Design and Experimental Evaluation of a Spiral Feeding Device Based on Friction Characteristics of Wheat Straw

The aims of this study were to achieve working stability and continuity of the straw fibre extruder(D200)to improve the transportation efficiency of pretreated straw materials mulch film.Based on a theoretical analysis of wheat straw friction characteristics and the mechanics model of wheat straw transport,a tilting variable-diameter spiral feeding device matched the designed straw fibre extruder(D200-type).Experimental researches were performed by using the orthogonal test method of the L16(45)to obtain the optimal parameter combination.The spiral angle,the speed of the screw shaft and the moisture content of straw raw materials were selected as influencing factors,and feeding efficiency was selected as the objective indicator.The results showed that the spiral angle,the rotating speed of screw shaft and the moisture content of straw raw materials had very significant effects on the feeding efficiency(p<0.01).The order of the extent of the influence of parameters on the feeding efficiency of wheat straw raw materials from high to low was the moisture content,the spiral angle and the speed of screw shaft.When the maximum transfer efficiency per unit time of the inclined spiral feeding device was 1040.8 kg·h-1,the spiral angle was 40?,the speed of screw shaft was 200 r·min-1 and the moisture content was 65%.Verification experiment proved the feasibility of straw fibre extruder designed.

Multi-objective optimization design of wheat centralized seed feeding device based on particle swarm optimization (PSO) algorithm

In order to solve the problem of interaction between multiple evaluation indexes of seed metering performance under multiple factors of centralized seed feeding device,a multi-objective optimization of structure based on particle swarm optimization(PSO)algorithm was proposed in this paper.The wheat centralized seed feeding device was taken as the research object,and the experimental factors were cone angle of type hole,working speed and seed filling gap.The working process of wheat centralized seed feeding device was simulated by discrete element method(DEM).The average seed number of type hole,the variation coefficient of the average seed number of type hole,and the maximum tangential force between seed and seed feeding mechanism were selected as the evaluation indexes.Through the variance analysis of the evaluation indexes by the experimental factors,the optimization objective function was constructed.Using PSO algorithm,the multi-objective optimization was carried out for the wheat centralized seed feeding device.The optimization results show that the best structural combination parameters of the wheat centralized seed feeding device are the hole cone angle of 31.6°and the seed filling gap of 4.6 mm.The validity of the method was verified by simulation and field test.The results show that the PSO algorithm multi-objective optimization method proposed in this paper can provide a reference for the structural improvement and optimal design of the centralized seed feeding device.

Development of a multi-adaptive feeding device for automated plug seedling transplanter

In order to improve the adaptability of the seedling feeding devices to different plug trays for various seedlings,a multi-adaptive plug seedling feeding device for automatic field transplantation was developed.Its efficiency and adaptability have been improved using a seedling delivery device equipped with a row of end-effectors,which were provided with continuous plug seedlings by a compact seedling tray conveyor carrying out a reciprocating action.Each operation for the seedling feeding device could work automatically through a control system.Three categories of plug seedlings,cucumber,pepper and tomato seedlings were tested.The results of the performance test for the prototype demonstrated that the best performance emerged in the cucumber seedlings in 50-cell trays with the highest success rate of 88%at the feeding frequency of 6 groups/min.The lowest success rate was 73.33%for the tomato seedlings in 105-cell trays at the feeding frequency of 12 groups/min.It can be concluded that the automated feeding device developed in this study could be used for various plug seedlings as a result of its strong adaptability.

Hydraulic simulation of the feeding system in the strip casting process

A 1：1 water model of a twin-roll strip caster was set up based on the Froude number（Fr） and Reynolds number （Re） similarity criteria. Fluctuation and the mixing effect in the molten pool of twin-roll strip casting process were analyzed through hydraulic simulation. The height of the fluctuation of the liquid pool surface and the residence time were measured by DJ800 multifunctional monitor under different process conditions. The results show that the casting velocity, the insertion depth and the pool level have a great effect on the fluctuation.

STUDY ON SEED-FEEDING WHEEL WORKING PARAMETERS OF RICE COMPOUND SEEDLINE RAISING MACHINE

The rice compound seedling raising machine is developed according to the request for the rice project seeding plant technology. The principle of the transmission system of the rice compound seedling raising machine and the seed feeding wheel working parameters are introduced. The tests of different structure and working parameters are made in the testing device of the new rice compound seedling raising machine, and the optimizing parameters for designing of seed feeding wheel are obtained.

Optimization design and experiment on feeding and chopping device of silage maize harvester

Horizontal feeding devices and plate hob chopping devices are the key component of silage maize harvester.To solve the problem of feeding blockage,reduce energy consumption,and improve the chopping quality of the chopping device a horizontal different diameter five-rollers device(HDDFD)was designed and the plate hob chopping device was simultaneously optimized and analyzed.Through the dynamic analysis,the feeding conveying speed was determined to be 2.0-4.5 m/s.The distance equation of the actual and theoretical cutting-edge curve and the position of the fixed blade were finally obtained.Single factor and response surface orthogonal tests in the bench site were carried out with feeding speed,rotating speed of chopping cylinder,feeding amount,and feeding direction as influencing factors,standard grass length rate(SGLR),and energy consumption per unit mass(ECPUM)as evaluation indexes.The optimal working parameters for chopping performance could be concluded as a feeding speed of 3.39 m/s,rotating speed of the chopping cylinder of 1016.17 r/min,feeding amount of 8.04 kg/s,and feeding direction of 52.2°.In addition,the SGLR and ECPUM were obtained as 95.35%and 37.63 kJ/kg,respectively.The relative error between the experimental results with round parameter combination and the predicted value was verified to be less than 5%.Field tests verified the reliability of the optimized feeding and chopping device.It can be seen that the HDDFD and optimized plate hob chopping device can meet the requirements of mechanized silage harvesting which obviously improves the working quality and reduce the energy consumption of chopping.