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气水两相流阶段煤基质收缩量预测方法  [PDF]
倪小明,张崇崇,王延斌,王向浩
煤炭学报 , 2014,
Abstract: 为了尽量避免实验室对煤中甲烷气体解吸时煤基质收缩量测试结果的局限性,综合考虑煤层气井排采时气、水两相流阶段煤储层中气、水产出时引起的煤基质压缩变形与解吸收缩,构建具有一定普适性的力学预测模型显得很有必要。基于有效应力、损伤等力学理论,结合煤储层孔隙结构特征,构建了有效应力压缩煤基质的压缩效应模型;根据吉布斯公式、Bangham理论和Langmuir方程,构建了气体解吸引起的煤基质收缩解吸效应模型;基于表面自由能和煤基质弹性能等能量理论、断裂力学理论,建立了压缩效应与解吸效应相互影响下煤基质收缩数理模型。以沁水盆地樊庄区块为实例对气、水两相流阶段的煤基质收缩量进行了计算。结果表明:对基质收缩量的贡献方面,压缩、解吸效应及2者相互影响的4种效应贡献能力处于同一数量级。其中解吸效应影响最大,解吸效应的收缩量计算结果与其他学者实验室的测试结果基本相符。所建煤基质收缩量数学模型能对不同储层地质条件下气、水两相流阶段煤基质收缩量做出较准确的预测。
水下航行器流噪声特性水洞试验研究
Water-Tunnel Experiment about Flow-Noise Characteristic of Underwater Vehicle
 [PDF]

黄桥高,潘光
- , 2015,
Abstract: 在高速水洞中进行了水下航行器流噪声的试验研究,测量了不同头部线型、不同来流速度、不同测试点位置处水下航行器缩比模型的流噪声声压谱特性。试验结果发现,上述因素对模型流噪声均有显著影响:模型头部端面直径越小,头部曲线段越长,其流噪声声压级越小;流噪声声压级随着来流速度的增大而增大;相比头部端面其他位置,驻点处的流噪声声压级最小。同时,运用相似率估算了大尺度航行器的流噪声声压谱,获得了较好的预测值。该研究成果对水下航行器的声学设计具有一定的指导意义。
The flow-noise experiments of underwater vehicle were conducted in the NWPU high speed water-tunnel. The flow-noise sound pressure spectrum characteristics of different underwater vehicle models were tested at different flow velocities and different testing point positions. The experimental results and their analysis show preliminarily that:(1) the flow-noise of underwater vehicle models was significantly influenced by fore-body linetype, flow velocities and testing point positions; (2) the flow-noise sound pressure level was smaller when the front-section diameter of fore-body was smaller and the length of fore-body was longer, the flow-noise sound pressure level increased with increasing flow velocity. (3) compared with other positions of the front-section,the flow-noise sound pressure level of the stagnation point was smallest. The flow-noise sound pressure spectra of large scale underwater vehicle were estimated with scaling law and better estimation value was obtained. We believe that the research results in this paper are helpful in the acoustic design of underwater vehicle
垂直内螺纹管内超临界水的二次流特性
Secondary Flow of Supercritical Water in an Internally Ribbed Tube under High Temperature Condition
 [PDF]

