核能制氢与高温气冷堆

氢是环境友好的能源载体,利用核能制氢引起了广泛的研究兴趣。本文对核能制氢的工艺,包括甲烷蒸气重整、高温电解和热化学循环进行了综述;提出了制氢过程对反应堆的要求,并介绍了高温气冷堆用于核能制氢的优势。     

CPE工艺生产小直径薄壁无缝钢管的优势

介绍了国内外ＣＰＥ新型顶管机组的概况，对比分析了ＣＰＥ机组与连轧管机组生产热轧小直径无缝钢管的技术经济指标。ＣＰＥ工艺生产小直径薄壁管具有一定的优势，可以作为国内中小轧管厂技术改造选择方案之一。     

模块式高温气冷堆核能系统二回路流体网络控制特性分析

针对模块式高温气冷堆（MHTGR）核能系统二回路流体网络进行非线性建模,研究管路动力学特性及网络拓扑结构特性,建立了微分-代数模型,设计了模块质量流量和汽机主蒸汽压力的调控方案。在MATLAB/Simulink环境下对模型进行标准化封装,以高温气冷堆核电站示范工程（HTR-PM）为例进行二回路流体网络的仿真。结果表明,模型有效地反映了系统二回路流体网络的非线性特性,设计的控制器使得模块流体质量流量和汽机主蒸汽压力有效地收敛于参考值,各项控制指标均高于控制要求。设计的仿真平台可为实际工程调控中积分时间系数的选择、拥有更多模块数量的高温气冷堆核能系统二回路流体网络的调控等提供试验仿真测试。     

Achievement of Reactor-Outlet Coolant Temperature of 950°C in HTTR

A High Temperature Gas-cooled Reactor (HTGR) is particularly attractive due to its capability of producing high-temperature helium gas and to its inherent safety characteristics. The High Temperature Engineering Test Reactor (HTTR), which is the first HTGR in Japan, achieved its rated thermal power of 30 MW and reactor-outlet coolant temperature of 950°C on 19 April 2004. During the high-temperature test operation which is the final phase of the rise-to-power tests, reactor characteristics and reactor performance were confirmed, and reactor operations were monitored to demonstrate the safety and stability of operation. The reactor-outlet coolant temperature of 950°C makes it possible to extend high-temperature gas-cooled reactor use beyond the field of electric power. Also, highly effective power generation with a high-temperature gas turbine becomes possible, as does hydrogen production from water. The achievement of 950°C will be a major contribution to the actualization of producing hydrogen from water using the high-temperature gas-cooled reactors. This report describes the results of the high-temperature test operation of the HTTR.     

Thermodynamic and Economic Analyses of HTGR Cogeneration System Performance at Various Operating Conditions for Proposing Optimized Deployment Scenarios

Several potential deployment scenarios of high-temperature gas reactor (HTGR) cogeneration systems for the simultaneous production of hydrogen and electricity have been proposed recently. They can operate under different conditions and thereby satisfy different hydrogen and electricity demand scenarios, but their performance must be studied to demonstrate thermodynamic feasibility and economic profitability to attract sufficient investment for their deployment. Therefore, this study uses exergy analysis and exergybased costing analysis methods to analyze HTGR cogeneration system performance thermodynamically and economically over the entire range of potential operating conditions by calculating performance indicators, exergy efficiency, and the specific cost per unit product. Furthermore, three optimized deployment scenarios with high performance for satisfying three different hydrogen demand scenarios are proposed based on the analysis results. The proposed three deployment scenarios show that the HTGR cogeneration system is thermodynamically efficient and economically competitive compared with other hydrogen and electricity generation systems. The feasibility of exergy analysis and exergy-based costing analysis methods for analyzing the HTGR cogeneration system so as to propose optimized deployment scenarios is demonstrated by the obtained findings practically.     

