高放废物地质处置新疆雅满苏预选地段三维地质建模研究

利用三维地质建模软件Micromine和深探地学建模软件建立了雅满苏预选地段的三维可视化地质模型,直观地反映了该预选地段岩体、断裂的空间展布和相互关系等深部地质环境信息。基于所建立模型开展了三维剖切分析、对模型任意切割和开挖等一系列实用的可视化分析,为后续处置库预选地段的适宜性评价提供资料和技术支持。     

钻孔电视技术在三维地质建模中的应用

断层特征是岩体工程质量评价和三维地质建模的基础数据,但传统手段无法获得精确的深部断层产状。利用超声波钻孔电视技术可获得岩体深部断层的产状特征。基于钻孔电视技术和其他地质资料对中国高放废物地质处置地下实验室的推荐场址—甘肃北山新场花岗岩地段周边的断层特征进行研究,获得详实的断层特征数据,为推荐场址三维地质建模研究和地下实验室工程设计提供了参考数据。研究成果对区域基础地质研究具有重要指导意义。     

三维离散纵标方法在反应堆精细屏蔽计算中的应用研究

随着计算能力的发展,三维离散纵标方法(SN)已逐渐为反应堆辐射屏蔽计算的主流方法之一。本文就三维SN方法应用于反应堆的精细化屏蔽建模与分析的关键问题进行了研究,主要包括精细化几何建模、堆芯固定源模型的创建和数据库截面参数敏感性分析等内容。在此基础上,本文以典型的压水反应堆为对象,构建了精细的三维SN计算分析模型,以压力容器快中子注量率为算例,完整实现了反应堆的精细化三维SN建模与分析,并将三维SN结果和蒙特卡罗方法的计算结果进行了比较分析。对比结果表明,精细化三维SN方法具有较高的计算精度,验证了三维SN方法在反应堆精细屏蔽计算问题中的有效性和正确性。     

地下实验室施工期井巷地质编录技术方法研究

在高放废物地质处置地下实验室建设阶段,井巷地质编录是一项基础性的现场工作,可获得不同硐室的地质信息、查明场址区域内岩体与构造特征,其编录数据可为场址精细化三维地质建模与围岩长期稳定性分析提供基础资料,为工程开挖过程中的现场试验设计和未来地下实验室中的科研试验提供支撑。传统的地质编录方法,其编录目标、对象和内容等存在诸多方面的差异,通过借鉴国外地下实验室的编录经验,并参考了国内相关领域的编录标准和规范,结合北山地下实验室的工程特点,编制了一套适用于北山地下实验室的井巷地质编录技术方法。该方法不仅填补了我国在高放废物地质处置地下实验室井巷地质编录技术规范的空白,同时也可为地下工程的编录方法提供参考。     

北山地下实验室斜坡道三维地质建模研究

基于KANTAN 3D和SKUA-GOCAD软件,对北山地下实验室斜坡道围岩岩性、节理和断层分布特征等巷道编录资料进行深入解译和分析,探讨建模思路与方法,以期整合各种地质特征,建立直观、科学的地下实验室巷道尺度三维地质模型,为岩石力学分析提供几何框架与地质参数。结果显示：北山地下实验室斜坡道前460 m岩性相对单一,以花岗闪长岩和片麻状二长花岗岩为主;斜坡道构造建模主要从单节理、节理（蚀变）带和断层（带） 3个影响因素进行考量;节理总体走向以NNE向为主,倾向以SEE向为主,倾角集中在60°～90°之间;共发育4处节理蚀变带,规模小,未延伸至地表。随着地下实验室工程开挖和相关试验数据的不断丰富,对地下实验室斜坡道的地质建模方法和地质认识水平将不断提高,相关成果将为安全评价等研究提供重要基础。     

X射线计算机断层扫描成像在纺织技术中的应用

传统光学成像或扫描电镜成像作为微观结构的分析方法只能观测到材料外观形貌,难以实现材料内部结构的三维表征,在一定程度上限制了其在纺织领域中的应用。为促进三维电子计算机断层扫描（CT）技术在纺织领域的应用和发展,本文首先介绍X射线计算机断层扫描成像（XCT）在纺织应用上的测试设备、测试方式以及图像质量的影响因素;进一步综述XCT技术在织物内部结构表征、辅助建模预测织物性能（热传递性、压缩性）以及纱线研究等方面的应用进展;最后总结XCT技术在纺织应用上的优缺点,同时针对XCT在纺织领域中研究的匮乏,对未来XCT技术的潜在应用进行了展望。     

