西北旱区马铃薯压缩力学特性研究

Study on the compressive mechanical properties of potato in arid areas in Northwest China

为获得马铃薯的弹性模量E、泊松比μ、剪切模量G等力学参数,分析西北旱区马铃薯压缩力学特性。对含水率为80.06%左右的马铃薯,在5种不同加载速率(2mm/min,3mm/min,4mm/min,5mm/min,6mm/min)和不同加载方向下(x方向:马铃薯整茎中心的脐部与整茎顶点的连线方向;y方向:马铃薯块茎径向截面的短轴方向;z方向:马铃薯块茎径向截面的长轴方向)进行压缩试验。得到马铃薯圆柱体试验样体的弹性模量、泊松比和剪切模量的平均值分别为E=4.188MPa,μ=0.569,G=1.336。将其作为此品种马铃薯(产自甘肃定西)的弹性模量和泊松比。分析结果表明:加载方向对马铃薯破裂影响显著,加载速率对马铃薯破裂有极为显著的影响:当马铃薯整薯试验样品的加载速率一定时,在不同加载方向下马铃薯的加载力—时间曲线不相同,但大致表现为其x方向加载力—时间曲线高于y方向,y方向高于z方向;在加载速率为2mm/min,4mm/min时,破裂力表现为z向>x向,x向>y向;加载速率为3mm/min,5mm/min时,x方向加载力—时间曲线高于y方向,y方向高于z方向。本研究为西北干旱地区马铃薯的采收到加工的各个环节所涉及的机械设备的设计与制造提供不可或缺的机械参数。

To obtain the modulus of elasticity E,Poisson＇s ratioμ,shear modulus Gand other mechanical parameters analysis of compressive mechanical properties of potato in arid area in Northwest China.Measured water content is about 80.06% of potatoes,5 different loading rate（2 mm/min,3 mm/min,4 mm/min,5 mm/min,6 mm/min）,and under different loading directions（x-direction;Potato tubers of the umbilicus with vertex connection direction;y-direction：tuber radial short axis of the section;z-direction：radial cross section along the long axis of the tuber）compression tests.Get potato elastic modulus,Poisson＇s ratio and shear modulus respectively E=4.188 MPaμ=0.569,G=1.336.It as the varieties of potatoes（made in Dingxi city,Gansu province）modulus of elasticity and Poisson＇s ratio.Analysis results showed that loading directions on the potato burst significantly,loading rate on rupture of the potato had a very significant effect：when test samples of the whole potato loading rate is constant,the potato under different loading directions of load-time curve is not the same but for the xdirection load-time curve is higher than y,ydirection than the zdirection;in the loading rates for 2 mm/min,4 mm/min,cracking for zx,xy;loading rate for 3 mm/min,5 mm/min,load-time curve was higher than ydirection in xdirection and ydirection than the z direction.This research in arid areas in Northwest China potato harvest,storage,conveying and processing equipment provide the necessary mechanical design of parameter.