Study on Arch Evolution Behavior of Discharging Biomass Particles from the Aerated Hopper

Biomass particles with low density and pronounced anisotropy tend to form periodic dynamic arches during hopper discharge, which severely affects flow stability and controllability and has become a critical bottleneck restricting their large-scale and efficient utilization. In this study, the complete evolution of dynamic arches of corn stover and corn cob was revealed with the help of high-speed image processing and signal analysis techniques. The results reveal a clear transition from long-period intermittent arching to short-period rapid arch collapse and finally to arch-free stable flow with increasing gas velocity. By conducting force analysis on arch formation and collapse processes, it clarifies the intrinsic driving mechanism of the periodic arch-collapse behavior of biomass particles, where the periodic alternating evolution of pressure difference directly dominates the arch structure. Based on this, a semi-empirical model integrating gas seepage and arch dynamics was established to calculate the arch period, and the model-calculated values are in good agreement with the experimental results. This study conducts an in-depth analysis of the arch-breaking mechanism of corn stover and corn cob in a conical hopper under aeration conditions. The results can provide a reference for the aeration optimization of biomass feeding systems with similar material characteristics and hopper configurations.