混合堆FEB—E粒子抽除和氘氚回收系统的概要设计

实验混合堆FEB依靠偏滤器排出粒子及其携带的能量。排出的粒子包括聚变反应产物α粒子、等离子体表面相互作用产物杂质以及没能产生聚变反应的氘氚燃料粒子等。FEB－E粒子抽除和燃料回收循环系统的任务是抽除上述氦灰、杂质以及大量的没能产生聚变反应的氘氚燃料粒子等燃烧废气,以能实现有效的堆芯等离子体纯度控制和密度控制;同时将排出废气中没能产生聚变反应的氘氚燃料粒子分离、纯化和回收,即实现氘氚工艺处理。     

激光聚变靶中氘氚燃料的测量

用Si(Li)-S85低能X-射线谱仪系统测量简单爆推靶中氘氚燃料的含量。用内充气正比计数装置刻度了此谱仪系统的探测效率。其效率与玻璃球成份和壁厚有关。本系统的效率为10~5量级。根据氚含量及燃料的D/T比值,推算出靶内含氘量及氘氚燃料的总气压,并与气泡法测得的总气压进行了比较。最后对实验结果进行分析和讨论。     

托卡马克氘氚聚变堆中氚的二倍频ICRF加热物理分析

本文从准线性理论出发，导出了ＩＣＲＦ二倍频加热时对磁面平均的吸收功率密度的近似解析表达式，并指出了这一近似的适用范围。采用冷等离子体近似计算波的色散关系，利用ＥＰＰＡＣ程序求解二维时间相关Ｆｏｋｋｅｒ－Ｐｌａｎｃｋ方程，分析了氚的二倍频加热。对于典型的氘氚聚变反应堆参数，计算了等离子体各组分温度随时间的变化及氚的分布函数随时间的演化，并分析了氚的非麦氏分布及相关的氘氚聚变反应率。结果表明，对于反应堆规模的等离子体来说，ＩＣＲＦ加热只在温度不太高时才导致明显的非麦氏分布及氘氚聚变反应率提高；在等离子体温度提高到约１０ｋｅＶ后，反应率不再有明显的提高     

钯膜分离氢氦过程中浓差极化现象

根据设计,未来聚变堆等离子体排灰气中除了氘氚还含有以惰性气体为主的杂质气体,会在钯膜纯化氢同位素的过程中产生不容忽视的浓差极化现象,降低排灰气的处理效率。针对这一现象,以氢氦混合气为源项,研究了钯膜在分离氢氦过程中浓差极化对渗氢性能的影响,利用极化系数对浓差极化的程度进行评估,并考察了渗氢驱动力、氦气浓度以及原料气流量对极化系数的影响。结果表明:在150,300,450kPa时的H2/He选择性分别为37 460,18 347和7935,可以看出钯膜致密性良好;浓差极化系数随着渗氢驱动力和氦气浓度的升高而增大,对于原料气流量的变化则呈现相反趋势。     

快重离子束实现点火的可行性

采用蒙特卡罗方法计算了低温下C,Si,Ar,Au和U等多种重粒子在等物质的量氘氚等离子体密度1000 g/cm3、热斑直径50 m中的电子能量损失,不同点火形式下入射能量和作用时间,以及燃料约束时间为20 ps条件下的束流强度。通过对数据的分析研究了这些重粒子辐照实现氘、氚燃料快点火的可能性。结果表明,重粒子束流加热等离子体实现快点火理论上可行,而且有一定的优势;较重的离子加热聚变等离子体的效果更好。重粒子束流加热等离子体到聚变温度需要的束流强度在MA左右;单个粒子的能量在GeV以上;相互作用时间为ps以下。     

基于温度梯度的ICF冷冻靶均化技术研究

惯性约束聚变(ICF)冷冻靶中氘氘(D2)、氘氚(DT)等燃料冰层在靶丸中的分布由靶丸所处的温度场决定。在氘氘冷冻靶中,垂直温度梯度引起的气-液界面张力梯度可以抵消重力作用,使氘氘液体在靶丸内均匀分布;然后在氘氘的三相点附近缓慢降温,可以实现燃料冰层的均化。在氘氘冷冻靶均化实验系统上,采用温度梯度结合制冷速率与制冷过程控制的方法,实现了1mm直径、30μm壁厚的辉光放电聚合物(GDP)靶丸中氘氘冰层的均化,对背光阴影图像中亮环位置进行分析表明:氘氘冰层的平均厚度为185.56μm,均匀度为80.2%,模数-功率谱曲线中模数2~100对应的内表面粗糙度为2.26μm。     

