Design and optimization of W/Cu divertor mock-ups

Tungsten is a promising candidate for plasma-facing materials to cover the surface of the divertor plate in the design of an international thermonuclear experimental reactor （ITER）. Copper as a heat sink material serves to transfer heat excellently. Divertor mock-ups with W/Cu graded interlayers were designed to reduce thermal stresses. Thermally induced stresses and temperature in a W/Cu divertor mock-up were analyzed using the finite element method. The graded structures with different exponents p and thick- nesses were designed and discussed. The conclusions drawn from these analyses are that thermal stresses reach the minimum and the temperature is suitable when exponent p is 1.5 and the thickness of five graded interlayers is 5 mm.

Preliminary High Heat Flux Tests of Small-Scale Be/Cu Mock-Ups

China, as one of the members of ITER （international thermonuclear experimental reactor） project, one of the most important construction tasks is the fabrication of the first wall panel and shield blankets, which is the key engineering technology of ITER construction and might be one of the crucial issues of the future reactor too. Since 2004, an associated research team including Southwestern Institute of Physics （ SWIP ）, Ninxia Non-ferrous Metal Co. Itd and Chinese Institute of Engineering Physics, as well as Nuclear Power Institute of China has been established. Up to now, several series of interlayer for hot isostatic press （ HIP ） connection of beryllium and CuCrZr alloy have been tested. They are titanium film or coating, Cu coating and Al or AISiMg alloy etc. The bonding strength （tensile or shear strength ） of HIPed Be/Cu joints is up to 100 MPa.

Design and validation of the THMC China-Mock-Up test on buffer material for HLW disposal

According to the preliminary concept of the high-level radioactive waste （HLW） repository in China, a large-scale mock-up facility, named China-Mock-Up was constructed in the laboratory of Beijing Research Institute of Uranium Geology （BRIUG）. A heater, which simulates a container of radioactive waste, is placed inside the compacted Gaomiaozi （GMZ）-Na-bentonite blocks and pellets. Water inflow through the barrier from its outer surface is used to simulate the intake of groundwater. The numbers of water injection pipes, injection pressure and the insulation layer were determined based on the nu- merical modeling simulations. The current experimental data of the facility are herein analyzed. The experiment is intended to evaluate the thermo-hydro-mechano-chemical （THMC） processes occurring in the compacted bentonite-buffer during the early stage of HLW disposal and to provide a reliable database for numerical modeling and further investigation of engineered barrier system （EBS）, and the design of HLW repository.

Digital Mock-up Technology in Product Development and Research

After introducing the present status of digital mock-up (DMU) technology in product development and research,the modeling and its key technologies in product design are described. The architecture of digital design platform system for main DMU model is developed. Based on the architecture,a method of skeleton design has been applied to the development of digital design system.

Effects of synthetic site water on bentonite-concrete system for a potential nuclear waste repository

In high-level nuclear waste(HLW)repositories,concrete and compacted bentonite are designed to be employed as buffer materials,which may raise a problem of interactions between concrete and bentonite.These interactions would lead to mineralogy transformation and buffer performance decay of bentonite under the near field environment conditions in a repository.A small-scale experimental setup was established to simulate the concrete-bentonite-site water interaction system from a potential nuclear waste repository in China.Three types of mortars were prepared to correspond to the concrete at different degradation states.The results permit the determination of the following:(1)The macroproperties of Gaomiaozi(GMZ)bentonite(e.g.swelling pressure,permeability,the final dry density,and water content of reacted samples);(2)The composition evolution of fluids from the synthetic site water-concrete-bentonite interaction systems;(3)The sample characterization including Fourier transform infrared spectroscopy(FTIR)and X-ray powder diffraction(XRD).Under the infiltration of the synthesis Beishan site water(BSW),the swelling pressure of bentonite decreases slowly with time after reaching its second swelling peak.The flux decreases with time during the infiltrations,and it tends to be stable after more than 120 d.Due to the cation exchange reactions in the BSW-concrete-bentonite systems,the divalent cations(Ca and Mg)were consumed,and the monovalent cations(Na and K)were released.The dissolution of minerals in the bentonite such as albite causes Si increasing in the pore water.It was concluded that the hydro-mechanical property degradation of bentonite takes place when it comes into contact with concrete mortar,even under low-pH groundwater conditions.The soil dispersion,the uneven water content,and the uneven dry density in bentonite samples may partly contribute to the swelling decay of bentonite.Therefore,the direct contact with concrete has an obvious effect on the performance of bentonite.

