【摘要】 为解决玉米籽粒收获机卸粮装置卸粮速度低与籽粒破碎率高的问题，本研究基于EDEM离散元法对卸粮装置的结构参数进行优化。采用动力学方法分析玉米籽粒在卸粮过程中的运动轨迹及各个输送阶段的速度和受力变化情况，得到搅龙螺距组合、搅龙转速组合、进料口开度等关键参数变化范围。试验采用Design-Expert软件进行Box-Behnken试验设计，以卸粮速度和籽粒未破碎率的加权综合指标评分值为核心评价指标，进行3因素3水平仿真试验优化求解。根据试验结果建立了加权综合指标评分值与显著性参数的二阶回归模型并对其进行优化。结果表明:底搅龙螺距270 mm、竖直搅龙螺距340 mm、水平搅龙螺距300 mm;底搅龙转速573 r/min、竖直搅龙转速与水平搅龙转速均为650 r/min;进料口开度120 mm时卸粮速度111 L/s，籽粒破碎率0.36%，最后根据最优组合参数进行田间验证试验，测得卸粮速度为106.379 L/s，与仿真结果值111 L/s对比误差为4.3%;破碎率为0.73%，与仿真结果值0.36%对比相差0.37%。结果表明该卸粮装置的参数匹配设计合理，可为玉米籽粒收获机卸粮装置的参数优化工作提供实践参考依据。更多还原

【Abstract】 To address the issues of low unloading speed and high kernel breakage rate in the grain unloading device of corn grain harvesters,this study optimized the structural parameters of the unloading device based on the EDEM discrete element method. Using dynamic methods,the motion trajectory of corn kernels during the unloading process,as well as the changes in speed and force across various conveying stages,were analyzed to determine the variation ranges of key parameters,including auger pitch combinations,auger speed combinations,and feed inlet opening. The experiment employed Box-Behnken design via Design-Expert software,with the weighted comprehensive index score of unloading speed and unbroken kernel rate as the core evaluation criteria. A three-factor,three-level simulation test was conducted for optimization. Based on the experimental results,a second-order regression model relating the weighted comprehensive index score to significant parameters was established and optimized. The findings indicate that the optimal parameters are as follows: bottom auger pitch of 270 mm,vertical auger pitch of 340 mm,and horizontal auger pitch of 300 mm; bottom auger speed of 573 r/min,vertical and horizontal auger speeds of 650 r/min each; and a feed inlet opening of 120 mm. Under these conditions,the unloading speed reaches111 L/s,and the breakage rate is 0. 36. The optimal combination test results indicate: the unloading rate is 106. 379 L/s,with a 4. 3% deviation compared to the simulated value of 111 L/s. The breakage rate is 0. 73%,differing by 0. 37% from the simulated value of 0. 36%. The results demonstrate that the parameter matching design of this unloading device is reasonable,providing a practical reference for optimizing the parameters of grain unloading devices in corn grain harvesters.更多还原