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液态铅铋合金是加速器驱动次临界系统(ADS)中散裂靶兼冷却剂的主要候选材料。氧浓度是影响液态铅铋合金(LBE)对结构材料腐蚀的关键因素,而氧传感器是实现液态铅铋合金中氧浓度精确测量的重要部件,本研究设计研制了一种液态铅铋系统氧传感器并基于自主研制的高温液态铅铋合金氧测控预研平台,初步开展了氧饱和LBE中的氧浓度测量实验。实验结果显示,300~400℃的氧饱和LBE中,氧传感器的电压信号(E)随温度(T)变化的实验曲线与理论曲线变化趋势相吻合;相对于300℃T350℃温度范围,氧传感器在350℃T400℃范围内的测量性能更好,仪器本身的系统误差约为17mV。 相似文献
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铅铋合金(Lead-Bismuth Eutectic,LBE)是加速器驱动次临界系统主选冷却剂材料之一,其热工流量测量面临高温、强腐蚀等苛刻环境。电磁流量计(Electromagnetic flow-meter,EMFM)是目前国际上用于铅铋流量测量的主选设备之一。研究发现,铅铋电磁流量计的标定技术对于其准确测量具有重要作用。本文基于PREKY铅铋技术预研实验平台,对自主研制的高温铅铋电磁流量计进行了标定实验与分析。在温度为350oC、流量为3.8–4.5m3?h-1的工况下,获得了液态铅铋电磁流量计的标定公式。标定公式计算值与实验值之间的误差范围是-4.9%–5.9%。 相似文献
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液态铅铋合金(Lead-Bismuth Eutectic,LBE)是加速器驱动次临界系统(Accelerator driven subcritical,ADS)重要的散裂靶材料和冷却剂候选材料,其热力学物理性质是ADS研发过程中必须解决的基础问题。通过对已有定律的推算,得出液态铅铋合金熔沸点、密度、比热容、粘度、热导率的热物性公式;并拟合了其他学者的实验研究数据,得出计算铅铋物性的拟合公式。通过对比分析可知:拟合公式与已有定律推算公式趋向一致,吻合较好;且拟合公式更趋近实验值,精确度高,最大偏差不超过1%。 相似文献
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钱燕悦 《中国原子能科学研究院年报》2007,(1)
完成了铅铋合金综合试验装置(TCTL)的初步设计方案。
装置的总设计功率为500kW,为中等规模强迫流动的综合实验装置,由铅铋合金回路、除气系统、覆盖气体系统、冷却水系统、氧控制系统和数采和控制系统及供配电系统等组成。流动介质为纯度高于99.5%的铅铋合金,其中铅含量44.5%,铋含量55.5%。 相似文献
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对于具有独立回路冷却液态铅铋(Liquid Lead-bismuth Eutectic,LBE)散裂靶的加速器驱动的次临界系统(Accelerator Driven Sub-critical System,ADS),高能质子束流辐照靶体产生的散裂产物进入管道后,会持续释放光子,会对靠近流动管道的工作人员造成辐射损伤。本文利用高能粒子输运程序Fluka计算散裂靶的散裂产物累积产额,然后利用放射性衰变计算程序Origen2计算散裂产物释放的光子强度及分群能谱,最后利用Fluka进行流动管道内光子源项的屏蔽计算。对一种典型的Y型LBE有窗靶进行的流动管道屏蔽计算结果表明,参照GB18871-2002职业性放射性工作人员年剂量当量限值20 m Sv的标准,若使用铅作为屏蔽材料,流动管道的管壁应该加厚20 cm。本文工作可为ADS系统LBE有窗靶的回路屏蔽设计提供参考。 相似文献
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《原子能科学技术》2015,(Z1)
在中国铅基反应堆(CLEAR)换热器管道破口(SGTR)事故工况下,二回路高压水可能会直接与一回路铅铋共晶合金(LBE)接触,导致水/蒸汽混合物的急速沸腾,甚至发生蒸汽爆炸,从而危及反应堆的安全。为研究水与熔融LBE接触界面间的沸腾传热与蒸汽爆炸现象及机理,本文通过熔融LBE/水直接接触反应实验平台,依托高速摄像机记录熔融LBE入水爆炸或碎化过程。实验分析了LBE温度(250~500℃)、水温(25~80℃)对熔融LBE碎化行为的影响。结果显示,随着熔融LBE温度或水温的升高,LBE碎化质量中位粒径呈减小趋势;当熔融LBE与水接触界面温度大于水的均相成核温度时,蒸汽爆炸现象更易发生,碎化现象更明显。 相似文献
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Corrosion and precipitation of corrosion products at an electrode of an electro-magnetic flow meter and in a narrow channel of an electro-magnetic pump (EMP) for lead bismuth (Pb-Bi) flow was investigated by means of metallurgical analysis. The roughened surface of inlet pump core at the entrance of EMP flow channel was observed, which indicated the occurrence of the so-called corrosion/erosion. In the same time, corrosion products were precipitated on the surface of the electrode and the outlet pump core. Localized corrosion/erosion and precipitation of corrosion products were observed by means of SEM/EDX analysis for their cross sections. The surface condition was different from each other depending on the place. The precipitation products were made of double-layers, that is, an outer layer and an inner layer. The inner layer (diameter range of 0–20 μm) contained Fe in the fraction of 99wt%, and the outer layer (diameter range of 20–40 μm) contained Pb-Bi in the fraction of 10wt%. The double layer structure might be caused by difference of precipitation period. These lumps of the precipitation products could be the cause of the channel plugging. 相似文献
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Lead and the Pb-Bi eutectic (Pb 55.9 at.%) have been modeled by a n-body potential derived from a second moment approximation of a tight binding Hamiltonian. The thermal behavior of the two systems in the liquid phase has been reproduced and relevant structural parameters have been evaluated and compared with experimental data. The diffusion coefficients and the activation energy for diffusion have been also evaluated. 相似文献
