Characterization of green pepper distribution on a spiral curved surface

Green pepper (Zanthoxylum armatum) has significant culinary value, but its high separation costs limits industry development. This study developed a cost-effective method for separating green pepper particles using a spiral curved surface, demonstrating significant economic advantages compared to manual and color sorting approaches. Through dynamic analysis, Discrete Element Method (DEM) simulations, and laboratory experiments, the distribution of particles along the spiral surface was studied. Results indicated that feeding velocity, position, helix angle, and radial inclination are key factors affecting particle movement. An equilibrium velocity model was developed to determine the feeding velocity, while an action mechanism model was used to examine the impact of these factors on separation efficiency. The optimal separation parameters were identified and experimentally validated as a helix angle ($\alpha$) of 60°, a radial inclination angle ($\beta$) of 20°, and a feeding radius ($r$) of 70 mm. The findings of this investigation, may provide a theoretical basis for the creation of low-cost separation technologies and equipment prototypes for granular materials, particularly green pepper, with potential benefits for global food safety.