A fast integral approach for drag force calculation due to oscillatory slip stokes flows

In this paper, we describe an efficient numerical method for modelling oscillatory incompressible slip Stokes flows in three dimensions. The efficiency is achieved by employing an integral approach combined with an accelerated boundary‐element‐method (BEM) solver. First the integral representations for slip flows with two different slip models are formulated. The resulting integral equations are then solved using the BEM combined with the precorrected‐FFT accelerated technique. 3D numerical codes have been developed based on the method described above. These codes are then used to calculate the drag forces on oscillating objects immersed in an unbounded slip flow. Three objects are considered, namely a sphere, a pair of plates and a comb structure. The simulated drag forces on these objects obtained from the two slip models are compared. In the sphere case, the simulated results are also compared with the analytical solutions for both the steady‐state case and the no‐slip oscillatory case and are found to be in good agreement. In addition, qualitative comparison of the simulation results with the experimental results in the plate problem is also presented in this paper. Copyright © 2004 John Wiley & Sons, Ltd.     

Approximate analytic solutions of adiabatic capillary tube

Approximate analytic solution of capillary tube is valuable for theoretical analysis and engineering calculation. In this work, two kinds of approximate analytic solutions of adiabatic capillary tube have been developed. One is the explicit function of capillary tube length. Another is the explicit function of refrigerant mass flow rate. In these solutions, the choked flow condition is taken into account without iterative calculations. The approximate predictions are found to agree reasonably well with experimental data in open literatures.     

不锈钢母液的凝固点及流动性的实验研究

对不同含铬量的铁水凝固点和流动性进行了实验测定。结果表明，含铬铁水的凝固点和流动性与普通铁水完全不同，含铬铁水碳饱和时，铁水温度及含铬量是影响其凝固和流动性的主要因素，通过热力学分析解释了碳化物析出影响铁水流动性的原因。     

弱爆炸波吹灰器在贵溪电厂4号机组的应用

弱爆炸波吹灰技术是近几年发展起来的锅炉尾部受热面的除灰方法，它能长期稳定可靠的运行。是一种高效节能免维护的新型专利产品。介绍了弱爆炸波除灰技术的基本原理及程控步骤在DCS系统中的实现。     

涡轴发动机最优加速控制研究

研究了航空涡轴发动机加速过程的最优控制问题。采用的优化方法是序列二次规划法(SQP)。研究表明，将序列二次规划法应用于涡轴发动机最优加速控制是可行的，加速过程的寻优控制规律正确。在8项约束的范围内以及在保证发动机安全的前提下，与传统的PID控制结果相比，改善了发动机的动态性能，达到进一步发挥发动机性能潜力的目的。     

用CAXA三维电子图板V2实现机座的造型和出图

研究利用CAXA三维电子图板V2绘图软件进行减速器机座的实体造型和工程图输出，找出绘图软件在机械设计应用中存在的不足，指出软件设计尚待解决的剖视图处理缺陷。以及二、三维图形相脱节等问题。     

三相交流输电线路的电磁环境(一)

本文定量分析计算三相交流输电线路正常运行工频电、磁场对周围环境影响,以及产生电晕时对无线电接收的干扰影响。并分析在输电线路短路状态下其电磁场对周围环境的影响。     

Properties of Magnetic Nanoparticles about Doped Rare Earth and Its Composites

The magnetic liquid was prepared with ferric salt by inorganic gel technology. The effect of the doped rare earth elements on the properties of magnetic particles was analyzed. The magnetic liquid was composed with clay mineral into magnetic mineral composites. The crystal structure and micro-morphology of the nanoparticles were studied by XRD and TEM. The results show that the crystal structure of the magnetic particles doped 0.5 % of lanthanum is more complete, and the magnetic response capability is higher with doping agent. At the same time, the possibility of the clay mineral magnetic composites as the carrier of target drug was probed.     

一种基于VirtualClock的自适应成比例带宽分配算法

该文提出了一种基于VirtualClock算法的自适应成比例带宽分配算法(ProportionalAdaptiveBandwidthAllo-cationAlgorithmBasedonVirtualClock,PABVC)。该算法将所有的业务流分为绑定流和非绑定流,并根据不同流的配置加以调度,从而实现了绑定带宽同时自适应成比例分配带宽的目的。由于算法的各个部分相关性较弱,所以在保留算法框架和核心部分算法的基础上,可以灵活地加以组合,实现不同的算法变种。最后,该文分析了PABVC算法的优缺点,并且提出了今后的研究重点。     

声表面波力敏传感器的研究

本文分析了声表面波（ｓｕｒｆａｃｅａｃｏｕｓｔｉｃｗａｖｅ简称ＳＡＷ）力敏传感器加载后，频率稳定性变差的原因。在此基础上，设计了一种新型的采用等应力加载的力敏传感器，计算了该传感器的灵敏度，并给出了该传感器的频漂实验和力—频特性实验结果，为传感器的实际应用打下了基础。