王为术,雷佳,丁雅倩,朱晓静
- , 2016, DOI: 10.13738/j.issn.1671-8097.2016.02.003
Abstract: 运用计算流体力学方法,采用SSG雷诺应力模型对高温条件下垂直内螺纹管中超临界水的二次流特性进行了研究。研究发现:内螺纹的导流作用在垂直于主流的方向产生了很强的二次流场,主流焓的变化对二次流场的基本结构影响很小。内螺纹管周向和径向上的换热系数分布不均,超临界水在螺纹顶部区域的换热效果远好于螺纹底部。在螺纹顶部表面形成的单个旋涡产生一个压力相对较低的区域,传热增强。在大比热区,由于流体热物性急剧变化,换热的不均性更加显著。螺纹底部壁面是内螺纹管周向换热的薄弱位置,其内部结构的优化应重点集中在该区域。
The secondary flow of supercritical water in a vertical internally ribbed tube was studied under high temperature condition using SSG Reynolds stress model. It was found that a strong secondary flow is formed due to the guidance of internal rib and the variation of bulk enthalpy has very little influences on the main structure of the secondary flow. The local flow and heat transfer in the circumferential and radial directions of the tube is not uniform. The average heat transfer near the rib top surface is much better than that near the substrate surface. The individual vortex formed on the rib top surface creates a relative low pressure region and augments the heat transfer. The heat transfer heterogeneity is more pronounced in the great specific heat region (GSHR) due to the drastically changed physical properties. Since the substrate is the weak point of the heat transfer, the optimization of the tube internal structure is suggested to focus on this region.
四流T型中间包控流装置优化的水模拟分析
Optimization of flow control devices in four-strand T type tundish by water simulation
 [PDF]

陈登福,吕奎,谢鑫,龙木军,俞晟
- , 2015, DOI: 10.11835/j.issn.1000-582X.2015.05.018
Abstract: 以某钢厂四流中间包为研究对象,根据相似原理建立了1∶3的物理模型。模型研究了不同结构的挡墙、导流孔和湍流抑制器对中间包内流动特性的影响。实验结果表明,“Y”型挡墙和梯形湍流抑制器(方案F)组合的控流装置能获得相对较优的实验结果。采用方案F的控流装置后,总体的死区比例从原型的23.69%降为8.02%,钢液能得到更为充分的混匀;各流平均停留时间的标准差从原型方案的23.56降低到7.34,各流一致性也得到了明显的改善。
A four-strand T type tundish is studied by using water modeling based on similarity principles. A 1∶3 physical model is built to study the influence of different walls, diversion holes and turbulent inhibitors on flow characteristics. The results show that the flow control device of “Y” type baffle+trapezoidal turbulent inhibitor (case F) apparently favor the flow pattern of the tundish. When the flow control device of case F is equipped, the proportion of dead zone goes down from 23.69% to 8.02% which means that the molten steel could mix well; the standard deviation of the average residence time is decreased by 68.85%, which infers that the consistency among all strands is also improved
五流L型连铸中间包流场优化的水模分析
Water model study on flow optimization of five streams L-type tundish
 [PDF]

马国军,程普红,王晨辉,程常桂
- , 2015, DOI: 10.11835/j.issn.1000-582X.2015.02.013
Abstract: 采用水模型模拟的方法,对某钢厂十机十流连铸机中间包中的一个完全不对称结构的五流L型中间包进行流场优化。试验结果表明:控流最优方案为湍流抑制器T+副导流墙D2+上2孔倾角为25°下靠近后墙单孔倾角30°的3孔主导流墙D1a。采用该方案可使染色剂到达各出口的时间增加,各流响应时间差减小,RTD峰值浓度减小以及高浓度存在的时间延长,各流之间的死区比例减小。
In this paper, the water model method is used to optimize the flow behavior of asymmetrical five streams L-type tundish in a steelmaking plant. The results show that the optimization plan is set up with turbulence suppressor T+ vice guide wall D2+ main guide wall with three holes (D1a) which consists of top two holes with 25° inclination and one hole with 30° inclination below. With this plan, the time which the colorants reach to the outlets increases, the difference of response time in all outlets decreases, the peak concentration of the RTD reduces, the existence time of high concentration liquid steel extends, and the ratio of dead zone in each streams reduces
Effect of Swirling Flow out of Nozzle on Flow Field in Continuous Casting of Billet
旋流水口对小方坯连铸结晶器流场影响的水模拟

JIA Honghai,YU Zhan,LEI Zuosheng,DENG Kang,CHEN Jiachang,HUA Wenjie,REN Zhongming,
贾洪海 于
,,雷作胜,邓 康,陈家昶 华文杰 任忠鸣

