基于DEM-MBD仿真的滩涂贝类振动采收设备设计与试验

Design and Testing of Mudflat Shellfish Vibrating Harvester Based on DEM-MBD Simulation

摘要:

针对我国滩涂贝类机械化程度低、理论研究匮乏等问题，设计了一种履带式滩涂贝类筛-刷协同振动采收设备，设备采用双层振动筛-多级滚刷协同采收技术完成贝类挖掘、筛分、输送与分级等作业。以四角蛤蜊为研究对象，对双层振动筛与一级人字形双螺旋采收滚刷进行理论分析，推导其主要结构参数与运行参数范围。基于离散元法与多体动力学耦合仿真方法开展滩涂贝类振动采收仿真研究，确定设备关键结构参数：双层振动筛曲柄长度10 mm，一级人字形双螺旋采收滚刷螺旋升角30°。在辽宁省锦州市对样机开展滩涂贝类采收田间试验，以设备曲柄转速、一级人字形双螺旋采收滚刷转速、二级清理滚刷转速为试验因素，以贝类采收效率、破碎率与漏采率为试验指标完成滩涂贝类采收正交试验，求解设备运行参数最佳组合：曲柄转速为 870 r/min、一级人字形双螺旋采收滚刷转速为 65 r/min、二级清理滚刷转速为 110 r/min，贝类采收效率为133.80 kg/h、贝类破碎率为5.25%、贝类漏采率为7.46%。采收后50 mm深滩涂底质剪切强度降低65.13%，稚贝回滩率为92.29%，有利于贝类可持续化养殖。该设备满足滩涂贝类采收生产需求，为我国滩涂贝类机械化采收装备的设计提供了参考。

Abstract:

To address the challenges of low mechanization and limited theoretical research in shellfish harvesting on Chinese mudflats, a crawler mudflat shellfish mechanized brush-screen cooperative vibration harvester was designed for harvesting mudflats shellfish. This device integrated a double-deck vibrating screen and multi-stage roller brush system to efficiently excavate, screen，and transport shellfish. The white clam was used as the research object. The theoretical analysis of the double-deck vibrating screen and the first double-spiral harvesting roller brush were conducted and the key structural and operational parameters were then calculated. The mudflat shellfish harvesting single-factor test was conducted by using discrete element method （DEM） and multi-body dynamics （MBD） coupled simulations. The identified key structural parameters included a crank length of 10 mm for the double-deck vibrating screen and a spiral angle of 30° for the first double-spiral harvesting roller brush. The prototype was developed, and mudflat shellfish harvesting orthogonal field tests were conducted in Jinzhou City, Liaoning Province. The tests considered operational parameters such as crank rotation speed, the first double-spiral harvesting roller brush rotation speed, and secondary cleaning roller brush rotation speed. The optimal parameter combination was determined to be a crank rotation speed of 870 r/min, the first double-spiral harvesting roller brush rotation speed of 65 r/min, and secondary cleaning roller brush rotation speed of 110 r/min. Under these conditions, the device achieved a clam harvesting efficiency of 133.80 kg/h, a clam breakage rate of 5.25%, and a clam missing rate of 7.46%. Post-harvest, the shear strength of the mudflat at a depth of 50 mm was decreased by 65.13%, and the juvenile clam return rate was 92.29%, supporting the sustainable cultivation of shellfish. This device met the production requirements for mudflat shellfish harvesting and it can serve as a valuable reference for the mechanization of shellfish harvesting in China.