不同成熟度莲籽力学特性试验

以产自湖北洪湖的太空莲36号莲籽为研究对象，测定不同成熟度莲籽外形尺寸和含水率，并进行力学特性试验。结果显示：乳熟期、蜡熟期、完熟期莲籽纵横径比平均值分别为1.35、1.28、1.19，含水率分别为79.84%、70.28%、57.72%，莲籽长轴弹性模量分别为1.09、1.22、1.85 MPa，短轴弹性模量分别为1.33、1.42、2.16 MPa；3种不同成熟度莲籽极限破坏载荷分别为81.995、117.107、167.640 N。研究结果表明，莲籽同一成熟度和剪切深度条件下，剪切力不随剪切速率改变；莲籽同一成熟度和剪切速率条件下，剪切力与剪切深度呈显著线性相关；莲籽在X、Y、Z轴方向上的压缩破壳力随着成熟度的增加而增加；相同成熟度下，莲籽三轴方向上的压缩力在数值上X轴

Mechanical properties of lotus seeds with different maturity

Lotus seeds with different maturity have different mechanical properties. At present,shelling machinery is only suitable for lotus seeds after ripening stage. However,the crushing rate increases greatly when milk and wax ripening stages of lotus seeds are shelled. In order to improve the applicability of shelling machinery and reduce the crushing rate of fresh lotus seeds in the process of shelling and peeling,the compression,crushing and shearing characteristics of lotus seeds with different maturity were studied. In this study,the lotus seeds of space lotus No. 36 from Honghu Lake,Hubei Province were used to measure the shape dimensions and water content. The long-axis and short-axis compression and the crush test for whole lotus seed were conducted. The shear test under different speeds and depths,and the compression test in three-axis direction were carried out. The elastic modulus of lotus shell was tested. The long axis and short axis elastic modulus were analyzed and calculated based on experiments above. The ultimate failure load,the relationship between shear stress and depth,speed and maturity were obtained. The results showed that the average longitudinal and transverse ratio of the lotus seeds with milk maturity,wax maturity and maturity was 1.35,1.28,1.19,respectively. The water content was 79.84%,70.28%,57.72%,respectively. The long axis elastic moduli of lotus seeds were 1.09 MPa,1.22 MPa,and 1.85 MPa,respectively. The short axis elastic moduli were 1.33 MPa,1.42 MPa,and 2.16 MPa,respectively. The limit damage load of three maturity lotus seeds was 81.995 N,117.107 N,and 167.640 N,respectively. Under the same maturity and shear depth,the shear force did not change with shear speed and was linearly correlated with shear depth. The compression shelling force of lotus seed in the X,Y and Z directions increases with maturity. The compressive force in the three-axis direction of the lotus seed is numerically X axis