| With the development of industrial technology and demand of environmental protection, it is necessary to separate industrial dust. Not only does industrial dust endanger human health, but destroy industrial equipments, and jeopardize the security of apparatus operation. In these circumstances, the inertial particle separation equipment—furcated duct will be explored in this paper, which has an advantage of no moving element and low pressure loss.It is very difficult to carry out experimental research and numerical simulation in the furcated duct because of the extremely complicated gas-solid turbulent flow. In this thesis, the high-speed photography technology can be used to get particle trajectory combined with image processing technology. The particle velocity can be measured by locating particles position in the particle trajectory images, which are processed with overlapping images technology. It can be concluded that the separation efficiency of particle is related to particle physical nature, structure and material of furcated duct, inlet air velocity and the velocity of particles and so on, the separation efficiency of lump corns is better than ball millets, which have the same density with corns, and with the increase of inlet velocity, all particles'separation efficiency will be raised gradually. This is becauseOn the basis of analyzing ball particle force balance and particle-wall impact model, gas-solid separation phenomenon is investigated by using standard k-εturbulent model and discrete phase model (DPS). Also, the total pressure loss and particle separation efficiency are explored on different flow matching of three conditions. It can be demonstrated that the total pressure loss efficiency will increase rapidly when the inlet velocity of air is raised, and the pressure loss efficiency of clear-up flow passage will decrease more vastly than of the main flow passage with the increase of clear-up flow rate factor in the same inlet velocity of air. On the condition of small SCR, the back flow phenomenon can be observed in the scavenge duct, and the back flow domain will become small with the increase of SCR. In the aspect of particle separation, its efficiency will increase when the loaded particle velocity decrease. To particles with a diameter over 100μm, the separation efficiency has a maximum value nearθ=15°, whereθis defined as the velocity direction of loaded particles.(1) From the comparison of particle trajectories between experimental results and numerical simulation results, the difference is rather big, especially when particles rebounding from the boundary, due to ignoring the influence of FM and FB. Also, the phenomenon is neglected that some particles will slide along the boundary as result of week friction factor. So, the boundary condition law of DPM should be made better.(2) It is suggested that there be some need to improve the structure of furcated duct in order to enhance separation efficiency and weaken the pressure loss. The structure change includes lengthening the shrinkage part and shortening cross-section part of the furcated duct, which can improve particles inertia force in the direction of the main flow to separate them effectively. It is also a good way to separate particles installing pre-rotation vane. In a word, the structure change avoids wide-angle particle impact on the boundary to separate particles with advantage.(3) The image method is achieved in the particle size analysis. Analyze experiment inaccuracy and make some suggestions.
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