金属学报 , 2008,
Abstract: Electromagnetic stirrer was fixed on intermediate zone of the nozzle to make molten steel outflow with swirling flow, reduce dashing depth of molten steel and form a up reversing flow. All of these were to get the mold powder melted, shell solidified and uniform composition in the continuous casting of special steel billet. This paper was to simulate the effect of electromagnetic stirring in submerged entry nozzle (SEN) through setting a swirl blade in SEN of the hydromechanics mode. This method used was to impart swirl to the flow. On the basic of this, the vertical velocity and horizon velocity of liquid level in the model were measured using Ultrasonic Doppler Velocity (UDV).The effectiveness of electromagnetic stirrer and analyzing technological parameter were examined. Following issues were obtained: (1) Swirling flow was in favor of flow field in mold. (2)The dashing depth can be reduced effectively. (3)The reversing flow and heat transmission of meniscus were enlarged. (4)The horizon circulating was formed so the activity of liquid level and the effectiveness of molten slag were increased.
Measurement and Analysis of Aerated Flow Velocity in Scour Hole of High Dam Jet Flow
高坝挑流冲刷坑中掺气水流的流速量测及其特性分析

Li Yongxiang,Yuan Mingshun,Li Chunhua,
李永祥
,苑明顺

实验力学 , 1997,
Abstract: This paper deals with the measurement of time averaged velocity of aerated flow and its turbulent structure by using the hot film technology.This technique is successfully applied for the first time to the measurement of time averaged velocity and impulsive velocity of aerated flow in the scour hole for the Three Gorge spillway dam model.The regression relation between impulsive velocity and impulsive pressure is discussed.The technique proposed in this paper has promoted the current research on fluid flow characteristics in scour holes.It has theoretical and practical significance for the study of energy dissipation mechanism in aerated flow.
空气-水段塞流冷却传热与相界面分布实验研究
Experimental study on heat transfer and interfacial distribution of air-water slug flow in cooling process
 [PDF]

王鑫,董传帅,张晓凌,岳晓庆,何利民
- , 2017, DOI: 10.7523/j.issn.2095-6134.2017.02.017
Abstract: 摘要 针对海底油气管道的散热问题搭建水平气液两相段塞流换热实验装置。研究冷却液温度4℃条件下无相变冷却过程段塞流的换热特性。实验中采用双平行电导探针、热电偶、热电堆等多种测量手段对冷却条件下段塞流的流动和传热参数进行测量。给出对流换热系数与流动界面分布参数变化规律,表明管道上下壁面由于传热不均存在显著的温差。结果还表明,段塞流对流换热系数受气相表观流速影响较小,流体与下壁面之间的对流换热明显强于与上壁面之间的对流换热。
孔眼式量水器  [PDF]
张德友
地质与勘探 , 1965,
Abstract: 孔眼量水器是掌握钻进水量的一种简易装置。我们使用孔眼式简易量水器,准确的掌握了钻进的泵量参数。根据水力学中,液体通过容器壁上的小孔口泄流的速度,与孔口重心以上的水柱高度有关的原理,我们设计了孔眼量水器。孔服量水器是一只多孔口的泄水容器,其构造如图所示。图中,量水管(1)和缓冲室(2)都是
Precision and Errors Analysis of PIV Used for the Watertunnel Flow Field Displaying and Measuring System
PIV系统水洞流场测量准确度与误差分析

RUAN Chi,SUN Chuan-dong,BAI Yong-lin,WANG Yi-shan,
阮驰
,孙传东,白永林,王屹山

光子学报 , 2008,
Abstract: In order to improve the measuring accuracy,the limitations to the detecting precision of the PIV were discussed and the improve methods were given.The experiments were designed to measure the non-model and the ball model flow fields in the watertunnel.The measuring accuracy of the non-model flow field with the flow speed of 6m/s was less than 1.3%.By comparing the theory value and the detecting results of the ball model flow fields,the accuracy of the majority area in the detecting domain was less than 2%,but in the ball boundary and the area beside the link was 6%~8%.In the end,the errors were analyzed for the system future improvement.
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