Multi-level arch characteristics and flow enhancement regulation of nano powders discharged from silo

Abstract

Nanoparticles have broad application prospects, but their poor flowability poses a challenge to the handling and transportation. Here, we experimentally demonstrate that modulated pulsed aeration can destroy the consolidation of nano powder and achieve a breakthrough in silo discharge from clogging to flow. We confirm the multi-level arch structure in the silo discharge of nano powders: free-fall arch and cohesive arch. And the location of multi-level arch can be determined by the yield stress of material. Furthermore, the method of combined pulsed aeration was proposed to enhance the discharge flow. Specifically, the influence of modulation of pulsed airflow including frequency and duty cycle and aeration location configuration on nanoparticles silo discharge flow was explored. And the optimal combination method of double pulsed aeration was determined to eliminate the cohesive arch and greatly increase the discharge rate, which is close to the hypothesis liquid-like flow rate.