Calibration of Discrete Element Parameters for Ganoderma lucidum Spore Powder and Performance Optimization of Gas-Collecting Hood

Abstract

The fine particle size of Ganoderma lucidum spore powder and the resulting low collection efficiency represent a prevalent challenge in the industry. To address this problem, a collection device for Ganoderma lucidum spore powder was designed in this study. The discrete element method and CFD-DEM coupling approach were adopted to conduct the contact parameter calibration of spore particles and the structural optimization of the gas collection hood. First, the factors significantly affecting the angle of repose were screened out via Plackett–Burman screening test and steepest ascent test, and a simplified regression model was established through the Box–Behnken experiment; the final parameter combination was then determined by EDEM verification, with a relative error of only 0.85% against the measured angle of repose. On this basis, the influence laws of side wall inclination angle, vertical height, and curved opening angle of the gas collection hood on flow-field characteristics and particle collection efficiency were analyzed. By comprehensively evaluating the three flow-field indicators (flow-field uniformity, effective negative pressure range, and vortex suppression), and using the collection efficiency as a verification indicator, the optimal structural parameter combination of the gas collection hood within the investigated ranges was determined as 50° side wall inclination angle, 90 mm vertical height, and 30° curved opening angle. The simulation results provide a reference for the structural design and parameter selection of the collection device.