The 7th National Conference on Computational Mechanics of Granular Materials in conjunction with The 4th International Symposium on Computational Particle Technology (CMGM-2024 & CPT-2024)

In this paper, the bidirectional coupling numerical simulation method of computational fluid dynamics (CFD) and discrete element method (DEM) is used to explore the dynamic characteristics of wet particles in the conveying process. The correctness of the numerical model and the independence of the grid are verified by the comparison and analysis of the particle velocity on the center line outside the elbow. Firstly, the transportation process of thin phase wet particle pneumatic transportation was simulated, and the effects of different particle moisture content, gas velocity and particle size on thin phase transportation were discussed. The changes of particle dynamics characteristics, solid concentration, transportation efficiency, pipeline pressure drop and wet particle agglomeration characteristics were studied. Then, on the basis of thin phase transportation, the solid phase flow characteristics and mechanism of dense phase wet particle pneumatic transportation under different transportation conditions are analyzed. It is found that the optimal economic velocity of wet particle transportation under different gas velocities is 9m/s, and wet particles are more likely to form slug flow under the action of liquid bridge force than dry particles. In addition, combined with the actual situation of pneumatic conveying, this paper studies the pneumatic conveying of non-spherical wet particles, uses the vertical-bent-horizontal pipe to deeply explore the influence of sphericity, particle moisture content and gas velocity on pneumatic conveying, evaluates the efficiency of conveying system and the wear of the bend, and more accurately understands the behavior law of wet particles during conveying. It provides more scientific guidance for system design and optimization, and promotes the further development and application of pneumatic conveying technology.