基于Abaqus的耦合式玉米秸秆皮穰分离仿真与试验

Coupling Separation Simulation Analysis and Test of Corn Stalk Rind-pith Based on Abaqus

为提高玉米秸秆皮穰分离率、推进秸秆高值化利用进程,采用Abaqus/Explicit动力学显式求解器和中心差分求解法,对异向碾压和异向碾压锤切2种耦合式皮穰分离方法进行模拟分析,确定最佳耦合分离方式为异向碾压锤切耦合作用,进而试制秸秆异向碾压锤切皮穰分离试验台,并确定最佳工作与结构参数。以刀盘转速、碾压揭皮辊转速和刀片滑切角为试验因素,以秸秆皮穰分离率为试验指标,通过三元二次正交回归组合试验对分离试验台进行参数优化,利用Design-Expert进行数据分析,建立因素与指标间数学模型。试验表明:在刀盘转速为449 r/min、碾压揭皮辊转速为226 r/min、刀片滑切角为46°的最优工作参数组合下,皮穰分离率为88%,分离后的皮穰呈段状,满足实际生产需求。

Corn stalk is a kind of biomass resource that can be developed and utilized,with its comprehensive utilization can stabilize the balance of agricultural ecology and alleviate the pressure of energy and environment.In China,corn stalk is rich in yield and widely used.Because the mixed existence of rind and pith will affect its utilization effect,corn stalk rind-pith separation is an effective way to increase the use ratio of this biomass resource.Based on dynamic explicit solver of Abaqus in conjunction with central difference algorithm,both of rind-pith separation coupling modes differential directions rolling compaction and anisotropic pound-cutting with rolling compaction were simulated and analyzed to improve the rind-pith separation rate and promote the process of high value utilization of corn stalk.The simulation results showed that the breaking forms of the two separation modes were mainly tensile breaking and the breaking process was similar;differential directions rolling compaction method just made pith and rind de-bonding and did not realize separation of them,but anisotropic pound-cutting with rolling compaction can do it.Considering the practical application of the separated pith and rind of corn stalk,anisotropic pound-cutting with rolling compaction was selected as the best separation mode applying to corn stalk rind-pith separation test bench and used to determine the best working and structural parameters.Orthogonal regression combination test was used to optimize the working parameters of the test bench,taking cutting disks rotation speed,peeling rollers rotation speed and blade sliding angle as test factors,stalk rind-pith separation rate as test index and corn stalk of 1st~7th nodes as research object.After applying the variance analysis and the response surface analysis,regression models between factors and index was established by using the data processing software Design-Expert.Results showed that the cutting disks rotation speed,blade sliding angle the interaction between two previous factors,cutting disks rotation speed and peeling rollers rotation speed had significant effect on the stalk rind-pith separation rate;the significance sequence of influencing factors was blade sliding angle,cutting disks rotation speed and peeling rollers rotation speed.After optimizing the parameters of the model,it indicated that the maximum corn stalk rind-pith separation rate was 88%and segment length of corn stalk was 27 mm under the optimal working parameters combination of cutting disks rotation speed was 449 r/min,peeling rollers rotation speed was 226 r/min and blade sliding angle was 46°.The actual production demand was met and guidance for the design of corn stalk rind-pith separator was provided.