氢同位素交换催化剂制备及性能

聚变反应堆或聚变裂变混合堆氚工厂中,氘氚燃料回收和含氚废水、废气处理过程中,涉及液态水、汽态水和甲烷与氢气间的同位素交换反应,催化剂是实现这些反应的关键。     

LaNi4．25Al0．75合金吸放氚性能

在真空系统中对熔融法制备的LaNi4.25Al0.75合金的氘活化特性、吸放氚p-C-T曲线和不同温度下的吸放氚速率，以及材料吸附氚气与解析氚气的纯度进行了研究，以考核该合金氚操作与贮存性能。     

Z箍缩驱动聚变-裂变混合堆氚燃料循环系统氚盘存量与氚自持初步分析

为研究氚自持条件,建立了Z-FFR氚分析模型,基于理论方程和氚平均滞留时间方法进行计算,得到稳态运行时排灰气处理系统、氚增殖提取系统、同位素分离系统、水去氚化系统的氚质量流分别为52.30,25.40,81.30,3.60 g/day,对应的氚盘存量为52.30,25.40,8.13,1.80 g。同时以氚质量流推导出氚自持判断条件,分析了设计参数能够满足氚自持要求,同时获得了燃烧效率、氚增殖率、提取效率与氚自持的互补关系,三者作为关键参数相互依存,于临界值、设计值、理想值之间分析了氚的自持情况。     

热电子与聚变等离子体相互作用模拟计算的误差分析

对惯性约束聚变(ICF)实验条件下热电子辐照聚变等离子体（DD,DT）的射程岐离和散射进行了分析。结果表明,射程岐离和散射随射程增加近似呈直线增加;射程岐离和散射大小与等离子质量有一定关系。在单能热电子入射下,散射是计算结果误差的主要来源,误差在5%以下,绝对数在数十MA。入射束流的电子完全沉积在热斑中的聚焦角度,在边沿点火方式中,氘等离子体中为20.64,氘氚等离子体中为21.8;在中心加热方式中,氘等离子体中为16.36,氘氚等离子体中为17.6,在技术上相对易于实现。     

LB simulation on soot combustion in porous media

Although diesel engines have an advantage of low fuel consumption in comparison with gasoline engines, several problems must be solved. One of the major concerns is that diesel exhaust gas has more particle matters (PM) including soot, which are suspected to be linked to human carcinogen. As one of the key technologies, a diesel particulate filter (DPF) has been developed to reduce PM in the after-treatment of exhaust gas. In this study, we conduct lattice Boltzmann (LB) simulation on combustion in porous media. Results show that the combustion reaction is well simulated to observe the decrease of soot attached to the porous wall. This information is indispensable for the better design of DPF, and LB method can be a good tool for combustion simulation in porous media.     

不同流场下进气对质子交换膜燃料电池性能的影响

流场的结构对于质子交换膜燃料电池(PEMFC)的水管理和气体的传递具有十分重要的影响,相关研究一直是燃料电池的研究热点与重点。本文以纯氧气和空气作为阴极氧化剂,通过电池的性能测试、极化曲线和电化学阻抗分析等原位实验,分析了气体的流动与传输、不同流场下的电流密度、入口反应气体浓度等条件对电池性能的影响。实验结果表明,提高氧气浓度可以获得更好的质子交换膜燃料电池性能和最小化活化损失,纯氧气、波状流场的使用效果随进气量的变化而有明显的变化。     

Pd-Ag膜电解浓缩氚的动力学模型及理论计算

建立了模拟Pd-Ag合金膜电解浓缩氚的过程和诸多电解参数的动力学模型。采用求解数学扩散方程的方法得到理论值,并与文献报道的实验数据进行比较。计算结果表明：氚在Pd-Ag膜上的吸附、解吸、浓缩等行为受到诸多条件的制约。在保证密封性能的前提下,对Pd-Ag膜电解槽体的要求是至少应包括有含氚水路循环、阳极气体消除和阴极扩散后氚再生3个组成部分,采取相匹配的级联技术可以提高分离效果;对电解参数的要求是采取尽可能高的电解液温度和稳定的OH^-浓度,合适的电流密度,合理的膜厚度、表面特征和Pd黑结合紧密。     

Characterization of nuclear tracks by positron annihilation and gas permeation

The application of polymeric membrane in combination with metallic films can be used for gas purification in particular for hydrogen where the molecular size is very small. The affinity of hydrogen to certain metals assists the flow of hydrogen, although it restricts the permeation of other gases. However, the flow rate is very small in dense membranes. Attempts have been made to generate nuclear tracks in polymeric membranes to control the gas flow. These tracks can be characterized by positron lifetime spectroscopy and gas permeation measurements. The long lifetime of ortho-positronium gives the estimate of size of the track-free volume of the order of 0.25 nm. The nuclear tracks can be modified by a chemical etching process. The chemical etching normally takes place from both sides of the membrane. When the etched pits from both sides meet, a rapid increase in gas permeation is observed. The size of the nano opening of the track has been observed for two different gases hydrogen and carbon dioxide, which have a molecular size of 0.2 and 0.4 nm, respectively.     