含水构造γ放射性特征及探测技术

利用天然放射性调查地下水资源,在近几年的实验应用中已取得了较好的地质效果。本文从野外应用实例出发,讨论了该技术的地质及地球物理基础、含水构造γ放射性特征及探测方法等方面的问题。     

反应堆蒙特卡罗程序RMC模型可视化功能开发

反应堆蒙特卡罗程序RMC采用构造实体几何技术(CSG),建模过程需要用户输入所有的曲面、栅元等几何单元,其文本形式的建模方法具有高效、精确的优势,但同时存在表现力差、易于引入错误等问题,模型可视化是一项重要功能。本文基于程序的几何定位功能,结合像素化图形技术,研究了RMC的模型可视化方法,开发了程序的画图模块,该模块支持模型的二维或三维、几何或材料信息的可视化显示。对画图功能进行了测试,验证了模型可视化的效果与意义。     

三维可视化技术在矿产资源勘探领域中的应用探讨

地质体三维可视化技术的研究是“数字勘探”领域的重要组成部分，本文针对矿产资源勘探数据的特点，研究了适合地质体信息三维可视化的体素模型和空间插值算法。基于交互式数据语言(IDL)，开发了三维数据可视化软件；该软件能够快速、准确地将地质体的空间展布形态以及物性特征展示出来。     

中国铀矿地质勘查信息化建设现状及“十四五”发展思路

"十三五"期间,中国铀矿地质勘查初步实现了数据采集、综合编图、三维建模等数字化。基于大数据、人工智能、云计算等新一代信息技术,按照"顶层谋划、分步实施,需求导向、注重实效,资源共享、保障安全,建用并举、引进技术"的原则,文章提出了"十四五"铀矿地质勘查信息化的发展思路、总体架构及重点任务,阐述了数据采集、数据汇聚、智慧勘查、决策支持、标准规范、基础设施等6个方面发展方向,为铀矿勘查"十四五"信息化建设提供参照和指引。     

精密数控高真空电子束焊机的研制

介绍了精密数控电子束焊机的结构、主要技术指标和特点，着重叙述了新型设备的设计原理、特点以及一些关键技术问题的解决方案。     

基于虚拟体积力动量源的燃料组件热工水力数值求解方法

针对计算流体力学（CFD）与三维精细化建模方法应用于反应堆燃料组件热工水力分析时普遍面临计算量较大和计算效率较低的问题,本文基于搅混翼对流场及温度场的阻流、导流、搅混与换热强化等方面的影响机理,通过建立搅混翼的虚拟体积力数理模型来考虑搅混翼对热工水力的影响。以两通道模型为研究对象,将虚拟体积力模型以动量源项的形式加入无翼片通道中,获得了带搅混翼通道的热工水力特性。该方法避免了直接对燃料组件中的复杂搅混翼结构进行贴体网格建模,可显著简化建模过程、降低计算量及提高计算效率。通过与实验数据及传统贴体网格建模结果的综合对比分析,验证了模型的有效性。研究结果表明：搅混翼对棒束通道流场及温度场的综合影响,可等效为结构对流体施加的某种作用力改变了流体质点运动规律,从而表现出特殊的热工水力现象;虚拟体积力动量源模型所计算的流速、压降及换热系数等关键热工水力参数,与实验数据及传统贴体网格计算结果吻合良好,并能适应不同流速工况。     

Deformation bounds for elastic-plastic solids within and out of the creep range

A bounding principle for elastic-perfectly plastic creeping and noncreeping structures subjected to mechanical and/or thermal loads varying below or above the shakedown limit is presented. This principle contains some free “perturbation functions” which, suitably chosen, enable it to specialize, so generating bounds on a variety of deformation measures (such as inelastic work dissipated within any portion of the body, inelastic strains and displacements), some of which are new results, others recover or generalize known results. The resulting bounding technique possesses a quite unified character which is useful for computational purposes. The concept of “pseudo-plastic” strain is shown to be crucial for the derivation of bounds applicable above the shakedown limit.     

Numerical Model of Radionuclide Migration in Geologic Media

A three-dimensional radionuclide migration model has been developed by using of the direct-simulation method. The phenomena taken into account are radioactive decay, convection and dispersion in the ground water and sorption and desorption in the geologic media. Decay chain is represented by particle's character change using decay probability. Smoothing method is proposed to make an even distribution of particles and to obtain the exact radioactive inventory. Numerical calculations of ²⁴⁵Cm decay chain and ²³⁴U decay chain in the single layered geologic media have been carried out, and reasonable results have been obtained in comparison with INTRACOIN study. Nuclide migration of ²³⁷Np decay chain in the three-layered geologic media were examined and shown graphically.     