一种应用于小型永磁同步风力发电系统的简单控制方法

提出了一种应用于小型风力发电系统的简单控制方法,该系统采用永磁同步发电机,利用廉价的二极管桥式电路整流,并增加了一个Boost电路,可以通过调节其占空比来控制功率的输出,因此简化了整个发电系统并大大降低了成本。     

A review of integration strategies for solid oxide fuel cells

Due to increasing oil and gas demand, the depletion of fossil resources, serious global warming, efficient energy systems and new energy conversion processes are urgently needed. Fuel cells and hybrid systems have emerged as advanced thermodynamic systems with great promise in achieving high energy/power efficiency with reduced environmental loads. In particular, due to the synergistic effect of using integrated solid oxide fuel cell (SOFC) and classical thermodynamic cycle technologies, the efficiency of the integrated system can be significantly improved. This paper reviews different concepts/strategies for SOFC-based integration systems, which are timely transformational energy-related technologies available to overcome the threats posed by climate change and energy security.     

THETRIS: A micro-scale temperature and gas release model for TRISO fuel

The dominating mechanism in the passive safety of gas-cooled, graphite-moderated, high-temperature reactors (HTRs) is the Doppler feedback effect. These reactor designs are fueled with submillimeter-sized kernels formed into tristructural-isotropic (TRISO) particles that are imbedded in a graphite matrix. The best spatial and temporal representation of the feedback effect is obtained from an accurate approximation of the fuel temperature. Micro-scale models of TRISO particles are necessary in order to obtain accurate predictions during fast transients or when parameters internal to the TRISO are needed. Most accident scenarios in HTRs are characterized by large time constants and slow changes in the fuel and moderator temperature fields. In these situations, a meso-scale, or pebble- and compact-scale, solution provides a good approximation of the fuel temperature as the fission thermal energy transports out of the kernel and into the surrounding matrix with a much shorter time constant. Therefore, in most cases, the matrix can be assumed to be in quasi-static equilibrium with the kernels. These models, however, fail to provide accurate information on the state of the various components of the TRISO during the early stages of transients. Since the coated particles constitute one of the fundamental design barriers for the release of fission products, it becomes important to understand the transient behavior inside this containment system. An explicit TRISO fuel temperature model named THETRIS has been developed and incorporated into the CYNOD–THERMIX-KONVEK suite of coupled codes. The code includes gas-release models that provide a simple predictive capability of the internal pressure during transients. The new model yields similar results to those obtained with other micro-scale fuel models of TRISO particles, but with the added capability to analyze gas release, internal pressure buildup, and effects of a gap in the TRISO. Analysis of bounding benchmark transients yield good agreement with other codes in which the TRISO particles are modeled explicitly. In addition, a sensitivity study of the potential effects on the transient behavior of high-temperature reactors due to the presence of an inter-layer gap is included. Although the formation of a gap occurs under special conditions, its consequences on the dynamic behavior of the reactor can yield responses during fast transients that depart significantly from those in which no gap is present in the model. The new model was applied to an extreme (beyond design basis) scenario in order to observe the behavior of the fuel during a large prompt critical reactivity insertion. Although a large amount of fission energy was deposited rapidly into the fuel, the kernel temperature is shown to stay well below the melting point and the silicon carbide layer remained well below the temperature above which failure is expected to occur. The explicit treatment of the TRISO particle geometry leads to much lower estimations of power peaking during the transient and a greater degree of negative Doppler feedback.     

小口径直缝钢管焊接时阻抗器安装方式的改进

简要介绍了!10mm以下的小口径焊接钢管的直缝焊接生产工艺,高速焊接时阻抗器的安装方式。分析了传统工艺生产小口径焊接钢管时存在的问题和局限。通过改进阻抗器安装方式,小口径直缝焊接钢管的生产效率由过去的30m/min提高到60m/min,成材率由70%提到98%以上,效果明显。     

关于我国小型无缝钢管生产机组改造的探讨

以穿孔+冷拔生产工艺为代表的小型无缝钢管生产机组在我国有很长的历史,曾对国民经济发展做出过巨大贡献,但存在工艺技术装备落后,产品质量差,原料和能源消耗大,污染严重,劳动条件差等问题,因此改造小型无缝钢管生产机组势在必行。提出了Φ114mm(半)限动芯棒连轧管机组和Φ114mmCPE顶管机组是改造小型无缝钢管生产机组比较理想的机型选型建议。