高时间分辨的聚变反应峰值时刻测量

聚变反应峰值时刻是表征惯性约束聚变热核反应的重要参数。在神光Ⅲ原型装置上利用新研制的具有高时间分辨的聚变反应历程测量系统对聚变反应时间过程进行了测量,通过引入时标光获得了对应不同碳氢（CH）烧蚀层厚度的聚变反应峰值时刻数据,测量结果表明:在当前的实验条件下,聚变反应峰值时刻落后入射激光0.7~1.0 ns,增加烧蚀层厚度或氘氚（DT）燃料气压均会导致聚变反应峰值时刻与入射激光间的相对延时增加。     

Review of proton conductors for hydrogen separation

There is a global push to develop a range of hydrogen technologies for timely adoption of the hydrogen economy. This is critical in view of the depleting oil reserves and looming transport fuel shortage, global warming, and increasing pollution. Molecular hydrogen (H₂) can be generated by a number of renewable and fossil-fuel-based resources. However, given the high cost of H₂ generation by renewable energy at this stage, fossil or carbon fuels are likely to meet the short- to medium-term demand for hydrogen. In view of this, effective technologies are required for the separation of H₂ from a gas feed (by-products of coal or bio-mass gasification plants, or gases from fossil fuel partial oxidation or reforming) consisting mainly of H₂ and CO₂ with small quantities of other gases such as CH₄, CO, H₂O, and traces of sulphur compounds. Several technologies are under development for hydrogen separation. One such technology is based on ion transport membranes, which conduct protons or both protons and electrons. Although these materials have been considered for other applications, such as gas sensors, fuel cells and water electrolysis, the interest in their use as gas separation membranes has developed only recently. In this paper, various classes of proton-conducting materials have been reviewed with specific emphasis on their potential use as H₂ separation membranes in the industrial processes of coal gasification, natural gas reforming, methanol reforming and the water–gas shift (WGS) reaction. Key material requirements for their use in these applications have been discussed.     

流道结构和几何尺寸对燃料电池性能影响的实验研究

流场板是质子交换膜燃料电池重要部件之一。本文对以氢气和氧气作为反应气体的质子交换膜电池的极化曲线进行了实验测定,研究了不同流场板结构、流场板深度和宽度对电池性能的影响．研究发现采用组合流道的电池性能最佳．     

Selective diagnostics of combustion processes in multi-burner boilers

The process of gas hydrocarbon combustion was tested in real (industrial) conditions on boilers with many burners. For key operation modes, the main regularities of emission from single flames were studied. The system of remote diagnostics was developed; it is suitable for selective monitoring of a single burner in the multi-burner configuration and supplies useful information for the operator about relative intensity of flames, oxygen, and hydrogen concentrations in flue gases. This information is valuable for optimization of gaseous fuel combustion. The equipment set was used in development of an automatic control system for processes at a heat station.     

Muon catalyzed fusion of deuterium-tritium at elevated densities

Calculations of the number of deuterium-tritium fusions a muon might catalyze in temperature and density conditions found in moderate fuel compressions are examined. Analytic models of muon catalyzed fusion reactions including muon sticking suggest that a deuterium-tritium fuel target with injected muons achieves an energetically viable number of fusions per muon only at fuel temperatures less than about 5 eV and fuel densities greater than 100 times LHD.     

Laminar burning velocity and ignition delay time for premixed isooctane–air flames with syngas addition

The effects of blending syngas in different proportions to isooctane on the laminar burning velocity and ignition delay time of the fuel–air mixture have been studied in SI engine relevant conditions. The syngas is assumed to be composed of 50% H₂ and 50% CO. Simulations have been carried out using a skeletal mechanism containing 143 species and 643 reaction steps. It has been found that the blending of syngas augments the laminar burning velocity of isooctane due to increase of the thermal diffusivity of the reactant mixture and alteration in the chemistry of the flame reactions. For the mixture of 30% isooctane/70% syngas, the laminar burning velocity and the ignition delay time values are very close to those corresponding to pure isooctane. Additionally, the effects of exhaust gas recirculation have been explored for the 30% isooctane/70% syngas–air flame. It is seen that the reduction in laminar burning velocity due to the dilution by the recirculated exhaust gas can be compensated by an increase in the unburnt gas temperature. The effect of the exhaust gas dilution on the ignition delay time of 30% isooctane/70% syngas–air mixture has been found to be negligible.