| The behaviors of gas stream and solid discrete phase had been studied bynumerical simulation and experimental method. The commercial CFD softwareFLUENT6.2 was used to simulate the flow field in inertia elutriators. The velocityand static pressure distributions of gas phase were obtained, which had been used toanalyze structure factors affecting classification efficiency in order to restructure andimprove the performance of the equipment. Based on the numerical simulation results,high efficiency BIE elutriator equipment was developed. The main works of this studyincludes:1. The influence of each force act on particles in inertia elutriator was analyzed.For gas stream, Reynolds-averaged model based on Euler method was used and k-εmodel was applied to form algebraic finite volume equations. For solid phase,discrete phase model based on Lagrange method was used considering couplingbetween gas and solid phase, in which interaction between particles and gas, as wellas interaction between particles and wall were considered.2. The physical model of inertia elutriator was established and meshed inGAMBIT2.2. A new method that generated the grid through reasonable cutting theflow field region was put forward. The standard k-εmodel provided by FLUENT6.2was selected to simulate flow field in UGS and BIE. To meet the rebuilt request ofeach part of UGS elutriator, five projects were designed, simulated and analyzed,which provide new thoughts to develop new type elutriator. BIE elutriator wasdesigned, based on the result of simulation and experiment study. It is found that:short circuit and bad vortex in the top of convection sect were eliminated, disturbbetween mutual flow was avoided through connecting inner canister of accelerate andexpand section; share stress and stay time of particles was increased in the newelutriator. Flow field became more symmetry as gas inlet was lowered and two layersof jalousie was added. It is found that jalousie had a distinctness effect on flow field. 3. Based on flow field simulation, moving behavior of particles in the two inertiaelutriator was simulated with discrete phase model, which predicted tracks of particlesof different sizes. Equipment structure influence on particle was found throughanalyzing particle velocity distribution. The particular inner parts in BIE elutriatormade the particle movement more controllable. Separate performance in threeoperation condition was token by classification efficiency based on particle tracingmethod. The compared result showed that classification efficiency for polyethyleneparticles in BIE is 30 percent higher than in UGS.4. Using the IFA-300 and U-mould pressure meter, the flow field and staticpressure distribution had been measured in different section of BIE elutriator. Thecomparison of the experiment data and the simulation result showed that simulation isreliable, experiment is carried out using industry product polyethylene and theseparation ability of UGS and BIE is tested. The consistent experiment and simulationresult showed that it is reasonable to calculate separation efficiency with particletracing method. Best operation condition is found after repetitious experiments, inwhich integrate separation efficiency is 28% higher than UGS's.
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