| Bench coating laver is one of the most economical cultured laver in China.The harvesting and transportation of laver is the most important link in the production chain of laver.Compared with developed countries,the overall level of laver harvesting equipment in China is still relatively low,with high labor intensity,low production efficiency and high loss rate.Much of the post-harvest transportation of laver is also entirely manual.According to the technical requirements of collecting and transporting equipment and the biomechanical characteristics of striped laver,the optimal design of cutting tool,conveyor line and inlet of laver was carried out.The optimal parameters of corrugated knife and helical line were determined by response surface analysis.Bench comparison test and offshore verification test were completed,and the specific studies are as follows:This paper analyzed the existing problems of laver harvesting and transportation equipment,and determines the optimization scheme of corrugatedknife,spiral tube and low inlet structure of harvesting equipment.Based on the experimental results of biomechanical properties of laver,the shear and tensile simulation of Lazuli striped by finite element method(FEM)was carried out.The results showed that when the contact keyword was Contains aggressive contact,the Poisson ratio was 0.36 and the friction coefficient was0.51,The measured and simulated values of laver have the smallest error The result showed that the simulation model of laver was of high usability,which lay a foundation for the simulation of laver harvesting equipment.Based on ANSYS/LS-DYNA,a rigid and flexible coupling model of the interaction between corrugated knife and laver was designed.The influence of the main structural parameters of corrugated knife on the axial,radial and tangential forces of laver was investigated by orthogonal experiments on the response surface,and the optimal structural parameter combination of corrugated knife was determined as follows: The slip Angle was 21°,the cutter Angle was 106°,and the curved edge Angle was 15°,Compared with the straight knife harvesting equipment,the cutting force of nori was increased by 45.26%,and the tensile force was reduced by 68.35%compared with the straight knife harvesting equipment.The results showed that the loss rate of the optimized corrugated tool was reduced to 52.98% and the net rate was increased to 98.75%.The results of the sea trial showed a loss rate of 2.28 per cent and a net recovery rate of 96.34 per cent.Through the corrugated knife,the key technology of low-loss harvesting of slip cutting cutting is broken.An optimization model of low inlet and helical tube for conveyance equipment was designed.The flow path of laver was analyzed by two-phase flow simulation of the spiral tube.The velocity cloud of the key plane was set up to show that the flow through the spiral tube into the bend will have shear effect,which is helpful to relieve the block of the bend.Based on orthogonal test of response surface,the influence of main structural parameters of helical tube on the swirl ratio of two-phase flow is studied.The optimum combination of helical angle was 61°,helical length was150 mm,bending distance was 105 mm,and the rotation velocity ratio was 47.38%.The results of platform comparison showed that the transmission efficiency of spiral tube conveyor was 1.79 times higher than that of direct tube conveyer,and the loss rate was 47.9% lower.The sea trial showed that spiral low inlet conveyor can transport laver effectively and solve the key problem of clogging of conveyer.Through the key technology of swirl conveying,the problem of blockage of the conveying pipeline was solved. |
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