Abstract: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 poundcutting 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 27mm under the optimal working parameters combination of cutting disks rotation speed was 449r/min,peeling rollers rotation speed was 226r/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.
