Design of Pneumatic Conveying Device for Straw Micro-Crusher Based on CFD-DEM Simulation

To solve the problem that the complexity of the internal airflow field of the machine leads to low conveying capacity and affects the crushing and classifying performance of the impact crusher in the process of straw micro-crushing, conveying and classifying, a straw micro-crusher pneumatic conveying device is designed.Based on the force analysis of straw in the conveying channel, this study combines theoretical calculations and numerical simulations to determine the suspension velocity of straw particle, conveying airflow velocity, and volumetric flow rate in pneumatic conveying.Simulation experiments are carried out using the coupled Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) to investigate the airflow distribution patterns and the motion characteristics of straw particles in the process of pneumatic conveying, to clarify the key parameters affecting the conveying efficiency, to determine the optimal values of the key parameters -air inlet width, inlet airflow velocity and flow deflector diameter by the single-factor experiments.A prototype is manufactured, and the relative error in conveying capacity is regarded as an evaluation index to carry out conveying performance tests of pneumatic conveying device.The test results verify the reasonableness of the structural design of the conveying device and the correctness of the theoretical calculations and CFD-DEM coupled simulation results.The findings of this study provide a reference for the design of efficient pneumatic conveying equipment for biomass powder.