关键词: 干法制粉;混料过程;挡板数目;CFD方法

Abstract: In order to study the influence of the number of baffles at the bottom of the granulation chamber on the mixing process of dry powder , the Euler Euler gas solid two phase flow mathematical control equation was constructed , and the physical model of different baffle number was established .The modified RNG k-ε model was used to simulate the turbulent flow in granulation chamber .Numerical simulation of flow field in granulation chamber for ceramic dry powder with different number of baffles was carried out.Analyzing the different baffle number of granulation chamber particle volume distribution , velocity field, turbulent kinetic energy, turbulent kinetic energy dissipation , and the simulated results were compared with the experimental results .The results show that: the number of baffle plates have a certain impact on the mixing process, the appropriate number of baffle plates can improve the distribution of volume distribution, improve the speed of synthesis of particles , have better turbulent kinetic energy and turbulent kinetic energy dissipation , is conducive to the promotion of particle mixing ; the distribution of flow field in the prilling chamber with baffles is better than that without baffle , when the number of baffles increases, the granulation effect increases first and then decreases with the increase of baffle number; when the number of baffles is 4, the particle size distribution is 72％, the accumulation phenomenon is greatly improved, the speed is better, the turbulence energy dissipation is improved , and it is beneficial to the effective mixing of the fluid medium in the granulation chamber ; when the number of baffles is 0, 2, 4 and 6, the qualified rate of particles is 82％, 84％, 90％ and 85％, respectively, the fine particles between 30-60 mesh accounted for 58％, 62％, 71％ and 64％ respectively; the experimental results verify the accuracy of the numerical simulation , and provide some theoretical guidance for the structural optimization and design of the rotary flow granulator .

Key words: dry powder;mixing process;baffle number;Computational Fluid Dynamics method