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A high-speed acquisition and processing system of the laser speckle signal on the magnetic fluid (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China
作者:  
Sun Y.;  Sun Y.;  Wan Q.-H.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
In order to achieve the dynamical detection and real-time analysis of the movement status of the magnetic fluid  according to the difficulties of the detection of the magnetic fluid  established a high-speed acquisition and processing system of laser speckle signal on the magnetic fluid. First of all  the FPGA (EP2C8T144C8N) drived the linear array CCD(TCD1501D) to scan in the corresponding time sequence given by the computer  collected the laser speckle interferometric image in rapid change on the surface of the magnetic fluid  which followed the movement of the magnetic fluid  and the signal collected by CCD was converted into the digital data through the high-speed A/D convertor and stored into the internal buffer FIFO of the FPGA  whose width and depth were designed by the user as required. Then  the FPGA sent the digital signal of the laser speckle interferometric images into the computer through the USB2.0 highspeed differential bus  whose transmission rate can reach 480Mb/s in theory. Finally  the distribution of the laser speckle on the magnetic fluid was messy and random  which carried certain information about the surface of the magnetic fluid  based on the theories of the statistic correlation and the subdivision of images  analysing and processing the laser speckle interferometric images  indirectly got the movement status of the magnetic fluid under the electromagnetic field. The experimental results show that: the High Speed Acquisition and Processing System has the advantage of full-court  non-contact  non-invasive  high-precision and high reliability and so on. The detection resolution of high speed acquisition and processing system is superior to 1m and the sample rate is 3Msps  which basically meets the requirements of the magnetic fluid movement state detection. 2009 SPIE.  
Simulations and experimental studies of diffuser/nozzle pumps (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Precision Mechanical Measurements, August 25, 2008 - August 29, 2009, Hefei/Jiuhua Mountain, Anhui, China
作者:  
Li W.;  Li W.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
An investigation of diffuser/nozzle micropumps is presented. Numerical simulations are done using CFD program ANSYS/Flotran. The simulations show when the opening angel is small  the flow in the diffuser/nozzle is steady  the mass flow is increasing with the adding opening angle. But when the opening angel continues increasing  the pressure grads will be bigger than zero. It means that the static pressure is gradually going up along the diverging direction. The fluid near the wall stops flowing because the velocity decreases rapidly and the dynamic pressure is not big enough to overcome the increasing of the static pressure. Finally the fluid flows reversely from the backward position of higher pressure area  this makes the separation flow of fluid  the diffuser is full of reverse fluid. And this results in the dropping of mass flow at last. The simulations also show that the performance of diffuser with a round inlet is better than that with a sharp inlet. The mass flow of micropumps with different opening angles  different inlets are measured. The experimental results agree well with the simulations. 2008 SPIE.  
Scaling and analyzing the influence of fluid surface of fluid with nano-granular through speckle pattern experiment (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Wang X.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
An optical system with double beam interference system was designed to measure the movement of nano-particles in fluid with laser speckle technology. In order to investigate the influence of the scattering light generated from liquid surface on speckle patterns  the liquid surface contour was dynamically detected by WYKO during nano-particle movement. The result demonstrates that the fluctuation of fluid surface is slight. Meanwhile  in order to further analyze this effect  a piece of ground glass was employed. The process of ground glass to be polished to optical glass was studied and tested continuously using WYKO and laser speckle technology. And then  the speckle patterns generated from kerosene fluid surface were studied. By contrast  the results show that  the fluid surface is transparent to the measurement wavelength. The influence of the surface of fluid can be neglected. Furthermore  the conclusion illustrates that laser speckle technique is an effective and reliable method to study the movement of nano-granular in fluid.  
Direct Numerical Simulation of Particle Dispersion in the Flow Around a Circular Cylinder 期刊论文  OAI收割
JOURNAL OF THERMAL SCIENCE, 2004, 卷号: 13, 期号: 4, 页码: 344,349
Lan LIU; Feng JI; Jianren FAN; Kefa CEN
收藏  |  浏览/下载:20/0  |  提交时间:2013/03/11
Oxygen concentration distribution in an airlift loop reactor 期刊论文  OAI收割
Science in China,Ser.A, 1995, 期号: 01, 页码: 107-115
Li GQ(李国庆); Yang SZ(杨守志); Cai ZL(蔡昭铃); Chen JY(陈家镛)
收藏  |  浏览/下载:15/0  |  提交时间:2013/12/24