利用多孔介质计算机仿真模型研究粘性指进

为了研究多孔介质中粘性指进现象的发生和发展机理，基于随机理论建立了多孔介质计算机仿真模型。运用分形生长的理论在新建模型中进行粘性指进的模拟研究，分析了流体粘度差和非均质性对粘性指进的影响，讨论了驱替速度与粘性指进前缘分形维数之间的关系。分析结果表明，在多孔介质中，增加驱替流体粘度和降低驱替速度可控制粘性指进的发展。利用新建模型还可直观地观察到粘性指进产生的过程和剩余油的分布状态，实现了驱替过程的可视化。     

玉门油田细粉砂低温油藏防砂技术研究

为解决玉门油田细粉砂低温油藏防砂技术难题，研究了一种新的人工岩层防砂技术，分析了人工固结岩层防细粉砂的机理。对新型防砂材料的固结条件、固结温度、固结岩心的强度、渗透率和孔喉分布进行了室内试验研究，结果表明，防砂材料能在20℃的低温水环境中固结，固结岩心渗透率大于3μm^2，强度大于4MPa，岩心孔喉分布均匀，最小防砂粒径为4μm。现场应用表明，该防砂技术成功率高，可解决高泥质含量的低温细粉砂岩防砂技术难题。     

单压状态下混凝土的动力损伤本构模型

本文根据混凝土的损伤本构理论，结合混凝土在快速变形下的性能试验，在一定的假设下，导出了混凝土在快速变形下的损伤本构方程，并与试验结果进行了对比，两者吻合较好。     

Creep Modeling in Excavation Analysis of a High Rock Slope

Based on the distinct element method, a numerical procedure is presented for simulation of creep behavior of jointed rock slopes due to excavation unloading. The Kelvin model is used to simulate viscous deformation of joints. A numerical scheme is introduced to create incremental contact forces, which are equivalent to producing creep deformation of a rock-joint system. The corresponding displacement of discrete blocks due to creep deformation of contact joints can be calculated by equilibrium iteration. Comparisons of results between the numerical model and theoretical solutions of a benchmark example show that the presented model has excellent accuracy for analysis of creep deformation of rock-joint structures. As an application of the model, residual deformations of the high rock slopes of the Three Gorges shiplock due to excavation unloading and creep behavior are investigated. By simulating the actual excavation process, the deformation history of a shiplock slope is studied. Good agreement has been achieved between numerical prediction and field measurements. It demonstrates the effectiveness of the presented model in analysis of the creep deformation due to excavation unloading of high rock slopes.     

Elasto-Plastic Bonding of Embedded Optical Fiber Sensors in Concrete

Fiberoptic sensors are increasingly employed for sensing and measurement of strains in structural materials. The glass core of the optical fiber senses the strain through intensity fluctuations, interference, or frequency modulation. Brittleness of the glass core limits practical usage, and therefore, the glass core of optical fibers is coated with low modulus softer protective coatings. The protective coating alters the strain transduction capabilities of the sensor. It absorbs a portion of the strain, and hence only a segment of structural strain is sensed. The study reported here corrects for this error through development of a theoretical model to account for the loss of strain in the protective coating of the optical fiber. The model considers the coating as an elasto-plastic material and formulates strain transfer coefficients for elastic, elasto-plastic, and plastic phases of coating deformation. The theoretical findings were verified through laboratory experimentation. The experimental program involved fabrication of interferometric optical fiber sensors, embedment within mortar samples, and tensile tests in a closed-loop servo-hydraulic testing machine. The elasto-plastic strain transfer coefficients developed in this study were employed for correction of optical fiber sensor data and results were compared with conventional extensometers.     

高频宽带低损耗声表面波滤波器

从分析产生压电漏表面波（ＰＬＳＡＷ）的材料和镜像阻抗连接耦合换能器型双通道低损耗结构入手,介绍了宽带低损耗声表面波滤波器的设计方法,在超高频段上,给出了一些我们的实验数据,得到了宽带低损耗、高阻带抑制的结果     

20信道声表面波滤波器组初探

本文报道我们研制的一种20信道声表面波滤波器组,它有一个输入端,中心在200MHz中频,瞬时带宽100MHz,20个信道输出,每个信道带宽5MHz.各信道的插损为19～20dB,矩形度<2,信道阻带抑制>40dB.器件体积65mm×50mm×13mm,重量<140g.     

一种声表面波滤波器的优化计算方法

介绍了一种新的优化计算方法，从理论上详细论述了这种计算方法，编制了计算机程序，给出了计算结果。     

空气辅助微生物改变地层岩石与流体性质的能力研究

为了提高微生物采油的应用效果,研究了空气辅助对微生物改变地层岩石与流体性质作用机理。通过实验研究空气辅助微生物改变岩石表面润湿性、油水界面张力及微生物降解原油机理,以岩石润湿性和油水界面张力改变为基础,探讨了空气中氧对微生物改变岩石表面和黏附功的影响。实验结果表明,空气中氧可提高微生物菌液改变石英表面润湿角速度,溶氧4.5～5.5mg/L菌液中润湿角降低50.14%～56.94%。4.5 mg/L溶氧条件下,菌液作用后原油界面张力下降80%。与含溶氧5.5mg/L培养的微生物作用后,油质组分增加8.414%,蜡质组分降低7.728%,胶质组分降低5.538%。实验表明,空气辅助可增强微生物改变地层岩石与流体性质的能力,进一步提高原油采收率。     

组织化大豆蛋白挤压工艺参数优化研究

采用二次回归正交旋转组合试验设计方法,分析了国产Ds32-Ⅱ型双螺杆挤压机生产组织化大豆蛋白过程中的模孔直径、挤压温度、螺杆转速和物料含水率4个挤压工艺参数,以密度为指标对其进行了优化.结果表明,4个挤压工艺参数对产品密度均有极显著影响.影响由大到小依次为:模孔直径>螺杆转速>挤压温度>物料含水率.模孔直径和挤压温度的交互作用对产品密度有极显著的负效应(α=0.01),螺杆转速和水分含量的交互作用对样品密度有显著的正效应(α=0.05).在模孔直径2.86～2.87 mm、挤压温度148.72～149.78 ℃、螺杆转速35.24～36.72 Hz和水分含量29.67%～30.00%的挤压条件下,产品密度有95%的可能在0.43～0.45 g/cm3之间.结合设备性能和生产实际,优化的工艺参数如下:模孔直径2.9 mm,挤压温度149 ℃,螺杆转速36 Hz,物料含水率30%.在优化工艺参数下,验证试验所得产品的密度为0.40 g/cm3,基本符合预期结果.