摘要
棉秆力学特性是研究棉秆收获机械的理论基础。为此,通过采集不同时期的棉秆,测定力学性能和物理性能;通过典型相关性分析,研究棉秆的物理性能与力学特性的关系;采用线性回归模型分析棉秆起拔力、土壤紧实度、棉秆直径及棉秆含水率的关系,对模型进行优化并建立棉秆的起拔力模型。试验结果表明:抗拉强度在含水率最高为61%时达到最大值37.65MPa,当含水率在在15%~50%之间,棉秆的抗拉强度变化不大,平均抗拉强度集中在21.5~25.8MPa之间;对于抗弯强度,在含水率在为15%时达到最高值33MPa,当含水率在25%~55%之间,棉秆的抗弯强度变化不大,平均抗弯强度集中在23.5~27MPa之间;对于棉秆起拔力,在土壤紧实度为最低的3.3kg/cm时达到最小值340.7N,棉秆的起拔力随着土壤紧实度的降低而减小。通过典型相关性分析可知:棉秆的弯曲破坏载荷及拉伸破坏载荷与棉秆的直径和棉秆的含水率都有着显著的相关性,且棉秆直径对弯曲和拉伸破坏载荷的影响远大于含水率对棉秆拉伸和弯曲破坏载荷的影响;含水率与棉秆的抗拉强度呈正相关,与抗弯强度呈负相关。对棉秆的起拔力与棉秆含水率、棉秆直径及土壤紧实度进行多元回归分析,得到棉秆起拔力与棉秆直径以及土壤紧实度的模型为y=-111.73707+45.39254x1+23.89125x2,其拟合优度为0.81,可用于对棉秆起拔力的预测和拔棉秆机的设计研究。该研究对于推进棉秆机械化回收发展具有重要的指导意义。
The relationship between the physical and mechanical properties of cotton stalk was analyzed by the typical correlation analysis,and the linear regression model was used to analyze relationship among the pulling force of the cotton stalk,soil density,diameter of cotton stalk and percentage of moisture in the cotton stalk,improving the model and obtaining the pulling force model.Result showed that:For the tensile strength,when the rate of water content reaches 61%,the highest tensile strength can be obtained,which is 37.65 MPa;when the rate is various in 15%-50%,the tensile strength dosen’t change a lot,with average strength changing from 21.5 MPa to 25.8 MPa;for the bending strength,the highest bending strength(33 MPa)can be obtained when the rate of water content reaches 15%.When the rate is among in 25%~55%,the strength dosen’t change a lot,with the average strength being in 23.5-27 MPa;for the pulling force,when the soil density reaches the lowest point,which is 3.3 kg/cm2,the pilling force can be 340.7 N as the lowest,the pulling force of cotton stalk decreases with the decrease of soil density.Through the analysis of typical correlation,it can be concluded that the bending failure load and tensile failure load of cotton stalk have obvious correlation with the diameter of cotton stalk and moisture content of cotton stalk.Even the influence of cotton stalk diameter on the bending and tensile failure load is much greater than that of moisture content on the tensile and bending failure load of cotton stalk.Percentage of moisture is positively correlated with tensile strength of cotton stalk and negatively correlated with bending strength.Performed the regression analysis for pulling force,water content of cotton stalk,diameter of cotton stalk and soil density,and the result showed that the relationship between pulling force and water content of cotton stalk was not obvious.The pulling force of cotton stalk was positively correlated with soil density and diameter of cotton stalk.Because the simple regression
作者
汪珽珏
陈明江
张佳喜
王振伟
赵维松
曲浩丽
Wang Tingjue;Chen Mingjiang;Zhang Jiaxi;Wang Zhenwei;Zhao Weisong;Qu Haoli(School of Mechanical and Electrical Engineering,Xinjiang Agricultural University,Urumqi 830052,China;Nanjing Research Institude for Agricultural Mechanization,Ministry of Agriculture,Nanjing 210014,China)
出处
《农机化研究》
北大核心
2020年第4期132-138,共7页
Journal of Agricultural Mechanization Research
基金
国家自然科学基金项目(51505242,51865058)
中国农业科学院基本科研业务费项目(Y2017PT23)
新疆科技支疆项目(2018E02082)
关键词
棉花拔秆
力学特性
典型相关性分析
多元回归
cotton pulling
mechanical properties
typical correlation analysis
multiple regression
