60000m~3/h空分设备物料平衡及变负荷控制原理

文章以60000m3/h空分设备为例,以理论计算为基础,从物料平衡角度出发,介绍空分设备的自动变负荷的控制原理和计算。实际运行证明,自动变负荷控制系统运行效果较好。     

Nonlocalized Fatigue Damage of Metals and Alloys. Part 2. Interrelation between Fatigue and Inelasticity

The paper considers interrelation between the regularities in the fatigue fracture and inelastic deformation taking into account the material properties, stress gradient and concentration, specimen size, load cycle asymmetry, complex stress state, temperature, loading frequency and conditions, scatter of the test results. Analysis of the data from the literature and results of original investigations has shown that the characteristics of inelasticity, which define nonlocalized fatigue damage, can be used in studies of general regularities of the high-cycle fatigue fracture. Specific results of such analysis are presented. __________ Translated from Problemy Prochnosti, No. 5, pp. 5 – 29, September – October, 2005.     

Analysis and Reduction of Ultrasonic Pitting Defects on Hard Disk Surfaces

It has become of paramount importance to be able to perform failure analysis of defects on hard disk surfaces quickly and accurately. In this study, ultrasonic pitting defects on hard disk surfaces were investigated. A new electrical tagging pattern system, which directly translated the channel bits to magnetic transitions during writing of the magnetic pattern around a defect, was used in the failure analysis of magnetic recording disks to mark defective sectors. With the help of the Kerr magneto-effect, the defective sectors were effectively located for further failure analysis. Results of the failure analysis revealed that there was 30% to 40% loss of the recorded magnetic bit signal due to an increase in the gap between a recording head and a hard disk surface with ultrasonic pitting defects. The experiments performed indicated that low ultrasonic power for disk cleaning could reduce the ultrasonic pitting defects significantly. The maximum failure rate due to single-type ultrasonic pitting defects was reduced from 33.4% to 16.7%, while the maximum failure rate due to cluster-type ultrasonic pitting defects was reduced from 11.1% to 5%.     

Modeling and testing of energy absorbing lightweight materials and structures for automotive applications

As a consequence of the increasing demands in automotive industry concerning crashworthiness and passive safety, the concern for energy management and safety demands also increases. The goal of energy management is to reduce the forces and stresses on an occupant or a pedestrian during a crash event; in some cases it may be possible to reduce the forces by a factor of two. This requires usage of new advanced materials in automotive components. Energy absorbing foams and other lightweight materials like plastics and polymer composites are increasingly used in automotive industry. Hence, extensive study of energy absorbing behavior of these materials as well as the automotive components is needed for further improvements in numerical modeling and crash simulations. The paper enlightens recent advances in investigation of mechanical properties and energy absorption ability of the mentioned lightweight materials as well as modeling with finite element codes for crash simulations.     

锆合金的碘致应力腐蚀开裂研究(英文)

研究了不同热处理状态的Zr-2和Zr-4合金在不同浓度的碘介质及实验温度下的应力腐蚀开裂(SCC)行为。并对不同织构取向的试样在350℃下进行了蠕变实验,蠕变实验的载荷值选择与SCC实验相对应的一系列典型载荷。用扫描电子显微镜观察了断口特征,用透射电子显微镜和光学显微镜检查了材料的显微组织,用X-光衍射仪测定了锆合金的织构,分析讨论了材料状态、实验温度、碘浓度以及蠕变对锆合金碘致应力腐蚀行为的影响。     

Ultimate load carrying capacity of the Lu Pu steel arch bridge under static wind loads

This paper investigates the ultimate load carrying capacity of the Lu Pu Bridge under static wind loads through the spatial finite element model. Both geometric and material nonlinearities are involved in the analysis. The Lu Pu Bridge is a long-span half-through-type steel arch bridge with a 550 m-long central span under construction in Shanghai, China. This will be the longest central span of any arch bridge in the world. Three load combinations are used in the ultimate load capacity analysis of the bridge. Combination I: combined dead and live loads over the entire bridge. Combination II: combined dead and wind loads. Combination III: combined dead load, wind load and live load over the entire bridge. Ultimate load capacity of the bridge is first investigated under load combinations I and II. Attention is paid mainly to investigate the load capacity of the bridge under load combination III. In the case of load combination III, the influences of several parameters (i.e., loading sequence, three components of wind loads and wind loads of individual bridge element) on the ultimate load capacity of the bridge are discussed. It is concluded that wind loads result in significant reduction in the ultimate load capacity when applied wind loads become large.     

Computer-aided design method for the components made of heterogeneous materials

With rapid developments of high-tech in various fields, there appear more critical requirements for special functions of components/products, which can be satisfied only by using heterogeneous materials: composite materials, functionally graded materials, or heterogeneous materials with a periodic microstructure. However, currently there exists no systematic and effective method for designing components made of these heterogeneous materials. This paper develops such a computer-aided design method, under the guide of Axiomatic Design, which can apply the functions of current CAD/CAE software. With the design method, all the information about both configuration and materials of a heterogeneous component, needed for creating its CAD model, can be obtained.     

分布式物料管理系统的开发

本文将分布式体系结构应用于某企业的物料管理系统中，对本系统的需求做了一定的分析，介绍了应用系统的结构、开发方法与实现，解决了该公司的实际问题，实现了对企业物料的入库、出库、维修、公司合同，付款等功能的管理，对国内现有企业的物料管理具有现实的指导意义。     

针织企业物资供应网络管理与决策支持研究

该文基于针织企业对物资供应的网络管理与决策支持进行了研究，首先对计算机管理进行了可行性分析，设计了系统总体方案，然后提出了了系统实现的难点及系统开发环境和工具；最后，对“物资采购计划”建立了数学模型，设计了辅助决策支持系统。     

OPGW光缆热性能的研究

提出了分析计算光纤复合架空地线(OpticalFiberCompositeOverheadGroundWires,OPGW)热性能的改进综合法,它利用分布函数求解趋肤效应并采用数值计算方法求解初始状态,在短路电流冲击的全过程中求解热交换性能,具有精度高、效果好等特点。利用该方法详细分析了几种常用OPGW的结构、材料与热性能之间的关系,结果表明光缆热性能分析对于OPGW产品的选型及运行维护具有重要的指导意义。