圆柱尾流

篇文章由山东普创工业科技有限公司为您讲解圆柱形复合罐端盖脱离力测试：圆柱形复合罐端盖脱离力测试标准：GB/T 10440——2008

本文特别针对圆柱形锂离子电池的径向导热系数，开展了测试方法研究。在不破坏电池和只有电池圆周外表面的边界条件下，分别采用了恒温和恒流两种测试方法建立了相应的测试模型和解析表达式，并通过有限元仿真来验证了测试模型和解析表达式的准确性，为测试仪器的设计提供了有效指导，为在其他规格锂电池热性能测试中的推广有重大意义。

采用英国Litron公司LPY 703-200型, 200 Hz PIV激光器作光源。两台Photron 1024 PCI型高速相机作为成像组件，构成一套高速时间分辨粒子成像测速系统。同时用多台高速相机记录两种食虫性蝙蝠飞行的运动学特征。同步同时测量运动学特征和尾流结构。并分析其特点规律。

本文针对圆柱形锂离子电池整体导热系数测试方法，评论性概述了近些年的文献报道，研究分析了导热系数测试方法的特点，总结了圆柱形锂电池各向异性导热系数测试中存在的问题和面临的挑战，从热分析仪器市场化角度提出了迎接这些挑战的技术途径和新方法。

A survey is conducted to quantitatively visualise the wake flow behind a circular cylinder at Reynolds numbers of 180 to 2500. A time-resolved tomographic PIV method is used to measure thesequence of three-dimensional vector fields evolving in time. The attention is focused upon the unsteady 3D wake organization with the interaction of primary rollers (Karman-Benard) and the secondary vortices resulting from 3D instability of the vortex wake.

采用两台LaVision ImagerProX4M相机和两台CMOS相机构成一套可以测量两个互相垂直平面的2D2C和2D3C速度矢量场的粒子成像测速系统。用于带侧后缘锥度方型背车辆低频尾流动力学研究。

采用LaVision的DaVis 8.0.8图像采集和分析处理软件平台，加上Imager pro HS 4M型相机，构成粒子成像测速（PIV)系统。利用该系统对从一个容器中掉落的圆柱形颗粒的流动分布进行了测量，并与离散元法模型法进行比对，从而优化离散元法模型法

漆膜圆柱弯曲试验仪是检测仪器，用于测定色漆和清漆的涂膜柔韧性，是衡量涂料性能的主要指标之一，对于涂料品种的选择。

The wakes of wall mounted circular cylinders of very lowaspect ratio have been investigated in a wind tunnel. Besidesplanar PIV, also high resolution tomographic PIV was usedto capture the flow phenomena downstream of the cylinder.By changing the velocity U￥ and the cylinder height h at aconstant aspect ratio L = h=D, a wide database of differentflow conditions was obtained. The resulting relative height ofthe boundary layer thickness d was 0:6 h=d 2:5, while theReynolds number based on the length l between leading edgeand cylinder centre Rel was 57 000 Rel 188 000. A pair ofcounter-rotating vortices was found in the wake of the cylinder.The rotation sense is such, that in the center of the wake apositive vertical velocity component results. Also horseshoevortices were found next to these trailing vortices. The relativeheight of the incoming boundary layer has a large impact on thedevelopment, strength and dissipation of the vortex system.

We study experimentally the impulse response of a cylinder wake below the critical Reynoldsnumber of the Bé nard–von Ká rmá n instability. In this subcritical regime, a localized inhomogeneousregion of convective instability exists which causes initial perturbations to be transiently amplified.The aim of this work is to quantify the evolution resulting from this convective instability usingtwo-dimensional particle image velocimetry in a hydrodynamic tunnel experiment. The velocityfields allow us to describe the evolution of wave packets in terms of two control parameters: theReynolds number and the magnitude of the imposed perturbation. The temporal evolution of energyexhibits a transient algebraic growth at short times followed by an exponential decay.

