Dissertation > Excellent graduate degree dissertation topics show

Numerical Study of ISA furnace hydraulics model based on CFD and fractal theory multiphase mixing effect

Author: XuJianXin
Tutor: WangHua;CaiGuangCheng
School: Kunming University of Science and Technology
Course: Computational Mathematics
Keywords: Fractal dimension Numerical simulation ISA furnace Mixing effects Image analysis
CLC: TP391.41
Type: Master's thesis
Year: 2010
Downloads: 72
Quote: 0
Read: Download Dissertation

Abstract


In this work, multi-phase mixing problem of hydrodynamic model Isaac furnace is investigated by fractal theory and CFD (Computational Fluid Dynamics) technology. First, gas-liquid-solid three-phase mixing hydrodynamics model of Isa furnace is established using the Fluent software.A new method is proposed combined with digital image processing techniques, theory of fractal dimension and the CFD numerical simulation technique. It was used to predict the mixing time of Isa furnace hydrodynamic model.In recent years, computational fluid dynamics simulation has a significant effect on mixing process of multiphase flow in stirred tank.So, a large number of repeated experiments can be avoided,it not only saves the cost of the experiment, but also gains the data which you can not get from experiments.It gets more and more widespread attention and application. At present, the main extensive application business software is ANSYS, CFX, FLUENT, COMSOL and so on.In this paper, gas-liquid-solid three-phase mixing effects of the Isa furnace hydraulic model in company A are investigated by the commercial software FLUENT, during the process of modeling, First,we made comparative and analysis of how to selected the multi-phase flow model, in FLUENT, there are three Euler-Euler multi-phase flow model, Eulerian model, Miture model and Volume of Fluid model, In order to compare the results of simulation and experiment, we have proposed the edge detection algorithm which based on the golden section, it was used in bubble contour extraction for water model experiment image, The result shows that the VOF multiphase flow model share the same momentum equation for different fluid composition, it recorded the proportion of volume rate of fluid composition in each calculation cell which in the the process of calculation, achieve the surface tracking between the phase and phase better. Combination of the method which proposed in this paper, it can achieve its quantified of the degree of mixture uniformity in complex process of phase transition of the mixed multiphase flow, it is characterization of mixing time. For the research about prediction of the mixing time of multiphase flow in Isa furnace chamber, we established a two-dimensional cold model first, in view of the easily model calculation and convergence on calculation process, by analysis of the calculating result, we found the two-dimensional simplified model have some limitations, it can not reflects the cross-section of the phase transition in three-dimensional model accurately and fully, so we further established the three-dimensional model, by tracking the phase transition picture of a cross-sectional drawings under the gun, we made gray image transformed and five consecutive corrosion operation processing for every picture we gathe, and calculate the box dimension separately, fit the slope value of box dimension after etching by least-square method, and then make further analysis of the evolution of P values over time (Namely:the slope of the box dimension) by the time series analysis method.In the design of experiments, we have considered the research of different sizes of jet flow (Q=500L/h, 1000L/h,1500L/h,2000L/h) and immersion depth of different jetting gun (H=5cm,5.5cm,6cm,6.5cm,7cm), then we obtain the shortest mixing time T (namely: the intersection point or nearest point of the time series evolution curve of P value and the oscillation average P value in cell after mixing) by the method of average of P,which could describe the uniformity of multi-phase mixing more accurately and clearly.Both the classical box-counting dimension method and our mehtod are basically matched with the observations and calculated values which obtained by hydraulic model test, and it played a certain guiding role in optimizing the reaction progress and improving the mixing efficiency of A company’s Isa furnace bath. It is not hard for us to get the real-time sectional image of changes in the internal structure for non-transparent material as the matured and improved of electric properties tomography (EPT), so the hydrodynamic model test have a good reference value,our method not only can forecast the mixing time, but also can be applied to measure the mixing time in practical engineering. It have a strong adaptability on the evaluation problem of the general multiphase flow mixing effects, we believe that it will have a good application potential in the field of metallurgy.

Related Dissertations

  1. The Setting Bases of Working Pressure in LNG Systems and Orthogonal Experiment Design of Heat Exchangers,TQ051.5
  2. Study on Springback of High-Strength Steel Stamping,TG386
  3. Numerical Simulation and Experiment on Hydroforming of Cups with Controllable Radial Pressure,TG386
  4. Research on Technology and Mechanism of Joining Cemented Carbide to Carbon Steel,TG454
  5. Image Analysis System of Metal Transfer of Gas Metal Arc Welding,TG444
  6. Numerical Simulation of Film Cooling in Turbine Cascade with Non-Axisymmetric Endwall Method,V231.3
  7. High Speed Aerodynamic Convection and Coupled Heat Transfer of Complicated Bodies,V215.4
  8. The Analysis on Characteris of Vibration Source about Vertical Vibration of Surrounding Environment Induced by Rail Transit,U211.3
  9. Study on the Heat Transfer Characteristics of Particle Cluster in Circulating Fluidized Bed,TK124
  10. Numerical Simulation of SNCR Process of a 600MW Utility Boiler,TK222
  11. Numerical Simulation of Biomass Direct Reburning,TK16
  12. Numerical Simulation on Pulverized Coal Combustion Process in a 670T/H Tangential Firing Furnace,TK224.11
  13. Numerical Simulation on the Combustion Process in the Furnace of a 1000MW Lignite-Fired USC Boiler,TK224.11
  14. Study on Gas-Solid Two-Phase Flow in Spouted Beds,TK173
  15. Experimental Study and Numerical Simulation on Aerodynamic Field of Tangential Bias Swirl Burner,TK223.23
  16. Characteristic Study of Combustion in Central Reverse Flame Chamber,TK223.21
  17. Numerical Simulation and Contrastive Analysis of Labyrinth Seals and Leaf Seals,TK263.2
  18. Numerical Study on Phosphorus Distribution in Water Environment of the Three Gorges Reservoir,X832
  19. The Design and Performance Simulation of External Valve Small Displacement Pump,TE933.3
  20. Analysis of the Impact of Tailings Dam Stability under Seepage Role,TV649
  21. Research and Application on Field Framework Extention Methods Based on OSGi,TP311.5

CLC: > Industrial Technology > Automation technology,computer technology > Computing technology,computer technology > Computer applications > Information processing (information processing) > Pattern Recognition and devices > Image recognition device
© 2012 www.DissertationTopic.Net  Mobile