自走式全混合日粮制备机取料装置设计与试验

Design and Experiment of Loading Elevator of Self-propelled TMR Preparation Mixer

针对自走式全混合日粮制备机缺乏取料机理、堵塞问题明显的情况,建立了取料作业的理论模型,对取料宽度、刀具回转半径、取料刀安装螺距、取料刀密度、取料转速、每刃进给量、抛料速度、物料射入角和输送带尺寸等关键因素进行了设计与计算。为衡量取料刀刃口长度与取料宽度之间的关系,提出取料刃长度比C的概念,取C为1.25。采用EDEM对青贮取料进给速度和取料转速等关键因素进行了仿真,分析表明由于螺旋叶片与护罩间隙较大,物料会随着取料刀和滚筒高速转动,回流率较高。提高取料进给速度,取料效率增大,但回流率上升。当进给速度为4 m/min时,回流率高达50.05%,造成物料的过度切割,且能耗大。增加取料转速,取料效率增大,回流率降低,但转速超过230 r/min后驱动扭矩增幅较大。采取中等进给速度和取料转速,加大取料刀安装螺距、滚筒护罩后部导流倾角和物料射入角,能够提高取料效率,并降低回流率和能耗。选取料进给速度2.5 m/min和转速230 r/min对优化装置进行仿真和试验,结果基本一致。仿真分析功耗降低64%,试验未出现堵塞和憋车现象,取料宽度2000 mm,取料高度5050 mm,取料效率75.02 m^(3)/h,回流率28.95%。

Due to the lack of research on loading mechanism,preventing blockage,and optimization methods for self-propelled TMR preparation mixer,a theoretical model of loading operations was established.The key factors,such as reclaiming width,rotation radius of cutter,installation pitch of cutter,distribution of cutter,rotation speed of feeding drum,feed rate of each blade,material ejection speed,incident angle of particle and size of the conveyor belt were designed and calculated.In order to measure the relationship between the cutting edge length of blade and the reclaiming width,a concept of the length ratio of cutting edge C was proposed,and C was taken as 1.25.EDEM was used to simulate the key factors such as the feed speed and the rotation speed to reclaim silage.The analysis showed that due to the large gap between the spiral blade and the shield,the material was rotated at a high speed with the cutter and the drum,and the reflux ratio was high.With the increase of feed speed,the reclaiming efficiency was increased,but the reflux ratio was increased at the same time.When the feed speed was 4 m/min,the reflux ratio was up to 50.05%,which would cause excessive cutting of silage and large energy consumption.With the increase of rotation speed,the efficiency was increased and the reflux ratio was decreased,but the driving torque was increased greatly when the rotation speed exceeded 230 r/min.Therefore,a medium feed speed and rotation speed should be adopted.By increasing the installation pitch of cutter,the diversion angle of the back of drum shield and the incident angle of the particle,the reclaiming efficiency can be improved and the reflux rate can be reduced.When the feed speed was 2.5 m/min,the rotation speed was 230 r/min,conclusions of simulation and experiment of the optimized device were basically the same.Simulation analysis showed that the power consumption was reduced by 64%,no blockage and engine stalling occurred during the test.The reclaiming width was 2000 mm,the reclaiming height was 5050 mm,the reclaiming efficiency was 75.02 m^(3)/h,and the reflux rate was 28.95%.