Thermal Buckling of Imperfect Deep Functionally Graded Spherical Shell

Thermal buckling analysis of deep imperfect functionally graded (FGM) spherical shell is considered in this paper. A mixture of ceramic and metal is considered for the FGM shell and the material properties, such as the modulus of elasticity and coefficient of thermal expansion, vary by a power law function through the thickness. Employing the Sanders non-linear kinematic relations, total potential energy function is derived and the equilibrium and stability equations are obtained for the imperfect shell. Approximate solutions satisfying the simply supported boundary condition are assumed and using the Galerkin method the error due to the approximation is minimized. The geometrically imperfect shell is considered and three types of thermal loadings, such as the uniform temperature rise (UTR), linear temperature rise through the thickness (LTR), and non-linear temperature rise through the thickness (NLTR) are considered and their associated buckling temperatures are obtained. The effects of different temperature functions and the magnitude of initial geometric imperfection are examined on the thermal buckling loads of the shell.     

槽控机故障自检与处理

铝电解槽微机控制系统应用越来越广泛。充分挖掘微机控制系统的潜力,完善故障自动检测,特别是关键回路自检,使故障得到及时处理,是控制系统改造中的重要内容。本文就铝电解槽自动控制机的改造、交流口电路设计,以及故障自检与处理方面进行了探讨。     

多孔并联分段低压输水系统的水力特性和控制

在详细分析多孔并联分段低压输水系统水力特性的基础上，建立了这一输水系统的非恒定流控制方程以及关闸和不关闸条件下的保水堰边界条件。应用所建立的数学模型对南水北调天津干线工程进行了数值模拟计算，得到了运行工况和检修工况下该输水系统的水力特性以及并联空间连通性对水力特性的影响，并提出相应的控制措施。本文还针对输水系统的水力特性，对单联分段低压输水单元的水力振荡方程进行了修正，推导出多孔并联分段输水单元的水流振荡方程和连通式保水堰自由水面的固有振荡频率公式，提出了消除水力共振、缓解输水单元水力振荡的控制条件，为工程设计和运行管理提供技术依据。     

沉淀池数值模拟技术的研究进展与评论

在水处理应用当中的沉淀池数值模拟研究近些年取得了很大的进展.自20世纪70年代,国外的研究人员开始进行许多沉淀池场方面的试验研究与数值模拟工作,在试验测量方面进行了原型池与模型池的测量,包括对速度场与浓度场都进行了许多的测量工作.国内于近几年也开始开展一些数值模拟研究工作,但试验测量方面的工作几乎没有.数值模拟技术尚未能很好地发展到实际工程应用的阶段.对模型的最新进展、所需解决的关键性问题进行了总结.     

Pressure Behavior for Spherical Flow in a Reservoir of Non-Newtonian Power-Law Fluids

The pressure variations during polymer flooding of oil reservoirs for oil recovery projects can be used to analyze the flow in the reservoir which is especially useful for the partially perforated reservoirs. This paper presents a relationship between the viscosity and the shear rate which is similar to forms developed for radial flow (Odeh, A. S., Yang, H. T. ([1979]). SPEJ. AIME (Jun.) 155). The power-law viscosity model is used to give the variation of the fluid viscosity with the spherical radius for a mathematical model of unsteady spherical flow for non-Newtonian fluids with wellbore storage and skin. An analytical solution for the wellbore pressure responses derived in Laplace space is used to analyze the behavior characteristics at early and later times to interpret the well-test parameters. The pressure variations are similar to those for a Newtonian fluid at the early times, but at later times, the variation of the viscosity with the power-law exponent is important, so the pressure response differs from that for a Newtonian fluid. The solution has significance for interpreting well test parameters for non-Newtonian spherical flow.     

成品油储罐内的腐蚀及防护

对成品油储罐内各部位腐蚀情况进行了介绍，说明了产生腐蚀的原因和腐蚀机理。介绍了油罐内防护技术，采用节点加固，降低边缘应力，可减缓油罐金属腐蚀速度；对选用油罐内防腐涂料的原则进行了阐述。     

球罐组装工艺的选择及施工技术关键

经过多年的技术改进和创新,已形成与我国施工企业技术和设备条件相适应的三种球罐组装工艺,即分带组装法、分片组装法和混合组装法。本文在分析各种方法工艺特点的基础上,从球罐的数量、规格、结构、施工现场条件和施工企业状况等方面,介绍球罐组装工艺的选择及施工技术关键。     

中国球形容器建设回顾与展望(续3)

系统介绍中国工业用球形容器自１９５８年开始建造迄今４０年来的历史,综述中国球形容器建造技术水平发展概况,展示达到世界先进技术水平的成果,分析与世界先进技术水平的差距,展望２１世纪中国球形容器建造技术的发展前景。     

低温乙烯球罐局部缺陷的修复

针对低温乙烯球罐局部超标缺陷返修中出现的情况,从材料、结构、焊接工艺等方面进行分析探 讨,提出在WES3003LT490钢制低温球罐局部返修过程中值得借鉴的问题。     

金属油罐的渗漏与修复

分析了金属油罐渗漏的部位及原因，根据实际情况采取不同的方法进行修复。