| The conception of Impinging Streams (IS) was first put forward by a famous Russian scientist - Elperin in 1961. Then the IS study of two phase flow lasted for more than ten years about experiment and its application. Following his study, Tamir and Wu Yuan carried out the study of mass transfer enhancement and application at drying, absorbing, air and solid cooling, fast heating, mixing and multiphase reacting process with IS. The research results confirm that IS can not only enhance heat and mass transfer process, but also promote the process of the chemical reaction. Wu Yuan points out that the flue gas cleaning of coal may be a very suitable object for IS technique.In recent years, a lot of papers about the application experiment research and 2-D numerical simulations were published concerning the characteristics of effective heat and mass transfer with IS reactor. However, 3-D numerical simulations for IS characteristics are quite few by using FLUENT software. Because adopting the method of experiment research will bring the enormous investment and physically the IS is of 3-D, So this paper puts forward the 3-D numerical simulation to investigate the characteristics of flow field and particle moving of IS using the software of FLUENT. The 3-D numerical simulation would provide an actual flow regulation and more accurately computing data. The useful fundamental data and theory basis will be helpful for the design and development of an IS flue gas purifying device of coal.Through establishing a geometrical model of IS absorber, dividing mesh, choosing proper mathematics model and iterating computation, this paper firstly studied the flow characteristics of air phase. The velocity and static pressure distribution of the fluid were studied and then the main factors (velocity in-let and acceleration tube distance) affecting the maximal radial speed were discussed. Secondly, this paper studied the moving characteristics of iron particles, including the particle tracks, axial velocity, concentration distribution and the average residence time. The main factors (velocity in-let, particle diameter and acceleration tube distance) affecting the average residence time were also discussed.By comparison with the results from the experiment, it is found that the numerical simulation method can succeed in simulating the IS absorber. Then we can draw the conclusion that the model is suitable and it is applicable to use the 3-D numerical simulation to carry out the research of Impinging Streams. The results of the 3-D numerical simulation provided basic data and theoretical bases for the further optimized and improved design of Impinging-Streams absorber, and that will finally be benefit in obtaining a new magnetic-desulphurizaion technology of Impinging-Streams with high efficiency, low cost and independent intelligent property right.
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