摘要：It is very important to analyze and study the motion process of droplets impacting superhydrophobic surface, which is of great significanee to understand the mechanism of superhydrophobic surface and guide the design and manufacture of superhydrophobic surface. Taking by three-dimensional volume of fluid (VOF) simulation coupling coupled level set (CLS) algorithm, on the one hand, we simulate the morphological changes in the process of droplet impingement, as well as the internal velocity and the pressure distribution;on the other hand,we focus on the effects of droplet impact velocity, surface wettability, surface tension on the dynamics of the droplets. The CLSVOF model inherits the advantages of the VOF model for accurately constructing the phase interface and inherits the advantage that the level set can accurately calculate the surface tension, which improves the accuracy of the calculation of the droplet impact on the superhydrophobic surface. The computed results distinctly demonstrated there were four stages: falling, spreading, shrinking and rebounding. The time history of each stage agreed well with the pictures captured by high-speed camera, which indicated the computational fluid dynamics scheme was effective. Moreover, the motion mechanism of the droplets impacting on the solid surface is elaborated, which was helpful to control the solid-liquid interface to achieve a variety of solid interface characteristics.

摘要：科学计算与工程应用对高性能日益增长的需求将推动高性能计算进入后E级时代。高性能处理器作为超级计算系统核心部件,其架构设计对提高系统性能至关重要。首先介绍后E级时代高性能处理器架构设计的3个目标,即性能有效扩展、资源高效利用和适应多种应用。其次,提出标量运算众核主芯片连接应用加速从芯片的Massa处理器架构,通过计算资源分布和应用定制硬件的结合,满足后E级时代高性能处理器架构设计的目标。最后,讨论了Massa架构未来需要重点研究的若干问题。

摘要：为固体激光器设计了一种新型内部结构——扰流柱结构的冷却热沉,采用计算流体力学(CFD)方法对此水冷热沉的三种典型设计方案以及传统的空腔结构和等截面小通道结构热沉分别进行了数值模拟,据此研究了冷却水流量对各种方案的增益介质最高温度、冷却面温度分布以及热沉的压力损失等特性的影响。在相同传热量和相同冷却水流量前提下,等截面小通道热沉和扰流柱热沉的传热特性都明显优于空腔结构热沉。与等截面小通道水冷热沉相比较,扰流柱热沉传热热阻更小,而流动压力损失较大。数值模拟结果表明扰流柱热沉传热性能优于传统的两种热沉(空腔结构和等截面小通道结构)设计方案,具有更好的冷却效果。在较高流量下工作时,扰流柱热沉传热性能略优于等截面小通道热沉,在较低流量下工作时则显著优于等截面小通道热沉。

摘要：为提高潮流能利用效率,基于叶素-动量理论(BEM),给出了Wilson模型在水平轴潮流能水轮机设计上的应用。采用CFD技术计算对设计的水轮机进行水动力特性分析,计算其在不同叶尖速比下的功率特性。在此基础上,对叶片沿展长方向的功率分布和三维绕流特性进行分析,并采用二维计算方法预测对应三维工况下各截面处的流场特性。计算结果表明,水轮机的工作特性满足对功率和效率的要求,说明了设计方法的可靠性;同时绕流特性分析也显示了二维模拟的局限性,尤其在叶根、叶尖部位失真较大,这说明三维效应对水轮机输出功率和流场性能有着显著的影响。

摘要：以SAE(美国机动车工程师学会)模型为研究对象,采用计算流体力学数值模拟方法研究非光滑表面布置位置对车身气动性能的影响.通过对钝体模型的不同位置(侧部、底部、顶部、尾部)布置凹坑型非光滑表面,计算钝体模型的空气阻力系数,比较光滑表面与非光滑表面速度矢量、压力以及湍动能,分析了非光滑表面气动减阻机理和减阻效果差异的原因,根据分析结果得到在模型的侧部、顶部、尾部和底部布置非光滑表面均能起到减阻作用,尾部非光滑表面的减阻效果最明显,减阻率达到5.73%.

摘要：A novel CAD method for tooth profile based on the gearing feature has been proposed in this paper, and this method could be applied to the variable transmission ratio and three-dimension situation. The two pitch curves of the two gears can be generated due to the given transmission ratio. The tooth profile curves are formed in each coordinate system of its pitch curve by the gearing process. Finally, the tooth profile could be extracted and translated into a real dimension by CAD method. It is provided a simply thought for tooth profile design to avoid so much complicated mathematical reasoning.

摘要：This article introduces a new biomedical / open surgical instrument to assist surgeon in applying surgical clips to patient’s body tissue and blood vessel during surgical processes. The new clip delivery system is designed to better the clip’s distal advance through internal clip channel, jaw guiding track, and all other transition areas to keep surgical clip from accidental shooting out during clip’s distal move into jaws. Currently the clip distal move in normal surgical instrument is usually driven by compression springs and some complains of clip accidental drop-off were recorded in surgical procedures. Because higher request of dimensional tolerance and better component surface quality are needed in case the compression springs are used as driven force, a little dimensional devia-tion or less qualified part surface produced from manufacturing processes will potentially cause surgical clip device malfunction or misfiring of the clips. It is clearly known that the jaws can seriously sever or damage patient’s blood ves-sel or body tissue if there is no clip inside the jaws due to accidental clip drop-off, when surgeons close instrument handles. The improved internal system design in this new open surgical instrument can prevent clip from accidental drop-off because of well guided and controlled clip distal move through internal clip channel and track. Besides the operational force to fully form clip is lower than existing surgical clip devices due to better mechanical advantage in this new instrument design. In addition to the above, manufacturing and product cost can be decreased since lower requirement of dimensional tolerance and surface quality of instrumental parts is allowed in this new surgical instrument design. This new instrumental prototype is build upon the analysis of computer aided modeling and simulation to prove its good mechanical advantage, feasible function, reliable performance. The preliminary results of instrument fir-ing force from both comp