纸面圆珠笔迹，因其颜色深、纸面反射率低等诸多原因，在FTIR显微镜上用反射方式直接对其检测效果很差。在FTIR显微镜上加用ATR物镜，利用物镜与纸面笔迹接触的ATR检测原理，获得了十分满意的圆珠笔迹红外光谱。这种检测广东既得到了清晰的红外光谱图，提供了丰富的笔迹信息，又保护了被检样品的原始性。

圆珠笔和笔芯抗泄漏性检测方法与减压仪器介绍摘要：圆珠笔是现在生活以及商务活动中必不可少的一种文具工具，经常会在使用中发现圆珠笔和笔芯的墨水泄漏，不但影响正常使用，更会污染纸张或衣物。本文将结合济南兰光机电技术有限公司的MFY-01密封试验仪，对圆珠笔和笔芯的抗泄漏性能检测进行简单介绍。是笔芯质量的重要指标。关键词：笔芯，泄露，笔芯泄漏，密封试验仪，减压仪

1, a=radius). The experiments use conventional test methods in conjunction with Stereo Particle Image Velocimetry (SPIV) measurement techniques to evaluate the flow in the boundary region of a small diameter flexible cylinder towed in the high speed towing basin at the Naval Surface Warfare Center Carderock Division (NSWCCD). The flexible cylinders are approximately neutrally buoyant and have an initial length of 152 m and radii of 0.45 mm and 1.25 mm. The first objective for this experiment is to evaluate the streamwise development of wall shear stress (τw) and momentum thickness (θ) in axisymmetric turbulent boundary layers using drag measurements at 3.1, 5.2, 9.3 and 14.4 m/s for comparison to existing data. The second and primary objective for this experiment is to determine the streamwise development of the axisymmetric boundary layer flow and to evaluate relevant boundary layer parameters at 3.8, 7.7, 12.9 and 15.4 m/sec using SPIV images acquired over the entire length of the cylinders. Drag measurements reveal that the wall shear stress is large and that the momentum thickness grows slowly when compared to flat plate boundary layers. The velocity field data shows that the boundary flow remains turbulent over the entire length of the flexible cylinder and that the turbulent profile is different from that of flat plate boundary layers.

采用德国LaVision公司的软件平台和四台Imager SX 4M型CCD相机。构成一套层析PIV处理系统。并利用这样的系统对受到漩涡诱导振动（VIV）影响的系留球体尾流进行了Tomo-PIV测量。

本文通过对水性圆珠笔和笔芯抗漏性能的检测，介绍了一款专业用于笔芯泄漏性能的检测仪器--山东普创工业科技有限公司自主研发生产的LT-02P密封性试验仪。

采用德国LaVision的Imager Pro X4M CCD相机和蔡司ZEISS 50mm f/2 Makro 镜头，测量了亚音速高马赫数跨音速涡轮叶栅尾流的2D2C速度矢量场并和五孔探针的测量结果进行了对比分析。

建立了法庭科学中蓝色圆珠笔色痕的激光剥蚀电感耦合等离子体质谱鉴别方法.对95种不同来源的蓝色圆珠笔进行了分析!依据所含金属元素种类的差别将,95种圆珠笔分为34类,其中26类圆珠笔根据元素种类的差别可直接区分!其余8类依据元素间响应值之比进行区分!对字痕载体纸张的考察结果表明了纸张对检测结果无影响.实验结果表明方法重现性良好!精密度10%,与传统分析技术相比!本方法可获得更好的鉴别结果,95种蓝色圆珠笔中有88种可使用该方法有效鉴别.该方法简便快速"精密度良好"对样本宏观无损!适合法庭科学对蓝色圆珠笔鉴定的需要.

采德国LaVision公司的两相机2D3C立体PIV测量系统和集成一体化的4台相机构成的MiniShaker测试系统，对水下导管螺旋桨尾流流场进行了测量和理论分析。

提出了一种基于LA-ICP-MS方法的蓝色圆珠笔墨水的鉴别方法。在没有任何样品准备的情况下，从21支已知来源的蓝色钢笔中切割并测量了含有墨迹的普通办公用纸的一小部分。*步，将Mg、Ca和Sr作为内部标准(ISs)，用于元素强度的归一化和背景信号的消去。然后，设计具体的标准，并采用识别目标元素(Li, V, Mn, Co, Ni, Cu, Zn, Zr, Sn, W, Pb)，结果独立于目标元素，在98%的案例中被选择，并允许对样本进行定性聚类。第二步，利用基于先前识别目标的元素相关比(墨水比)，通过多元统计分析(MANOVA、Tukey’s HSD、T2 Hotelling)获得质量独立强度，并进行两两比较。这种处理提高了辨别能力(DP)，提供了客观的结果，实现了不同品牌之间的完全区别，笔墨与相同品牌之间的部分区别。设计的数据处理，加上多元统计工具的使用，代表了一种容易和有用的工具，以区分蓝色圆珠笔墨水，几乎没有样品破坏和不需要方法校准，因为它的使用可能有利于法医实践的立场。为了检验这一程序，它被用来分析真实的手写的有问题合同，这些合同以前是由西班牙民警刑事主义服务处法医文件考试司研究的。结果表明，所有被质疑的墨水条目都聚集在同一组中，与文档中剩余的墨水不同。

