Kruszelnicka Weronika, Chen Zhengpu, Ambrose Kingsly
Department of Renewable Energy Sources Engineering and Technical Systems, Faculty of Mechanical Engineering, Bydgoszcz University of Science and Technology, Al. Prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland.
Agricultural and Biological Engineering, Purdue University, 610 Purdue Mall, West Lafayette, IN 47907, USA.
Materials (Basel). 2022 Dec 7;15(24):8729. doi: 10.3390/ma15248729.
Knowledge of physical and mechanical properties of cereal grains is important for designing handling and processing equipment. However, there is still a lack of knowledge on the influence of moisture content on the physical-mechanical properties as related to machine design. The aim of this study was to investigate and describe the changes in select physical-mechanical properties of maize, rice, and soybeans at various moisture content (10%, 14%, 18%, 22%, 26%; wet basis) and their compression behavior at two loading rates of 1.25 mm/min and 125 mm/min. The measured physical and mechanical properties include size, shape, and breakage force of single kernels. It was found that an increase in moisture content increased the kernel size, altered the kernel shape, and decreased the bulk density. The effects of moisture content and loading rate on breakage force, stress, and energy varied depending on the grain type. Our results indicated that an increase in moisture content changed the mechanical behavior of grain kernels from brittle to viscoelastic. To prevent kernel damage during processing and handling, the measured force and stress during compression can be used as the limit value for designing equipment.
了解谷物的物理和机械特性对于设计处理和加工设备很重要。然而，关于水分含量对与机器设计相关的物理机械特性的影响，仍然缺乏相关知识。本研究的目的是调查和描述玉米、水稻和大豆在不同水分含量（10%、14%、18%、22%、26%；湿基）下选定的物理机械特性变化，以及它们在1.25毫米/分钟和125毫米/分钟两种加载速率下的压缩行为。所测量的物理和机械特性包括单个籽粒的尺寸、形状和破碎力。结果发现，水分含量的增加会增大籽粒尺寸、改变籽粒形状并降低容重。水分含量和加载速率对破碎力、应力和能量的影响因谷物类型而异。我们的结果表明，水分含量的增加会使谷物籽粒的机械行为从脆性转变为粘弹性。为防止加工和处理过程中籽粒受损，压缩过程中测量的力和应力可作为设计设备的极限值。
