Experimental fluid dynamics of particles in a dielectric barrier discharge plasma-enhanced spouted bed

This study proposed the fluidized particles with dielectric barrier discharge (DBD) plasma in a slot-rectangular divergent-base spouted bed and focused on the dynamics of solid particles with the plasma irradiation. Two bed materials (Polypropylene (PP) particles and Polyamide (PA) particles) with same diameter (3 mm) were fluidized in this study. Fluidization parameters included gas velocity (7.4–14.9 m/s), particle amount (100–500), and plasma parameter (apply voltage, 0 and 7 kV) as the applied voltage were investigated here. Particle velocity profiles were analyzed through the methods of particle image velocimetry (PIV) and particle tracking velocimetry (PTV). Results show that the particle velocity was increased with the plasma irradiation, mainly by the enhancement in the vertical direction. The location of the highest particle velocity area related to the fluidization behavior of particles. With the increase of superficial gas velocity, the location of the highest particle velocity area raised along the central line but not reached the top of the solid bed. While the electron temperature of Ar plasma decreased with the addition of particles. Two electric fields (external electric field and surface charge electric field) presenting in the system were assumed to give the reason for the changes of the particle fluid dynamics.     

微量元素Cr、Zr对铜合金性能的影响

分析了纯铜及合金Cu-Cr、Cu-Zr、Cu-Cr-Zr的力学性能、导电性能和耐蚀性能,研究了微量元素Cr、Zr的添加对纯铜性能的影响。结果表明,微量元素Cr、Zr的添加可显著提高纯铜的强度,强化方式为析出强化;时效过程中析出的弥散相从一定程度上阻碍了电子的运动,使合金的导电性能降低;在中性盐雾环境中,纯铜及合金的失重速度随时间延长呈上升趋势,微量Cr的添加可以提高纯铜的耐蚀性能,而微量Zr的添加则使纯铜的耐蚀性有降低的趋势。     

Adjoint operator approach to functional reliability analysis of passive fluid dynamical systems

Reliability analysis of passive systems mainly involves quantification of the margin to safety limits in probabilistic terms. For systems represented by complex models, propagating input uncertainty to get the response uncertainty and hence probability information requires intensive computational effort. Here a computationally efficient method for the functional reliability analysis of passive fluid dynamical systems is presented. The approach is based on continuous adjoint operator technique to generate a response surface approximating the given system model from the sensitivity coefficients. A numerical application of this method to the reliability analysis of heat transport in an asymmetrical natural convection loop is demonstrated. Computational efficiency and accuracy compared with the direct Monte-Carlo and forward response surface methods.     

基于CUDA的大规模流体实时模拟

流体模拟是计算机图形学中一个重要课题。使用基于粒子的光滑流体动力学SPH(smoothed particle hydrodynamics)方法模拟大规模流体的运动需要大量的粒子模拟流体,计算量巨大,传统的方法很难达到实时性要求。为了解决该问题,使用NVIDIA的并行计算架构CUDA(Compute Unified Device Architecture)将SPH方法的全部处理过程在GPU上实现,充分利用了GPU并行计算的性能优势。使用Z-order排列改进已有的并行邻域搜索算法,并通过优化数据结构及存储器分配,有效缓解了SPH方法在GPU架构上的性能瓶颈。实验结果表明,该方法能实时逼真地模拟大规模流体,与已有的GPU方法相比处理速度有显著的提升。     

重油催化裂化装置全流程动态仿真培训系统

应用机理分析，开发了重油催化裂化装置反应再生系统非线性状态空模型，它包括了不同完全再和一过程特性的描述；运用非平衡级原理，直接计算塔器内部汽液两相传质，传热，建立了主分馏塔数学模型。     

一个SPH流体实时模拟的全GPU实现框架

怎样实时地进行高度逼真的大规模流体模拟是图形学要研究的一个重要内容。流体的模拟由物理计算、碰撞检测、表面重构和渲染几个部分组成,因此有大量工作针对流体模拟中的各个部分算法进行GPU加速。提出一整套基于GPU的SPH流体模拟加速框架。在利用平滑粒子动力学(SPH)求解Navier-Stokes方程的基础上,借助基于GPU的空间划分PSS(Parallel Spatial Subdivision)来大幅度提升粒子碰撞的检测速度。同时,设计一种基于几何着色器(Geometry Shader)的流体表面信息的重建算法,并进一步地实现基于索引的优化,使得在流体表面重建过程无须遍历不包含表面的区域。实验结果表明,该方法能实时模拟出具有较好真实感的流体场景。     

基于串级控制的PID算法在调压系统中的应用

以餐饮废油连续化试验设备为背景,在分析超临界反应原理的基础上,提供了一种系统搭建的思路和静态高压的实现技术。本系统融合了流体控制技术、信号检测技术、逻辑控制技术和PID控制算法的研究。运用经典的闭环控制理论,本系统使精度不高而成本相对比较低的电子元件组成了一个精确的化学反应调压控制系统。     

On the numerical solution of a structured nonsymmetric algebraic Riccati equation

A class of nonsymmetric algebraic Riccati equation, where one of the two linear coefficients is block diagonal, is studied. These equations arise in the modeling of an adaptive MMAP[K]/PH[K]/1$MMAP\left[K\right]/PH\left[K\right]/1$ queue. Some theoretical results are proved, and two new algorithms are introduced that exploit the diagonal structure of the linear coefficient.     

功图计量与工况智能分析技术在长庆油田的应用

本文从功图计量与工况智能分析技术的技术原理、有杆抽油系统数学模型的建立、泵功图的计算、有效冲程的识别及计算结果的修正五个方面对该技术进行了详细的阐述,重点介绍了功图计量与工况智能分析系统的构建及其拓展的功能,实现了生产数据的实时采集、产量自动计产、油井远程监控、油井故障诊断、动液面实时监测、系统效率实时监测、报表自动生成等功能,简化了流程,降低了投资、减少了用工总量,提高了油田数字化管理水平,为建设数字化油田,实现5000万吨目标提供技术支撑。