The focus of this study is an experimental apparatus thatserves as a model for studying blood flow in a total artificiallung (TAL), a prototype device intended to serve as a bridge tolung transplantation or that supports pulmonary function duringthe treatment of severe respiratory failure. The TAL consistsof hollow cylindrical fibers that oxygen-rich air flowsthrough and oxygen-poor blood flows around. Because gasdiffusivity in the TAL is very small, a convection mechanismdominates the gas transport, which is why we focus on thevelocity around the fibers (modeled as a 0.05-cm-in-diameterand 5-cm-long cylinder). We designed a low-speed watertunnel to study the flow mechanism around the cylinder,across which the flow is generated by a linear actuator thatallows different flow patterns to mimic the flow in a TAL. Wetested the flow in the test section by numerical simulation andby the particle image velocimetry method to study the flowprofile. The results show a uniform flow near the centerline ofthe water tunnel where the cylinder is placed. This decreasesthe effects of free-stream turbulence in the shear layers andreduces the uncertainty in determining the flow patternsaround the cylinder. Knowledge gained from the flow aroundone cylinder (fiber) is beneficial for understanding vortexformation around multiple cylinders. We present a summaryof vortex formation behind a cylinder for Reynolds numbers(Re) of 1, 3, and 5 and Stokes numbers (Ns) of 0.18 to 0.37 results show that higher Re and Ns favor vortex formation.These findings regarding the parameter range for vortex formationmay provide principles for designing artificial lungs toenhance convective mixing. We anticipate that the pulsatileflow circuit presented here can be used to mimic the flow notonly in TALs but in other physiological systems.

In order to avoid model support interference, the flow over cylinders of varying fineness ratio (length/diameter) aligned with the free stream were examined using a magnetic suspension and balance system. Thedrag coefficient variation of a right circular cylinder was obtained for a wide range of fineness ratios. ParticleImaging Velocimetry (PIV) was used to examine the flow field, particularly the behavior of the leading-edgeseparation shear layer and its effect on the wake. Reynolds numbers based on the cylinder diameter rangedfrom 5x104 to 1.1x105, while the major portion of the experiment was conducted at the ReD= 1.0x105. For themoderately large fineness ratio, the shear layer reattaches with subsequent growth of the boundary layer,whereas over shorter cylinders, the shear layer remains detached. Differences in the wake recirculation regionand the immediate wake patterns are clarified in terms of both the mean velocity and turbulent flow fields,including longitudinal vortical structures in the cross-flow plane of the wake. The minimum dragcorresponded to the fineness ratio where the separated shear layer reattached at the trailing edge of thecylinder. The base pressure was obtained with a telemetry technique. Pressure fields and aerodynamic forcefluctuations are also discussed.

The unsteady organization and the evolution of thecoherent structures within the immediate wake of the sharpsymmetric trailing-edge of a NACA0012 airfoil is investigatedusing two-component (2C) and tomographic particle imagevelocimetry (Tomo-PIV). The inspection of the Tomo-PIVresults showed new vortical structures, introduced here ascounter-hairpin vortices, evolve in the wake region to directthe turbulent mechanism towards recovery of the wake deficit.These vortical structures are topologically similar to thehairpins of a turbulent boundary layer as they appear to be Ushapedbut with inverted orientation. The spanwise portion ofa counter-hairpin vortex is in the vicinity of the wakecenterline and the legs are inclined at an approximately 60degree to the wake axis in the downstream direction. Theypartially wrap around the high speed streaks and frequentlysweep the high-speed flow towards the wake centerline. Apattern recognition algorithm is applied to establishcharacterization based on an ensemble averaged counterhairpinvortex. The formation mechanism of the counterhairpinvortices is attributed to the shear layer produced alongthe wake centerline by the neighboring of a low and a highspeed streak which promotes formation of spanwise vorticesthat form the vortex by connection to quasistreamwisevortices.

