamical conversion would lead to convert about 21% of the thermal power issued from the D-D reactor in a net electric power of 20 GWe. The goal of the article is to create a physical model of the D-D reactor so as to estimate this one without the need of a simulator and finally to estimate the dimensions, power and yield of such D-D reactor for different net electrical powers. The difficulties of the modeling of such reactor are listed in this article and would certainly be applicable to a future D-He3 reactor, if any.

Dynamic analysis of a rotating tapered cantilever Timoshenko beam based on the power series method

The mathematical modeling of a rotating tapered Timoshenko beam with preset and pre-twist angles is constructed. The partial differential equations governing the six degrees, i.e., three displacements in the axial, flapwise, and edgewise directions and three cross-sectional angles of torsion, flapwise bending, and edgewise bending, are obtained by the Euler angle descriptions. The power series method is then used to inves- tigate the natural frequencies and the corresponding complex mode functions. It is found that all the natural frequencies are increased by the centrifugal stiffening except the twist frequency, which is slightly decreased. The tapering ratio increases the first transverse, torsional, and axial frequencies, while decreases the second transverse frequency. Because of the pre-twist, all the directions are gyroscopically coupled with the phase differences among the six degrees.

Preliminary Research Results for the Generation and Diagnostics of High Power Ion Beams on FLASH II Accelerator

The preliminary experimental results of the generation and diagnostics of high power ion beams on FLASH II accelerator are reported. The high-power ion beams presently are being produced in a pinched diode. The method for enhancing the ratio of ion to electron current is to increase the electron residing time by pinching the electron flow. Furthermore, electron beam pinching can be combined with electron reflexing to achieve ion beams with even higher efficiency and intensity. The anode plasma is generated by anode foil bombarded with electron and anode foil surface flashover. In recent experiments on FLASH II accelerator, ion beams have been produced with a current of 160 kA and an.energy of 500 keV corresponding to an ion beam peak power of about 80 GW. The ion number and current of high power ion beams were determined by monitoring delayed radioactivity from nuclear reactions induced in a 12C target by the proton beams. The prompt 7-rays and diode bremsstrahlung X-rays were measured with a PIN semi-conductor detector and a plastic scintillator detector. The current density distribution of ion beam were measured with a biased ion collector array. The ion beams were also recorded with a CR-39 detector.

Analysis of Power Distribution on Beamline Components at Different Neutralization Efficiencies on NBI Test Stand

Neutral beam injection is recognized as one of the most effective means for plasma heating. According to the research plan of the EAST physics experiment, two sets of neutral beam injector（4–8 MW, 10–100 s） were built and operated in 2014. Neutralization efficiency is one of the important parameters for neutral beam. High neutralization efficiency can not only improve injection power at the same beam energy, but also decrease the power deposited on the heat-load components in the neutral beam injector（NBI）. This research explores the power deposition distribution at different neutralization efficiencies on the beamline components of the NBI device. This work has great significance for guiding the operation of EAST-NBI, especially in long pulse and high power operation, which can reduce the risk of thermal damage of the beamline components and extend the working life of the NBI device.

MECHANICAL VIBRATIONAL POWER FLOW IN BEAM-PLATE ASSEMBLIES

The vibrational power flow in the beam-plate assemblies and then with the isolators is investigated using analytical ' power flow' approach based on the some concepts of mechanical mo- bility and structural dynamics. Theoretical expressions of the power flow in the structures are given and examined. The numerical results of the expressions are good agreements with the measuring re- sults obtained by the technique of vibration intensity. On the basis of these results, possible ways of reducing the vibrational power flow in the structures are suggested .

Long-pulse power-supply system for EAST neutral-beam injectors

The long-pulse power-supply system equipped for the 4 MW beam-power ion source is comprised of three units at ASIPP（Institute of Plasma Physics, Chinese Academy of Sciences）： one for the neutralbeam test stand and two for the EAST neutral-beam injectors（NBI-1 and NBI-2, respectively）. Each power supply system consists of two low voltage and high current DC power supplies for plasma generation of the ion source, and two high voltage and high current DC power supplies for the accelerator grid system. The operation range of the NB power supply is about 80 percent of the design value, which is the safe and stable operation range. At the neutral-beam test stand, a hydrogen ion beam with a beam pulse of 150 s, beam power of 1.5 MW and beam energy of 50 ke V was achieved during the long-pulse testing experiments. The result shows that the power-supply system meets the requirements of the EAST-NBIs fully and lays a basis for achieving plasma heating.

