Design and structural optimization of acceleration pipe for MHD accelerated jujube air-suction harvester

The combination of magnetohydrodynamic (MHD) acceleration technology and the negative pressure suction principle ensures the effective lifting and transport of jujube fruits, addressing the challenges of traditional harvesting methods and providing a new solution for improving jujube harvesting efficiency. This study focuses on the impact of key parameters, including pipe diameter, electrode plate length, and electrode positioning, on the performance of the MHD acceleration pipe through numerical simulations. The structural optimization of the MHD acceleration pipe in the air-suction jujube harvester aims to enhance airflow acceleration efficiency. The results from both numerical simulations and experimental studies indicate that: 1) a smaller pipe diameter increases airflow velocity, while a larger diameter helps maintain the negative pressure environment inside the pipe and increases the pressure difference, 2) the length of the metal electrode plates contributes to improving the pressure difference, with longer plates generating larger pressure differences, and 3) proper electrode positioning is also crucial, as misalignment weakens the acceleration effect. Through orthogonal experimental design, the optimal configuration for the acceleration pipe was determined to be a pipe diameter of 160 mm, electrode plate length of 600 mm, and electrode position at 0 mm, resulting in an airflow velocity of 19.26 m/s and a pressure difference of 206.18 Pa. This study provides important theoretical insights for optimizing jujube harvesting equipment and demonstrates the potential of MHD acceleration control technology in agricultural machinery.