对于单端密封的样品,将导气密封装置插入样品未封合端,并套紧封严 对于两端均已密封的样品,用能在一侧罐盖开合适的导气孔而不损坏密封部位的工具开孔,将密封装置插人试样并套紧封严

对于单端密封的样品,将导气密封装置插入样品未封合端,并套紧封严 对于两端均已密封的样品,用能在一侧罐盖开合适的导气孔而不损坏密封部位的工具开孔,将密封装置插人试样并套紧封严。

迄今为止，基于吸附势理论的HK法（狭缝孔）、SF法（圆柱孔）和CY法（笼形孔）已用于各种多孔材料的孔隙结构评价，基于毛细管凝结理论的 INNES 方法（狭缝孔）和 BJH 方法 （圆柱孔）等经典的孔径分析方法，应用于中-大孔范围内孔径分析，这是由于其孔结构的不同。另一方面，近年来，人们开始关注通过计算机模拟方法来评估孔结构，如NLDFT（非定域密度泛函）法和GCMC（巨正则蒙特卡洛）法等，这两种方法用一个统一的理论从微孔到中-大孔进行全孔分析。即使对比经典和新的孔径分布分析法，从同一吸附等温线中获得的孔径大小峰值和孔径分布是不同的，因为每个理论得出的填充压力不同。

The wake of a circular cylinder at Re = 2700 is investigated by means of Tomographic PIV(Tomo-PIV), a recently developed three-dimensional velocimetry technique. The paper presents theprinciples of Tomo-PIV and discusses in details the implementation of the technique to the experimentalconditions. With a measurement volume of approximately 40x40x10 mm2 two configurations are chosen inorder to describe both the 2D wake features and the span wise organization of secondary rollers dominatingthe 3D flow organization. The present data allow to directly evaluate the measurement error imposing massconservation inside the volume (viz. solenoidal velocity field). The visualization of the wake instantaneousstructure is obtained by means of vorticity vector magnitude iso-surfaces, or decomposing the vorticity in thespan wise and stream-wise(normal)/bi-normal component, which return the separate contribution of theKármán rollers and the interconnecting structures between them respectively. The properties of thesecondary rollers are given in terms of span wise wavelength, peak vorticity, vorticity stretching and theirsize and shape. A value of the span wise wavelength λz/D = 1.2 is recurring and the rollers organization intopairs is found to be similar to the instability Mode B occurring in lower Reynolds number wakes investigatedwith previous studies.

刚性试验仪器:能通过施力推杆将最大至60N(精度为士0.1N)的力,向下垂直作用在针管上。施力推杆的下端是由一个互成60°夹角的楔形和曲率半径为1 mm 的圆柱面组成,其推杆宽度至少5 mm

本文介绍了岛津台式X射线CT系统XSeeker 8000设备对整个注塑连接器进行三维无损观察和分析。先用透视功能大致观察内部结构，再使用CT三维观察注塑连接器中的内部结构并导出STL格式。通过VG选配模块对圆和圆柱进行测量、设计件与实物进行比较和壁厚分析。

三七，中药名，为五加科植物三七的干燥根，具有化瘀止血，活血定痛的功效。主治出血症，跌打损伤，瘀血肿痛。主根呈类圆锥形或圆柱形，长1~6cm，直径1~4cm。表面灰褐色或灰黄色，有断续的纵皱纹和支根痕。顶端有茎痕，周围有瘤状突起。体重，质坚实，断面灰绿色、黄绿色或灰白色，木部微呈放射状排列。气微，味苦回甜。主产于云南文山州各县，文山县、砚山县、马关、西畴、广南、麻栗坡、富宁、邱北等，另广西田阳、靖西、田东、德保等地也有种植。为检测三七中的多种重金属元素含量，选择微波消解对其进行前处理，探索最适合的消解参数，该方法还有回收率高、空白低等特点，有利于后续对多种无机元素的快速准确测定。

评定和检验涂层结合力的方法很多，可分为定性和定量两种检验方法定性检验方法:根据法层的种类和法件的使用环境,涂层的定性检验可选择弯曲、铿摩、冲击、刻痕、加热要冷、杯突等多种方法