17辊六重式中板矫直机技术分析

以一台高精度六重式铝板矫直机为例,对矫直厚度较大的铝板矫直机进行了完整的技术分析,包括六重式辊系布置特性、矫直主要力能参数、矫直机结构分析。     

中厚板表面“黑点麻坑”的形成机理研究

针对南钢中厚板表面麻坑缺陷较严重的问题,结合实际生产工艺研究了该缺陷的形成机理.结果表明,该缺陷是热轧时形成的氧化皮破碎后压入钢板表面造成的,形成于精轧后部道次.通过优化实际生产中的热轧和除鳞工艺,有效提高了产品表面质量,降低了生产成本.     

Li-Mn-Ti复合氧化物的结构及其在酸介质中的稳定性

采用固相法合成系列Li-Mn-Ti复合氧化物(理论化学式为LiTi<,x>Mn<,2-x>p<,4>,0≤x≤1);利用热重-差示扫描量热法(TG-DSC)、X射线衍射(XRD)和扫描电子显微镜(SEM)等对其结构和形貌进行表征,并通过酸浸实验考察其在弱酸性介质中的稳定性.结果表明:当x≤0.5时,Ti能完全地纳入尖晶石晶格,并使晶胞参数增大、晶粒变小;Li-Mn-Ti复合氧化物酸浸前、后能够保持尖晶石的结构和形貌,具有结构稳定性,但其化学稳定性还有待进一步提高.     

钒钛微合金化对铸态中锰钢组织和性能的影响

通过试验研究,探讨添加钒钛微合金化对铸态中锰钢的组织性能的影响,确定钒钛微合金的合适加入量,实验表明经添加V质量分数为0．1％。0．2％或Ti0．15％与稀土和硅钙合金的复合处理后的铸态中锰钢,在中低冲击载荷下耐磨性能优于高锰钢,实现铸态中锰钢在中低冲击载荷下使用具有良好的耐磨性,该项目的研究具有良好的经济与社会效益。     

智能干油集中润滑系统在中厚板矫直机设计中的应用

以中厚板矫直机为例,对智能干油集中润滑技术在矫直机工作辊轴承以及设备其余相对滑动面的润滑应用进行了完整的技术方案介绍,包括智能润滑原理、润滑特点、润滑设备的规格,并与传统干油润滑方式进行了比较。     

磁场作用下轮轨黏着特性研究

利用JD-1轮轨模拟试验机研究水和油介质工况下磁场对轮轨黏着特性的影响。结果表明:在水和油介质工况下,磁场作用下的轮轨黏着力大于无磁场作用的黏着力,其中加磁水介质黏着力相对增幅达20%,加磁油介质黏着力相对增幅达50%;水和油介质工况下,施加磁场时速度对轮轨黏着力影响不大。     

The method of fundamental solutions for solving free boundary saturated seepage problem

The problem of seepage flow through a dam is free boundary problem that is more conveniently solved by a meshless method than a mesh-based method such as finite element method (FEM) and finite difference method (FDM). This paper presents method of fundamental solutions, which is one kind of meshless methods, to solve a dam problem using the fundamental solution to the Laplace's equation. Solutions on free boundary are determined by iteration and cubic spline interpolation. The numerical solutions then are compared with the boundary element method (BEM), FDM and FEM to display the performance of present method.     

具有复合介质的感应炉的电参数计算

对具有复合介质的感应电炉的电磁场理论进行了研究，导出工程实用的电参数计算公式，计算分析目前常用的两种典型复合介质熔炼炉的电参数，其结果更符合复合介质感应熔炉的实际。     

井下换热器周围对流型地热储传热特性

采用Darcy自然对流传换模型分析了同轴管式井下换热器（DCHE）在对流型地热储中的换热物性，在假设井下换热器外壁温度变化与其高度成幂函数关系的基础上，建立了数学模型并得出了相似妥，为其进一步工程应用奠定了较好的理论基础。     

Transient free convective flow through a vertical cylinder filled with a porous material

This article aims to explore the impressive impact of emerging parameters on transient fully evolved free convective flow inside a vertical cylinder containing a porous material. The mathematical formulation of the model related to the considered physical circumstance is presented under compatible boundary conditions. Closed‐form solutions are received for the velocity field, the temperature distribution, mass flux, skin friction, and the Nusselt number in terms of Bessel functions and modified Bessel functions of the first kind. Impressive effects of parameters such as the Darcy number $Da$, Prandtl number $\text{Pr}$, viscosity ratio $M$, and also time $t$ on both the velocity and temperature distribution have been explored employing graphs and tables. It is irradiated by analysis that flow erection, heat transfer rate, skin friction, and mass flux are admirably impacted by the Prandtl number, the Darcy number, viscosity ratio parameter, and time. It is found that both the velocity and temperature field profiles rise with the rising value of time and ultimately attain their steady state. Moreover, the Prandtl number and the viscosity ratio parameter reduce the velocity profiles, while the reverse phenomenon occurs with the Darcy number.