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Abdul-Majeed Azad 《Journal of Nuclear Materials》2005,341(1):45-52
Liquid metals such as Bi and Pb and Pb-Bi eutectic alloy are serious contenders for use as coolant in LMFBRs in lieu of sodium due to a number of attractive characteristics (high density, low moderation, low neutron absorption and activation, high boiling point and poor interaction with water and air, etc.). Analysis of hypothetical accidents is of relevance to predict the catastrophe involving loss of coolant accident (LOCA) in LMFBRs. One key parameter to take into account is the critical temperature data of the liquid metals for reactor safety analysis. This communication reports the application of a theoretical model called internal pressure approach to predict the critical temperature (Tc) of the LBE alloy for the first time. 相似文献
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This research project deals with the feasibility studies concerning the construction of an hybrid reactor for the transmutation of long-lived radioactive wastes. In this context, the liquid lead-bismuth eutectic (LBE) is considered to be a good candidate for the spallation target material needed for the neutrons production necessary to the transmutation. In this hybrid reactor, the LBE, which is enclosed in a T91 (Fe-9%Cr) steel container, can induce corrosion concerns. If the oxygen content dissolved in Pb-Bi is higher than the needed content for magnetite formation, corrosion proceeds by oxidation of the steel. Previously, specific results were reported, obtained in stagnant liquid LBE at 470 °C. An analytical model taking into account the oxide layer structure has been carried out. It involves iron, oxygen and chromium bulk diffusion and diffusion via preferential paths such as liquid lead-bismuth nano-channels incorporated in the oxide layer structure and grain boundaries. In this paper, experimental results on corrosion kinetics, obtained at different temperatures with different percentages of lead in the lead-bismuth alloy, are presented. The model, adapted to the different experimental conditions, is compared to these kinetics and to experimental points coming from the literature at different temperatures in LBE, in pure lead and in pure bismuth. 相似文献
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The presence of micro-cracks at the surface of a ferritic-martensitic steel is known to favour its embrittlement by liquid metals and thus decrease the mechanical properties of the structural materials. Unfortunately, conventional fracture mechanics methods cannot be applied to tests in liquid metal environment due to the opaque and conducting nature of the LBE. Therefore new methods based on the normalization technique for assessment of plain strain fracture toughness in LBE were examined. This paper discusses the assessment of the plain strain fracture toughness of T91 steel in liquid lead bismuth environment at 473 K, tested at a displacement rate of 0.25 mm min−1 and makes the comparison with results obtained in air at the same temperature and displacement rate. Although there is a decrease of the fracture toughness by 20-30% when tested in LBE, the toughness of the T91 steel remains sufficient under the tested conditions. 相似文献
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Dissolved oxygen control and monitoring implementation in the liquid lead-bismuth eutectic loop: HELIOS 总被引:1,自引:0,他引:1