多领域功能样机可交换模型规范实现研究

针对不同领域仿真工具模型的重用互换需求,欧洲仿真界提出了功能样机可交换接口规范Functional Mock-up Interface for Model Exchange(FMI)。基于FMI接口规范,详细分析了功能样机可交换模型的结构与功能,研究了规范对仿真模型变量、方程和仿真算法的描述,并在多领域物理系统建模仿真平台MWorks中设计了FMI接口,实现了MWorks模型的重用,扩展了MWorks模型的使用范围。目前,MWorks是国内唯一支持该规范的建模仿真工具。

钛管子管板自动钨极氩弧焊工艺

通过钛管子管板焊接性分析、焊接保护、焊接规范参数合理的分析,通过Mock-up模拟试验,制定合理的自动钨极氩弧焊接工艺参数及焊接坡口形式,管子管板焊接试样经无损检测、宏观试验、微观试验、硬度检验证明其焊接质量合格,并在产品上应用推广。

Manufacturing and High Heat Flux Testing of Brazed Flat-Type W/CuCrZr Plasma Facing Components

Water-cooled flat-type W/Cu Cr Zr plasma facing components with an interlayer of oxygen-free copper（OFC） have been developed by using vacuum brazing route.The OFC layer for the accommodation of thermal stresses was cast onto the surface of W at a temperature range of 1150oC-1200 oC in a vacuum furnace.The W/OFC cast tiles were vacuum brazed to a Cu Cr Zr heat sink at 940 oC using the silver-free filler material Cu Mn Si Cr.The microstructure,bonding strength,and high heat flux properties of the brazed W/Cu Cr Zr joint samples were investigated.The W/Cu joint exhibits an average tensile strength of 134 MPa,which is about the same strength as pure annealed copper.High heat flux tests were performed in the electron beam facility EMS-60.Experimental results indicated that the brazed W/Cu Cr Zr mock-up experienced screening tests of up to 15 MW/m^2 and cyclic tests of 9 MW/m^2 for 1000 cycles without visible damage.

N06022镍基合金半管夹套的焊接

本文阐述了N06022镍基合金的焊接特性,分析了不开坡口角焊缝,开内坡口全焊透角焊缝、开外坡口全焊透角焊缝的优缺点以及介绍了半管最小间距的要求。产品半管焊接前,对焊工进行了GTAW焊接方法的MOCK-UP试验,对MOCK-UP焊接试板进行无损检测、宏观试验、微观试验、角焊缝有效厚度检测、角焊缝弯曲试验,各试验项目合格。经MOCK-UP试验考试合格的焊工对产品进行焊接,保证了N06022镍基合金半管的产品质量。

Thermal Fatigue Study on the Divertor Plate Materials

Thermal fatigue property of the divertor plate is one of the key issues that governs the lifetime of the divertor plate. Taking tungsten as surface material, a small-mock-up divertor plate was made by hot isostatic press welding (HIP). A thermal cycling experiment for divertor mock-up was carried out in the vacuum, where a high-heat-flux electronic gun was used as the thermal source. A cyclic heat flux of 9 MW/m2 was loaded onto the mock-up, a heating duration of 20 s was selected, the cooling water flow rate was 80 ml/s. After 1000 cycles, the surface and the W/Cu joint of the mock-up did not show any damage. The SEM was used to analyze the microstructure of the welding joint, where no cracks were found also.

Application of Assembly Modeling and Simulation Technology to a Large Size Wind-drive Generator

Challenges still remain in carrying out assembly modeling efficiently in virtual assembly （VA） fields. One of the root causes is the apparent weakness in effective description of assembly knowledge and information. The assembly modeling, disassembly modeling, assembly interference inspection, assembly sequence planning and optimization, and assembly simulation display for key techniques is studied theoretically in this paper. An example of product assembly modeling is provided to illustrate the effectiveness of the proposed approach. On the basis of re- search, using assembly simulation techniques and multimedia techniques to finish structure design in linkage design of a large size wind-drive generator. The application of the modeling method has shortened the lead time dramatically.

A Simulation Study on the Thermal Shock Behavior of Tungsten Mock-Up under Steady-State Heat Loads

In a fusion reactor,due to high heat flux（HHF） loads,the plasma facing components（PFCs） will suffer severe thermal shock.In this paper,the temperature distribution and thermal-stress field of tungsten armor under HHF loads were investigated by the method of finite element modeling and simulating.The orthogonal experiment and range analysis were employed to compare the influence degree of four representative factors：steady-state heat flux;thickness of tungsten armor;inner diameter of cooling tube and the coefficient of convection heat transfer（CCHF） of cooling water,on thermal shock behavior tungsten mock-ups,and then get an optimization model to conduct the transient heat flux experiment.The final simulation results indicated that the steady-state heat flux and the thickness of W armor are the main influential factors for the maximum temperature of mock-ups.Furthermore,the influence of transient thermal shock all mainly concentrates on the shallow surface layer of tungsten（about 500 μm） under different transient heat flux（duration 0.5 ms）.The results are useful for the structural design and the optimization of tungsten based plasma facing materials for the demonstration reactor（DEMO） or other future reactors.