哈得4联合站技术改造

位于塔克拉玛干大沙漠腹地的哈得4油田,2004年成为全国最大的沙漠油田,2005年产量达到200×104t。在对联合站存在问题逐一分析的基础上,提出了技术改造的措施。现场采集的运行数据表明技术改造效果明显,增强了流程可靠性,提高了自动化水平,降低了能耗。     

自喷井电动清蜡绞车的研制

针对目前石油钻采用清蜡绞车总体结构设计不合理以及实用性不强等技术难题,研制开发了自喷井电动清蜡绞车。该绞车的核心部件包括过载保护安全装置、牙嵌离合器轴套、自动/手动互换装置、计量装置以及密封装置。在清蜡绞车自动工作中,当清蜡刮刀遇到较大阻力时,清蜡绞车将接收到反馈信号,可实现智能停车,自动转换为手动状态,以便操作人员检查和排除故障,从而确保了操作的安全性,延长了设备的使用寿命。1000余台电动清蜡绞车的现场应用表明,该产品可以大大降低原油的开采成本,具有良好的经济效益和社会效益。     

炼油厂成品油罐区调度优化问题研究

研究了以集合论为基础的调度优化模型。给出了该离散型优化问题的求解算法。根据优化结果，在G2实时智能平台上开发了包含监视子系统和调度子系统的调度支持系统。在中国石化股份有限公司长岭分公司的试用结果表明，该调度系统可以提高炼油厂的生产效率，从而提高炼油厂的经济效益。     

The influence of plastic properties on chip formation

A two-dimensional finite-element model of the chip formation process is used to study the influence of the material law determining plastic flow on chip formation of titanium alloys at high cutting speeds. For simplicity, friction and thermo-mechanical properties of the tool are neglected in the simulations. Titanium chips are strongly segmented and therefore especially suitable to study the role of segmentation for the cutting force and other cutting parameters. Of special interest is the influence of the thermal softening parameter in the material law. Increasing thermal softening leads to a drastic decrease in the cutting force and a corresponding increase in chip segmentation. A variation of the hardening exponent is also performed. It is shown that the simulation results can be understood by using adiabatic flow stress curves. The variation of the hardening exponent leads to strongly differing chip shapes, although the cutting force stays nearly constant. This shows that mean cutting forces should not be used as simulation verification parameters.     

NUMERICAL INVESTIGATION ON MUD BED-GENERATION AND IMPACTING A WALL ALONG A SLOPE

In this paper mud was treated as the Bingham fluid. In staggered grids, two-dimensional incompressible Navier-Stokes equations for non-Newtonian fluid was solved by the MAC method. Numerical simulations were conducted on mud bed-generating phenomenon and mud impacting a wall along a slope. The distributions of free surface, pressure and velocity of mud and water were obtained. The results indicate that the computed layer thickness of mud bed almost equals the theoretically predicted value. Because of the differences in constitutive relationship, the distributions of free surface are different for water and mud. The distortion of water free surface is much more complicated.     

利用黄河泥沙加固下游大堤

黄河是一条举世闻名的多泥沙河流，善淤、善决、善徒给沿河人民带来对过深重灾难，防洪问题一直是国家的心腹之患。泥沙问题是黄河防洪问题的症结所在。在总结固大堤经验的基础，进行挖河疏浚，淤筑“相对地下河”，已作为黄河治理的一项重大决策付诸实施。     

游梁式抽油机二次平衡分析

为解决游梁式抽油机能耗大、效率低的问题，设计了二次平衡装置。这种装置通过是挂在抽油机后端的平衡重的平衡作用，降低一次平衡曲柄轴净扭矩的两个峰值，达到减少能耗提高效率的目的。对抽油机的二次平衡作了较详尽的理论分析，给出了实行二次平衡后曲柄轴净扭矩的计算公式和安装二次平衡装置前后曲柄轴净扭矩曲线图。在大庆油田两口井上进行的现场试验结果表明，安装二次平衡装置后，两口井年节约电费分别为0.25万元和1．17万元，经济效益明显。     

超音速燃气射流非定常波系的数值研究

根据ＭＵＳＣＬ格式的基本思想，对格式进行了部分修改，数值模拟了超音速燃气射流流场的结构和发展过程。给出了流场谐波系的变化趋势，得到了流场达到稳定状态的时间和稳定后的流动图形。     

给水流量控制系统仿真辅助设计

本文将给水流量系统规范化，给出静、动态数学模型，通过计算机仿真计算建立起设计参数Ｓ与系统特性间关系数据库，这些数据可用于控制系统辅助设计。本文还介绍了在Ｓ较小时自动补偿系统增益和时间常数的自适应控制方法并给出仿真结果。     

A modified flow enforcement technique for ATM networks

In ATM networks the requirement of providing the negotiated Quality of Service (QOS) needs an efficient flow enforcement technique that will result in preventive congestion control. A very effective technique is the Exponentially Weighted Moving Average (EWMA) method. In this paper, we have suggested improvements to the EWMA and call it the Enhanced EWMA (EEWMA). Simulation results show that the EEWMA is consistently better than the EWMA in most of the situations. We present comparisons of cell loss under various conditions. No theoretical analysis is presented.