Dissertation > Excellent graduate degree dissertation topics show

Three-dimensional Numerical Simulation of the Combustion Flow of the Multi-Jet Flame Combustion Chamber

Author: NingJingWei
Tutor: LiChunZhong
School: East China University of Science and Technology
Course: Material Chemical Engineering
Keywords: Multi-jet Flame Combustion Chamber Three-dimensional Flow Numerical Simulation Nanoparticles
CLC: TQ052
Type: Master's thesis
Year: 2012
Downloads: 49
Quote: 0
Read: Download Dissertation

Abstract


In the process for the preparation of nanoparticles by gas-phase flame synthesis, the structure of the combustion chamber and the flame structure have great influence on the distribution of the thermodynamics and kinetics parameters which are required by the nucleation and growth of the particles. And then the thermodynamics and kinetics parameters decide the morphology, structure and the performance of final product. The design and optimization of the combustion chamber structure are always the basis and key of process research, but many parameters inside the combustion chamber are not easy to obtain through experiments, which brings a lot of inconvenience for the design of the chamber structure. Therefore, it is of great theoretic value and practical significance to predict the flow field inside the reactor through numerical simulation method.In this thesis, we design the multi-jet flame reactor by analyzing the air dynamics in the reactor and numerically simulate the flame inside the combustion chamber by using GAMBIT and CFD commercial software FLUENT. The main research work carried out includes:1. We use the GAMBIT software to build the physical model of the multi-jet combustion chamber and divide the grids. The grid structure is Tetrahedron and the total grid number is 6.45 million. According to the structure of the reactor, the operation conditions and the application scope of the mathematical models in the software FLUENT 6.3, we finally determine the reasonable mathematical model to simulate the combustion process inside the reactor. We use the standard k-εturbulent model, the EDC model to calculate the chemistry reaction rate and the DO model to calculate the gas heat radiation.2. We numerically investigate the effect of many engineering factors on the flame structure, temperature profiles, velocity profiles, species distribution and etc. The factors include the flame configuration, the shapes of the nozzle, the radiation heat transfer, the air film speed and different wall boundaries. By analyzing the simulation results, we get the following conclusions. The reaction temperature has a difference under different flame configuration. The effect of the radiation model on the heat transfer is significant and the flame peak temperature becomes lower by adding the radiation model. The temperature in the reactor decreases as the tangential purge gas enters the reactor. Compared to a single reaction step, the predicted temperature in the reactor is lower by using complex reactions, but the velocity field just changes little. When the reactor wall is set for convection wall, the temperature near the reactor wall is lower and the peak temperature along the center axis is also much lower than the adiabatic wall boundary, which mainly takes place in the lower temperature area.3. In the multi-jet flame reactor, anhydrous AICl3 powder was used as precursor, Al2O3 nano-particles were successfully prepared with different morphology and crystallinity. Based on the experiment, we simulate the flow field in the multi-jet combustion reactor and mainly investigate the flame temperature distribution, velocity distribution and species concentration in the combustion reactor under different flame configuration. At the same time, the effects of the flame radial temperature on the size of the particles and aggregates are also studied. The agreements of the temperature and major species are considered to be good between the predictions and the available measured date. When the fuel/air ratio equals to the stoichiometric ratio, the average temperature in the reactor reaches to the maximum. The results also indicate that the flame temperature field has a great influence on the size, size distribution and morphology of the final product. A flame of higher temperature more easily leads to spherical particles; the size of the particle aggregates becomes bigger with the long residence time. The data of simulation is confirmed with experimental result.

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. Numerical Simulation of Film Cooling in Turbine Cascade with Non-Axisymmetric Endwall Method,V231.3
  6. High Speed Aerodynamic Convection and Coupled Heat Transfer of Complicated Bodies,V215.4
  7. The Analysis on Characteris of Vibration Source about Vertical Vibration of Surrounding Environment Induced by Rail Transit,U211.3
  8. Study on the Heat Transfer Characteristics of Particle Cluster in Circulating Fluidized Bed,TK124
  9. Numerical Simulation of SNCR Process of a 600MW Utility Boiler,TK222
  10. Numerical Simulation of Biomass Direct Reburning,TK16
  11. Numerical Simulation on Pulverized Coal Combustion Process in a 670T/H Tangential Firing Furnace,TK224.11
  12. Numerical Simulation on the Combustion Process in the Furnace of a 1000MW Lignite-Fired USC Boiler,TK224.11
  13. Study on Gas-Solid Two-Phase Flow in Spouted Beds,TK173
  14. Experimental Study and Numerical Simulation on Aerodynamic Field of Tangential Bias Swirl Burner,TK223.23
  15. Characteristic Study of Combustion in Central Reverse Flame Chamber,TK223.21
  16. Numerical Simulation and Contrastive Analysis of Labyrinth Seals and Leaf Seals,TK263.2
  17. Preparation and Bioavailability Evaluation of Fenofibrate Nanosuspension,R944
  18. Electroporation Assisted Surface-enhanced Raman Spectroscopy for Living Cells,R318.51
  19. Numerical Study on Phosphorus Distribution in Water Environment of the Three Gorges Reservoir,X832
  20. Study on Hydraulic Fracturing of Low Permeability Reservoir,P618.13
  21. Adult OSAHS Preoperative and Postoperative Nasal and Pharynx Cavity and Soft Palate of the Numerical Analysis of Fluid-structure Interaction,R766

CLC: > Industrial Technology > Chemical Industry > General issues > Chemical machinery and apparatus, equipment > Chemical reaction process machinery and equipment
© 2012 www.DissertationTopic.Net  Mobile