Design And Experimental Study On Key Components Of Jun-Cao Hammer Mill

Since the introduction of mycorrhiza from Africa to China in 1980 s and the solution of " Fungus forest contradiction " brought by growing pennisetum giganteum,Juncao has been widely promoted and applied.The crushing of Juncao is the biggest part of the initial processing after harvesting,but at this stage,there is relatively little research on the crushing of Juncao,and the development of crushing machinery for Juncao is one of the keys to solve the constraints on the development of mycorrhiza industry.In this paper,the design of crushing equipment for Juncao straw is studied according to the characteristics and crushing requirements of Juncao straw,firstly,the overall design of the crusher is determined,and the preliminary cutting mechanism and hammer blade are optimized;and the key components of the crusher are modeled and simulated according to the design scheme;the collision crushing process of hammer blade and Juncao straw inside the crusher is studied,and the power consumption model of collision crushing is established and the best At the same time,the internal flow field of the shredder was studied to obtain the characteristic law of the flow field;the performance test of the shredder was carried out to compare the shredding performance of the old and new hammer blades and to verify the effectiveness and feasibility of the design scheme.The specific research contents are as follows.(1)Analysis of the characteristics of Juncao straw,according to the characteristics of the crushing method,determine the hammer blade crusher as the overall design scheme,design calculations for each key component of the crusher,and optimize the design of the hammer blade and the primary cutting mechanism,the hammer blade is designed as a new type of hammer blade with a beveled inclination and stepped on both sides,and the primary cutting mechanism is designed using logarithmic solenoid on the moving knife edge line to complete the crusher power and speed Select.(2)According to the design scheme,the key components of the crusher are modeled and simulated.ANSYS was used to analyze the hammer blade and hammer frame plate statically,and the modal analysis of the rotor was simulated to study the first six orders of vibration,and the results showed that the hammer blade,hammer frame plate and rotor all meet the working requirements;ADAMS was used to simulate the dynamic balance of the rotor,and 2200r/min,2500r/min,2800r/min,3100r/min,3400r/min and 3400r/min were studied.The results show that the virtual bearing force at 2800r/min working speed is the smallest.(3)The collision crushing process of hammer blade-mycorrhiza was studied.EDEM was used to simulate the crushing effect of the old and new hammer blades,and the results showed that the number of broken bond bonds of straw particles and the maximum velocity of particles by the new hammer blades were greater than that by the traditional rectangular hammer blades;LS-DYNA was used to simulate the power consumption model of the collision process,and to study the influence law of rotational speed,inclination angle of the ramp and stalk diameter on the average power and collision force,with the minimum average power as the main optimization The minimum average power is the main objective and the maximum collision force is the secondary objective,and the optimization results are obtained according to the regression equation: the rotational speed is 2623.18r/min and the inclination angle of the inclined plane is 7.12° at a Juncao stalk of 22 mm.(4)Numerical simulation of the internal flow field of the shredder using Fluent to obtain the distribution law of the pressure field,velocity field and turbulent kinetic energy field,to obtain the characteristics of the internal flow field of the shredder,the simulation results show that there is a large area of negative pressure around the area below the center of the rotor,while the minimum velocity also appears here,where the velocity change is significant vortex phenomenon,and turbulent kinetic energy is the main cause of the velocity change The turbulent energy is the main reason for the speed change.(5)According to the design plan,the prototype was manufactured and the crushing performance was tested.The test results showed that at2623 r/min,the crusher with the new hammer blade was 13.55% more productive than the crusher with the old hammer blade in terms of k Wh,and the crushing effect was better.