A 12 m tall LBE coolant loop, named as HELIOS, has been developed by thermal-hydraulic scaling of the PEACER-300MWe. Thermo-hydraulic experiment and materials test are the principal purposes of HELIOS operation. In this study, an yttria stabilized zirconia (YSZ) based oxygen sensor that was hermetically sealed for long-term applications using the electromagnetically swaged metal-ceramic joining method, have been developed for high temperature oxygen control application over a long period of time. The rugged electrode design has been calibrated to absolute metal-oxide equilibrium by using a first principle of detecting pure metal-oxide transition using electrochemical impedance spectroscopy (EIS). During the materials tests in HELIOS, dissolved oxygen concentration was administered at the intended condition of 10−6 wt% by direct gas bubbling with Ar + 4%H2, Ar + 5%O2 and/or pure Ar while corrosion tests were conducted for up to 1000 h with inspection after each 333 h. During the total 1000 h corrosion test, oxygen concentration was measured by oxygen sensor. The result confirmed that the direct gas bubbling method is a viable and practical option for controlling oxygen concentration in large loops including HELIOS. 相似文献
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Since the 1950s, liquid lead (Pb) and lead-bismuth eutectic (Pb-Bi) have been studied in the USA, Canada and in the former-USSR as potential coolants for nuclear installations due to their very attractive thermophysical and neutronic properties. However, experimental data on the thermal properties of these coolants in the temperature range of interest are still incomplete and often contradictory. This makes it very difficult to perform design calculations and to analyse the normal and abnormal behaviour of nuclear installations where these coolants are expected to be used. Recently, a compilation of heavy liquid metal (HLM) properties along with recommendations for its use was prepared by the OECD/NEA Working Party on Fuel Cycle (WPFC) Expert Group on Lead-Bismuth Eutectic Technology. A brief review of this compilation and some new data are presented in this article. A set of correlations for the temperature dependence of the main thermodynamic properties of Pb and Pb-Bi(e) at normal pressure, and a set of simplified thermal and caloric equations of state for the liquid phase are proposed. 相似文献
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Xiu-Bo Liu Ge-Yan Fu Shuang Liu Shi-Hong Shi Xiang-Ming He Ming-Di Wang 《Nuclear Engineering and Design》2011,241(12):4924-4928
As a further step in obtaining high temperature wear and corrosion performances of a newly designed and laser cladded cobalt-free, nickel-based alloy coating (Ni-3) used for sealing surfaces of nuclear power valves, high temperature dry sliding wear behavior was characterized on a HT-1000 ball-on-disk tribometer at 360 °C, the hot corrosion test was conducted by plating Na2SO4 + K2SO4 mixed salt solution on the coating at 350 °C for 140 h. For comparison, the high temperature wear and corrosion resistance of the laser cladded Co-based Stellite06 and Fe-based Norem02 coatings were also investigated at the same testing conditions. It is found that the microhardness of the Ni-3 coating is about HV500 and close to Stellite06, but less than Norem02, the high temperature wear volume loss of Ni-3 coating is half of Norem02 and close to Stellite06. While during 350 °C hot corrosion test, the mass loss of Norem02 coating is the largest, Ni-3 coating is placed in the middle, Stellite06 coating shows the best hot corrosion resistance. Thus, the newly designed and laser cladded Ni-3 alloy coating appears to be the viable alternative material and technique for Co-free alloy, especially used in the nuclear valve sealing surfaces. 相似文献