基于离散元的烟丝输送模拟与管道优化研究OA

[Objective]To improve the accuracy and reliability of the discrete element method in optimizing the design of tobacco shred conveying elbows,an X-Y-Z three-dimensional irregular breakage model was established.Based on this,a gas-solid coupling method(CFD-DEM)was employed to optimize the elbow structure design.[Methods]Taking Hongshuangxi(Hard)tobacco shreds from a cigarette factory as the research object,the key parameters for the breakage model were measured through methods such as the heavy-ball drop test.With the pipe bending angle,bending radius,and inlet-outlet length ratio as critical experimental factors,and the pipeline wear condition and the remaining Bond key ratio of tobacco shred particles as experimental indicators,the influence of each factor on tobacco shred conveying costs was analyzed.[Results]The total pipeline wear decreased with increases in both the bending angle and bending radius.The degree of pipeline wear for different inlet-outlet length ratios followed the order:1∶1.5<1∶1<1.5∶1.The remaining Bond key ratio of tobacco shred particles increased with the increase of the bending angle;it first decreased and then increased with the increase of the bending radius;and the degree of tobacco shred breakage for different inlet-outlet length ratios followed the order:1∶1.5<1∶1<1.5∶1.The orthogonal experiments revealed that the order of the factors affecting tobacco shred quality were:the inlet-outlet length ratio,bending radius,and bending angle.The optimal factor combination for the pipeline was a bending angle of 150°,a bending radius of 1 500 mm,and an inlet-outlet length ratio of 1∶1.5.Under this condition,the simulated breakage rate for 10 g of tobacco shred particles during conveying was 1.505%.The verification test of the breakage rate of this optimal combination yielded an actual breakage rate of 1.333%,with a relative error of 0.172%.Compared with the actual breakage rate under general operating conditions for elbow conveying,it was reduced by 3.074%approximately,effectively lowering the cigarette conveying costs.[Conclusion]The optimized elbow structure reduces the breakage of tobacco shreds after pneumatic conveying.The research findings can provide a theoretical basis for the rational layout of pipelines and the optimized design of elbows.