Three-Dimensional Transport Calculation Method for Eigenvalue Problems Using Diffusion Synthetic Acceleration

A three-dimensional transport code “TRITAC” for solving eigenvalue problems in reactor cores has been developed on the basis of discrete ordinates method with the diffusion synthetic acceleration technique. The Larsen procedure for the diffusion synthetic acceleration method has been extended to three-dimensional geometry. With the procedure a spatially differenced diffusion synthetic equation has been derived and implemented in the TRITAC code. In the X-Y geometry the code yielded the same results as the TWOTRAN-II code. Three-dimensional eigenvalue problems for thermal and fast reactors have been solved and the computational time has been compared with that required for the three-dimensional discrete ordinates calculation with the rebalance acceleration technique.     

Advanced applications of boundary-integral equation methods

Numerical analysis has become the basic tool for both design and research problems in solid mechanics. The need for accuracy and detail, plus the availability of the high speed computer has led to the development of many new modeling methods ranging from general purpose structural analysis finite element programs to special purpose research programs. The boundary-integral equation (BIE) method is based on classical mathematical techniques but is finding new life as a basic stress analysis tool for engineering applications. This paper summarizes some advanced elastic applications of fracture mechanics and three-dimensional stress analysis, while referencing some of the much broader developmental effort. Future emphasis is needed to exploit the BIE method in conjunction with other techniques such as the finite element method through the creation of hybrid stress analysis methods.     

A bounding technique for dynamic plastic deformations of damped structures

A bounding principle for elastic-perfectly plastic creeping and noncreeping structures subjected to mechanical and/or thermal loads varying below or above the shakedown limit is presented. This principle contains some free “perturbation functions” which, suitably chosen, enable it to specialize, so generating bounds on a variety of deformation measures (such as inelastic work dissipated within any portion of the body, inelastic strains and displacements), some of which are new results, others recover or generalize known results. The resulting bounding technique possesses a quite unified character which is useful for computational purposes. The concept of “pseudo-plastic” strain is shown to be crucial for the derivation of bounds applicable above the shakedown limit.     

浅议影响核素迁移的几种地下水化学反应

放射性核素在地质介质中的迁移，除了受到地下水的对流-弥散作用外，还受到地下水中多种化学作用的影响，本文从影响核素迁移的角度出发，对几种主要的水化学作用进行了简要的论述，指出了目前存在的问题。     

Uncertainty and sensitivity analyses of the Kozloduy pump trip test using coupled thermal–hydraulic 3D kinetics code

The modeling of complex transients in nuclear power plants (NPP) remains a challenging topic for best estimate three-dimensional coupled code computational tools. This technique is, nowadays, extensively used since it allows decreasing conservatism in the calculation models and performs more realistic simulation and more precise consideration of multidimensional effects under complex transients in NPPs. Therefore, large international activities are in progress aiming to assess the capabilities of coupled codes and the new frontiers for the nuclear technology that could be opened by this technique. In the current paper, a contribution to the assessment and validation of coupled code technique through the Kozloduy VVER100 pump trip test is performed. For this purpose, the coupled RELAP5/3.3-PARCS/2.6 code is used. The code results were assessed against experimental data. Deviations between code predictions and measurements are mainly due to the used models for evaluating and modeling of the Doppler feedback effect. Further investigations through the use of two “antagonist” uncertainty GRS and the CIAU methods, were considered in order to evaluate and quantify the origin of the observed discrepancies. It was revealed on one hand that relative error quantification discrepancies exist between the two approaches, and further enhancements for both methods are needed.     

The calculation of stress intensity factors using special three-dimensional elements

A new, special three-dimensional finite element has been developed to investigate general fracture mechanics problems. Excellent correspondence between the results calculated utilizing the new element and other computational techniques was obtained for a three-dimensional compact fracture specimen analysis. The model is composed of special elements around the crack front and quadratic, isoparametric elements elsewhere. A considerable amount of fundamental information was also revealed from this analysis. This information is, of course, important to interpretation of fracture test results which are typically obtained from this type of specimen geometry. Shape functions for this special element are given explicitly. The shape functions provide the constant strain and rigid body motion capabilities and conformability with quadratic isoparametric elements.