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Coupled dissipative particle dynamics and discrete element method simulation on particle sedimentation under vibration toward functionally graded material fabrication

A novel solar roofing substrate material has been invented to use the functionally graded materials (FGMs) because of its unique thermal and mechanical properties. It has been successfully fabricated by sedimentation of different types of particles under vibration in the laboratory. To understand the physics behind the sedimentation process at multiple scales where some phenomenon cannot be captured by the continuum methods, previous numerical study has coupled the dissipative particle dynamics (DPD) and discrete element method (DEM) to study the size effect on particle sedimentation process without vibration, where the interactions between liquid-liquid and solid-liquid particles are described by DPD, while the solid-solid particles interaction is described by DEM. A parallel computing software, particle dynamics parallel simulator (PDPS), is also developed to use the DPD/DEM approach to simulate the sedimentation process. To further understand the vibration effect on the FGM fabrication, different approaches have been used to mimic the vibration effect from the vibration table in the laboratory. Results are compared and verified by the experimental data. The vibration magnitude, frequency and direction effects on the fabrication of graded microstructure have also been investigated and discussed in details. Results have demonstrated that the material gradation can be significantly amplified by vibration. The present DPD/DEM model provides a very useful tool for the material design and optimization of the solar roofing materials.

Author(s):

Lingqi Yang    
Columbia University
United States

Huiming Yin    
Columbia University
United States