Discharge Characteristics of Large-Area High-Power RF Ion Source for Positive and Negative Neutral Beam Injectors

A large-area high-power radio-frequency（RF） driven ion source was developed for positive and negative neutral beam injectors at the Korea Atomic Energy Research Institute（KAERI）. The RF ion source consists of a driver region, including a helical antenna and a discharge chamber, and an expansion region. RF power can be transferred at up to 10 kW with a fixed frequency of 2 MHz through an optimized RF matching system. An actively water-cooled Faraday shield is located inside the driver region of the ion source for the stable and steady-state operations of high-power RF discharge. Plasma ignition of the ion source is initiated by the injection of argongas without a starter-filament heating, and the argon-gas is then slowly exchanged by the injection of hydrogen-gas to produce pure hydrogen plasmas. The uniformities of the plasma parameter,such as a plasma density and an electron temperature, are measured at the lowest area of the driver region using two RF-compensated electrostatic probes along the direction of the shortand long-dimensions of the driver region. The plasma parameters will be compared with those obtained at the lowest area of the expansion bucket to analyze the plasma expansion properties from the driver region to the expansion region.

Incoherent and coherent beam combination for master oscillator/power amplifier system with stimulated Brillouin scattering mirror

In this paper, we studied incoherent and coherent beam combining for the master oscillator/power amplifier （MOPA） system with stimulated Brillouin scattering （SBS） mirror. Optic field intensity distributions in the near and far field are numerically calculated for the two kinds of system. The results show that good beam quality in the far field could be obtained. It provides a theoretical basis for experimental research in the future.

Power-Effective in the Cell Sectorization Using Wide-Beam and Narrow-Beam for Multi-hop Relay Network

Multi-hop relay is a significant topic in the wireless communication and it is provisioned in the 802.16j standards.At present,the major research on multi-hop relay is focused on the capacity,coverage,coordination,throughput,etc.But in this paper,a new concept about power-effective was discussed.Then,two power-effective coverage extension methods using two sectorized cellular approaches were introduced,i.e.,the widebeam three sector cell(WBTC) and the narrow-beam three sector cell(NBTC).Under such topologies,the consumption of power and optimal numbers of base stations(BSs) and relay stations(RSs) with respect to various user traffic densities were investigated.Finally,it is found that the performance of WBTC is better than NBTC.

Electron Beam Desulfurization Project of Chengdu Cogeneration Power Plant Started Construction - A new cooperation in environment protection between China and Japan

On March 25 1996, the electron beam flue gas desulfurization demonstration project of Chengdu Cogeneration Power Plant started formal construction This is at present the largest electron beam desulfurization project in power plants in the world, and is jointly constructed by Sichuan Electric Power Bureau and the EBARA Works of Japan, This is an important cooperation project in environment protection between

Simulation on control of beam halo-chaos by power function in the hackle periodic-focusing channel

The K-V beam through a hackle periodic-focusing magnetic field is studied using the particle-core model. The beam halo-chaos is found, and a power function controller is proposed based on mechanism of halo formation and strategy of controlling halo-chaos. Multiparticle simulation was performed to control the halo by using the power function control method. The results show that the halo-chaos and its regeneration can be eliminated effectively. We also find that the radial particle density evolvement is of uniformity at the beam’s centre as long as appropriate parameters are chosen.

Control of Beam Halo-Chaos by Fraction Power-Law Function in Hackle Periodic-Focusing Channel

The Kapchinsky Vladimirsky(K-V)beam through a hackle periodic-focusing magnetic field is studiedusing the particle-core model.The beam halo-chaos is found,and an idea of fraction power-law function controller isproposed based on the mechanism of halo formation and the strategy of controlling halo-chaos.The method is appliedto the multi-particle simulation to control the halo.The numerical results show that the halo-chaos and its regenerationcan be eliminated effectively by using the fraction power-law function control method.At the same time,the radialparticle density is uniform at the beam's center as long as the control method and appropriate parameter are chosen.

