Investigations on dynamics of bubble in a 2D vibrated fluidized bed using pressure drop signal and high-speed image analysis

2020 ◽  
Vol 395 ◽  
pp. 125129 ◽  
Author(s):  
Yadong Zhang ◽  
Jinbing Zhang ◽  
Yuemin Zhao ◽  
Xiangyu Zhang ◽  
Xuliang Yang ◽  
...  
Keyword(s):  
Image Analysis ◽  
Pressure Drop ◽  
Fluidized Bed ◽  
High Speed ◽  
Vibrated Fluidized Bed

The Pressure Drop at Critical Fluidization of Large Particles in Vibrated Fluidization Bed

2012 ◽  
Vol 550-553 ◽  
pp. 2763-2766
Author(s):  
Xue Jun Zhu ◽  
Jun Deng
Keyword(s):  
Pressure Drop ◽  
Fluidized Bed ◽  
Large Particle ◽  
Particle Diameter ◽  
Future Design ◽  
Vibration Strength ◽  
Bed Height ◽  
Large Particles ◽  
Vibrated Fluidized Bed ◽  
Critical Fluidization

The pressure drop at critical fluidization for two-dimensional vibrated fluidized bed(240 mm×80 mm) was studied, with large particle glass beads of average diameters dp of 1.8mm, 2.5mm and 3.2mm.The effect of the vibration strength, the static bed height and the particle diameter on the pressure drop was analyzed. The results of the study show that the pressure drop decreases with the increase of the vibration strength. It plays an even more prominent part with decreases of the static bed height and the particle diameter. The empirical correlation equations to predict the pressure drop was established, and the results of the prediction was compared with the experimental data, the error is in range of ±10%. The results can provide references for future design and research on the vibrated fluidized bed.

Multiphase Flow Simulation and the Analysis Method of the Pressure Drop in the Vibrated Fluidized Bed

2010 ◽  
Vol 118-120 ◽  
pp. 935-939
Author(s):  
Bai Chun Li ◽  
Wen Qiang Lin ◽  
La Mei Wang
Keyword(s):  
Pressure Drop ◽  
Multiphase Flow ◽  
Fluidized Bed ◽  
Flow Simulation ◽  
Experimental System ◽  
Simulation Method ◽  
Calculation Model ◽  
Coal Particles ◽  
Vibrated Fluidized Bed ◽  
Computational Fluid Dynamics Cfd

This paper designed experimental system and the corresponding multi-particle coal particles experiments. At the same time based on computational fluid dynamics (CFD), we use Fluent as a tool to carry out the corresponding multiphase flow simulation experiments. The simulation results have a good consistency with the experimental results. Ultimately, we acquire the pressure drop calculation model and the simulation method of the multiphase flow pressure drop analysis inside the vibrated fluidized bed.

High-speed brightfield 3-D imaging and 3-D image analysis of thick and overlapped cell clusters in cytological preparations

1994 ◽  
Vol 52 ◽  
pp. 218-219
Author(s):  
Robert W. Mackin
Keyword(s):  
Image Analysis ◽  
High Speed ◽  
Three Dimensional ◽  
Image Data ◽  
Ccd Camera ◽  
Objective Lens ◽  
Array Processor ◽  
Vaginal Smears ◽  
Low Contrast ◽  
Computer Controlled

This paper presents two advances towards the automated three-dimensional (3-D) analysis of thick and heavily-overlapped regions in cytological preparations such as cervical/vaginal smears. First, a high speed 3-D brightfield microscope has been developed, allowing the acquisition of image data at speeds approaching 30 optical slices per second. Second, algorithms have been developed to detect and segment nuclei in spite of the extremely high image variability and low contrast typical of such regions. The analysis of such regions is inherently a 3-D problem that cannot be solved reliably with conventional 2-D imaging and image analysis methods.High-Speed 3-D imaging of the specimen is accomplished by moving the specimen axially relative to the objective lens of a standard microscope (Zeiss) at a speed of 30 steps per second, where the stepsize is adjustable from 0.2 - 5μm. The specimen is mounted on a computer-controlled, piezoelectric microstage (Burleigh PZS-100, 68/μm displacement). At each step, an optical slice is acquired using a CCD camera (SONY XC-11/71 IP, Dalsa CA-D1-0256, and CA-D2-0512 have been used) connected to a 4-node array processor system based on the Intel i860 chip.

