多层油藏产量劈分新方法及应用

综合考虑不同含水饱和度下油水流动能力的不同和常规的黏度、地层系数、压力等参数对多层合采油藏产量劈分的影响,并且根据生产动态数据,应用多元线性拟合的方法,计算油水相对渗透率,提出新的动态分析相渗产量劈分法.新方法不仅考虑了黏度、地层系数等因素,最重要的是结合了以动态数据多元线性拟合为基础的相渗曲线.将实例的数值模拟计算结果和常规地层系数法劈分结果进行对比发现,应用该方法进行产量劈分的结果精确度高,适用性强.     

Combined damaged elasticity and creep modeling of ceramics with wedge splitting tests

During the crack propagation in common refractory ceramics at high temperatures, creep may occur in the wake of a process zone and in front of a crack tip. To account for this phenomenon, an integrated material constitutive model was developed by combining the mechanical behavior following isotropic damaged elasticity concept and Norton-Bailey creep. The post peak fracture behavior followed the bilinear softening law and a simple criterion was defined to consider the creep asymmetricity in uniaxial tension and compression. The material constitutive model was applied to inversely identify mode I fracture parameters with wedge splitting tests of an alumina spinel material at 1200 °C. It showed that the mean ratio of the nominal notch tensile strength to the actual tensile strength was 1.93 and the mean pure fracture energy was 297.6 N/m. In addition, the creep contributed 12.9% on average into the total fracture energy.     

On the calibration of cohesive parameters for refractories from notch opening displacements in wedge splitting tests

Cohesive elements are commonly used to describe crack propagation in heterogeneous materials with toughening mechanisms. This work aims to provide a guideline on how these fracture parameters can be calibrated using notch opening displacements (NODs) measured via digital image correlation and force data from wedge splitting tests (WSTs). Weighted finite element model updating was applied to calibrate material and boundary condition parameters in the same framework. The influence of each parameter on force and NOD data are given together with uncertainties for the calibrated parameters. Numerical results were in very good agreement in terms of splitting force, NOD, displacement and gray level residual fields. It is shown that images obtained during WSTs focusing on the crack path (i.e., hiding the loading region) can be used to drive numerical simulations and obtain cohesive parameters.     

建立劈分法轧制H型钢异型坯的宽展模型

介绍了劈分法轧制H型钢异型坯的特殊孔型系统及工艺,在充分考虑孔型形状和轧辊压下对宽展的影响的基础上,把腿部宽展和腰部宽展分开来计算,并且针对不同孔型和不同道次给出了相应的宽展计算公式,理论计算与现场数据相符合.     

Pro/E分模中斜顶的快速解决方案

Pro/E在模具制造行业中应用较广，主要取决于它在模具制造中的解决方案，Pro／E在实体与曲面（特别实体功能）及分模方面有它独特的一面，基于作者多年的的实践工作体会，现简单介绍快速处理斜顸的快速解决方案。     

两线切分轧制钢筋头部不齐问题的解决

针对安钢260机组小规格棒材实施两线切分轧制后，两线轧件在冷床上头部不易对齐问题进行了分析，认为其产生原因是切分后的2根轧件存在尺寸差，为此提出了具体的改进措施和调整办法。改进后，定尺率、成材率均提高0．5％以上。     

大规格轴承钢GCr15剪切撕裂情况的探讨

针对大规格轴承钢轧材在剪切过程中出现的撕裂现象进行了探讨,现场及取样分析结果表明:剪刃间隙过大、剪刃经磨损变钝是造成剪切撕裂的直接原因。另外,轧材内部存在缺陷也能促进剪切撕裂的形成。     

A finite volume–finite difference method with a stiff ordinary differential equation solver for advection–diffusion–reaction equation

A model for atmospheric pollutant transport is proposed considering an advection–diffusion–reaction equation. A splitting method is used to decouple the advection, diffusion and reaction parts. A scheme based on finite volume, finite difference and backward differentiation formula is used for solving an atmospheric transport-chemistry problem.     

半球谐振陀螺仪频率裂解及固有刚性轴的测试方法

半球谐振陀螺仪以其寿命长、可靠性高、体积小、重量轻、精度高而且可微型化的优点将在卫星、潜艇等导航领域有着广泛的应用前景。对半球谐振陀螺仪的而言,频率裂解值与固有刚性轴的位置是其关键的技术指标,因此设计测试方案对其进行精确测试是十分必要的。根据陀螺仪工作原理,从理论角度进行了推导,建立存在频率裂解及与固有刚性轴不重合时谐振子的运动方程,通过研究主驻波及辅助波的表达式,进而得到了振动位移的精确表达式,最后设计了在固定位置安装两组激励电极以及两组位移传感器对频率裂解以及固有刚性轴位置进行测试的测试方案,并给出了最佳的测试时间。     

Fast local image inpainting based on the Allen–Cahn model

In this paper, we propose a fast local image inpainting algorithm based on the Allen–Cahn model. The proposed algorithm is applied only on the inpainting domain and has two features. The first feature is that the pixel values in the inpainting domain are obtained by curvature-driven diffusions and utilizing the image information from the outside of the inpainting region. The second feature is that the pixel values outside of the inpainting region are the same as those in the original input image since we do not compute the outside of the inpainting region. Thus the proposed method is computationally efficient. We split the governing equation into one linear equation and one nonlinear equation by using an operator splitting technique. The linear equation is discretized by using a fully implicit scheme and the nonlinear equation is solved analytically. We prove the unconditional stability of the proposed scheme. To demonstrate the robustness and accuracy of the proposed method, various numerical results on real and synthetic images are presented.