高功率微波大口径相控阵天线拍波辐射方法研究

相控阵天线是未来高功率微波辐射系统的重要形式之一,是当前研究的热点。为了获得超高等效全向辐射功率,高功率微波天线均为大口径形式。而大口径相控阵天线在辐射高功率微波拍波过程中,存在波束分裂、增益下降问题。针对该问题,本文提出了一种大口径相控阵天线拍波辐射结构,采用“子阵-面阵”两级馈电形式,解决了拍波辐射过程中波束分裂问题,有效提高了高功率微波系统的综合性能。该方法极大地节约了移相器数量,节省了系统成本,降低了系统复杂度,有利于实现高功率微波系统的小型化,提高系统的可靠性。

一种高功率微波宽带紧耦合偶极子阵列天线

提出了一种新型高功率微波宽带紧耦合偶极子阵列天线。在常规的紧耦合偶极子阵列天线的基础上,该阵列天线通过采用全金属结构设计、天线匹配层和密封层一体化设计以及调节天线结构的手段,获得了宽带高功率性能。仿真结果显示,在0.8~4.0 GHz的范围内,天线未扫描时的驻波比小于2;在16 mm×32 mm单元尺寸内和1个大气压的SF6气体中,功率容量达到0.12 MW;以该单元天线组成10×10阵列,100个单元总尺寸仅为160 mm×320 mm,在1个大气压的SF6气体中,功率容量可以达到12 MW,另外,该天线可实现45°的宽角扫描。该阵列天线的提出为实现高功率微波宽带天线的宽频带、大角度扫描、紧凑化、小型化以及低剖面化提供了参考。

基于DIABEAM法的电子束能量密度测试分析

为了充分发挥电子束焊接技术在航空航天领域的作用,对反映束流品质的关键因素—电子束能量密度开展了研究;基于法拉第传感原理,通过DIABEAM测试法对真空电子束焊机电子束能量密度分布进行测试分析;结果表明:电子束能量密度分布呈非对称的近高斯分布,随着聚焦电流的增加,电子束能量密度趋于发散分布,达到焦点状态时dP90区域内电子束能量密度均值最高;电子束能量密度峰值随着灯丝加热电流增加而增加,但受灯丝尺寸等因素的影响,灯丝加热电流达到稳定值后能量密度分布不变。

抽油机井恒功率变频控制系统研究

抽油机作为陆上油田最重要的机械采油装备之一,近年来已发展出一系列的变频节能技术,但其研究主要集中在硬件方面,缺乏相关基础理论,导致现场应用普适性差,应用效果参差不齐。为此,研究有杆泵变频测控机理,优选了主要部件,对测试数据提出了要求,形成了有杆泵抽油变频控制系统。构建BP神经网络系统对正常井和漏失、柱塞碰泵、气体影响等异常井进行识别,分类提出变频计算模型:考虑负扭矩和抽油机冲次界限等建立了正常井恒功率变频计算模型,实例对比分析了变频后抽油机速度、加速度变化规律,产液量一定时,负功功率和有功功率分别下降了65%和44%。建立了上行程漏失的异常井变频计算模型,针对性地提高上行程冲次,形成“上快下慢”运行模式。实例计算表明:该系统缩短上行程时间2.6 s,较好地解决有杆泵上行程漏失和变频节能的问题。研究成果可为抽油机变频技术提供理论支持,对油田节能和提产具有指导意义。

轻型多旋翼无人机激光供能系统优化设计

传统无人机电池的能量密度有限,限制了其飞行时间,激光供能系统可以延长无人机的续航能力。提出轻型多旋翼无人机激光供能接收阵列和扩束准直系统的优化设计方法,通过Matlab和Simulink联合仿真,对激光供能系统的传输功率损耗进行量化分析,将激光传能过程中的光伏阵列设计半径和初始光斑束腰半径的比值定义为缩放因子,将总传能效率细化为大气传输效率、截断效率、高斯填充效率和光电转换效率。以悬停姿态下的轻型多旋翼无人机为基础工况,进行详细的设计计算。结果显示,在给定光伏阵列设计半径和传输距离时,缩放因子存在最优值,光伏阵列设计半径对远距离传能效率有较大影响,随着传能距离的增加,截断效率下降成为主导因素。

一种旋转移相式高功率微波反射阵列天线

利用旋转移相技术的几何相位调控方法,提出一种基于传输相位差概念的波束扫描高功率微波反射阵列天线。电磁仿真结果表明,所设计的三叉戟形反射阵列天线单元工作于9.5~10.5 GHz,在0~40°入射角度下具有360°范围内的线性相位调控能力,真空条件下的功率容量达到1.11 GW。采用该单元设计了半径为200 mm的圆形口径反射阵列天线,并使用全波仿真软件进行验证,利用口径相位分布的可重构特性,所设计的反射阵列天线可以实现±40°范围内的波束扫描。在10 GHz时,波束扫描过程中的增益下降小于1.7 dB,最大增益达到31.1 dBi,对应口径效率为73.42%,最低口径效率超过50%,副瓣电平和轴比始终低于-18.7 dB和1.6 dB。