Monitoring of the fluidized bed particle drying process by temperature and pressure drop measurements

2021 ◽  
pp. 1-13
Author(s):  
Gabriela Saldanha Soares ◽  
Scarlet Neves Tuchtenhagen ◽  
Luiz Antonio de Almeida Pinto ◽  
Carlos Alberto Severo Felipe
Keyword(s):  
Pressure Drop ◽  
Fluidized Bed ◽  
Drying Process ◽  
Temperature And Pressure

Collision-Free Tool Path Generation for Five-Axis High Speed Machining

2011 ◽  
Vol 474-476 ◽  
pp. 961-966 ◽  
Author(s):  
Li Qiang Zhang ◽  
Min Yue
Keyword(s):  
Image Analysis ◽  
Collision Detection ◽  
High Speed ◽  
Tool Path ◽  
Geometric Model ◽  
High Speed Machining ◽  
Analysis Method ◽  
Geometric Information ◽  
Detection Approach ◽  
Five Axis

Collision detection is a critical problem in five-axis high speed machining. Using a combination of process simulation and collision detection based on image analysis, a rapid detection approach is developed. The geometric model provides the cut geometry for the collision detection and records a dynamic geometric information for in-process workpiece. For the precise collision detection, a strategy of image analysis method is developed in order to make the approach efficient and maintian a high detection precision. An example of five-axis machining propeller is studied to demonstrate the proposed approach. It has shown that the collision detection task can be achieved with a near real-time performance.

A method for measuring the residence time distribution of particles in a fluidized bed based on digital image analysis

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jiamin Li ◽  
Xiaoping Chen ◽  
Jiliang Ma ◽  
Cai Liang
Keyword(s):  
Image Analysis ◽  
Fluidized Bed ◽  
Residence Time ◽  
Digital Image ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Digital Image Analysis ◽  
Color Space ◽  
The Difference ◽  
Accuracy And Repeatability

AbstractTraditional methods for measuring the residence time distribution (RTD) of particles in a fluidized bed are complex and time-consuming. To this regard, the present work proposes a new measurement method with remarkable efficiency based on digital image analysis. The dyed tracers are recognized in the images of the samples due to the difference of colors from bed materials. The HSV and the well-known RGB color space were employed to distinguish the tracers. By enhancing the Saturation and the Value in HSV and adjusting the gray range of images, the recognition error is effectively reduced. Then the pixels representing the tracers are distinguished, based on which the concentration of the tracers and RTD are measured. The efficiency, accuracy and repeatability of the method were validated by RTD measurements experiments. The method is also fit for distinguishing the target particles from multi-component systems consisting of particles of different colors.

Experimental Study of the Mixing and Segregation Behavior in Binary Particle Fluidized Bed with Wide Size Distributions

2018 ◽  
Vol 16 (12) ◽  
Author(s):  
Runjia Liu ◽  
Yong Zang ◽  
Rui Xiao
Keyword(s):  
Image Processing ◽  
Pressure Drop ◽  
Size Distribution ◽  
Fluidized Bed ◽  
Processing Method ◽  
Size Distributions ◽  
Mixing Index ◽  
Image Processing Method ◽  
Segregation Behavior ◽  
Wide Size Distribution

Abstract Detailed understanding the particle mixing and segregation dynamic is essential in successfully designing and reasonably operating multicomponent fluidized bed. In this work, a novel fluorescent tracer technique combining image processing method has been used to investigate the mixing and segregation behavior in a binary fluidized bed with wide size distributions. The particle number percentage in each layer for different gas velocities is obtained by an image processing method. Fluidization, mixing and segregation behavior has been discussed in terms of bed pressure drop, gas velocity and mixing index. Different types of binary particle systems, including the jetsam and the flotsam-rich system, are analyzed and compared. The mixing indexes at different minimum fluidization velocities are also analyzed and compared with other work. The results show that the theoretical minimum fluidization velocity calculated from the bed pressure drop cannot represent the whole fluidization for a wide size distribution binary particle system. The effect of a wide size distribution is an inflection point in the mixing index curve. There is also a dead region in the bottom of the bed that consists of particles with large size and a low degree of sphericity. The particles in the dead region are extraordinarily difficult to fluidize and should be considered in the design of fluidized beds in industrial applications.

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