Design And Experiment Of Pneumatic Bait Casting Machine Based On EDEM-Fluent Coupling Simulation

Feeding operation is an important link in aquaculture process and a key step to realize the increase of aquaculture production,but unreasonable feeding will lead to the reduction of aquaculture objects and water pollution.Aimed at the present situation of domestic fresh water breeding process of cast low feeding efficiency,bait scatters unevenly,the problem of large labor intensity,this topic has designed a kind of based on pneumatic conveying feeding device,using theoretical analysis,solid and gas coupling simulation,experimental test,the method of combining quantitative feeding,realized the bait uniform scatters the goal.Compared with the traditional pneumatic feeding device,this device integrates feeding,feeding and throwing into one,shorts feeding time and effectively solves the problem of uneven feeding in small water area.The main conclusions are as follows:(1)The overall structure of pneumatic bait casting machine is determined.The overall structure includes bait feeding device and pneumatic conveying device: bait feeding device includes feeding parts and feeding parts;The pneumatic conveying device includes mixing parts and scattering parts.Feeding parts for the material box,the volume of 45 L,20kg filler;The feeding part is a volume roller,with 4 cavities designed.The volume of the cavities is 0.2L,which can be filled with 130 g bait.The mixed part is venturi pipe,whose pipe diameter is 50 mm,small diameter is 30 mm,contraction angle is 28°,expansion angle is 11.4°;The casting part is a nozzle with a cone angle of 80°,an expansion angle of 60° and a drawing angle of 10°.(2)The simulation analysis of bait supply device and pneumatic conveying device was carried out.In order to explore the shunt performance of shunt components under different connection modes,EDEM was used to simulate different connection modes of shunt components.The results showed that the feed could be evenly distributed to both sides of the pipes by connecting the diverging parts.In order to explore the factors affecting the movement trajectory of bait,EDEM-Fluent was used for simulation analysis.The simulation results show that the inlet velocity,cone angle and extension angle affect the trajectory of feed flow,and the better trajectory of feed flow is between25m/s to 35m/s,cone angle number 75° to 85°,and extension angle number 50° to 70°.(3)The simulation and prototype test of pneumatic bait casting machine were carried out.Taking inlet velocity,cone angle and spread angle as experimental factors,and variation coefficient of feed distribution as evaluation index,the effects of each influencing factor on the index were analyzed by single factor simulation experiment.The optimum parameter combination of pneumatic bait casting machine was obtained by orthogonal test and verified by prototype test.The experimental results show that the optimal parameters of pneumatic bait casting machine are as follows:airflow inlet velocity is 29m/s,cone angle is 79°,extension angle is 56°,and the variation coefficient of feed distribution is 0.216.The variation coefficient of bait distribution is 0.228,which is very close to the simulation data.The bait crushing rate and utilization rate of the test prototype were 0.377% and 96.7% respectively.The casting performance of the prototype is better.