基于EDEM数值模拟的搅拌叶片优化设计

为了解决双卧轴搅拌机的搅拌低效区问题,可旋转搅拌臂与叶片重合,利用搅拌臂来搅拌低效区物料,增强其物料流动性。通过对建立的单搅拌叶片模型进行非线性规划计算,得出其叶片最优参数。为证明该优化结构的准确性,同时建立普通叶片、双排叶片与该优化叶片进行对比,将三种叶片分别装配在同一搅拌筒内导入EDEM模拟搅拌过程。颗粒接触模型采用为Hertz-Mindlin with JKR Cohesion,相关参数通过塌落度数值模拟进行校核。结果发现新型叶片可增大低效区物料速度,改善低效区物料流动性;两轴速度差较小,筒端物料堆积较少从而使物料运转更流畅;可从宏观上增加物料剪切对流运动,微观上增大颗粒动能,使颗粒碰撞更剧烈,物料能够快速达到均匀状态,提高整盘物料搅拌效率。

Optimal Design of Mixing Blade Based on EDEM Numerical Simulation

In order to solve the problem of inefficient zone of twin shaft mixer, themixing arm can be rotated to coincide with the blade to participate in the stirring inefficient material and enhance the material flow. The optimal parameters of the blade were obtained by nonlinear programming of the established single mixed blade model. To prove the accuracy of the optimized structure, the ordinary blade and double row blade were build to compared with the optimized blade.And the three blade were assembled in the same mixing barrel to imported into EDEM to simulate the mixing process.Particle contact model wasadopted as Hertz-Mindlin with JKR Cohesion, and the relevant parameters were checked by slump simulation.The results showed that the new blade can effectively increase the velocity of the material in the inefficient area and improve the material flow in the inefficient zone.The two axisvelocity difference is smaller, and the cylinder end of the material accumulation is less so that the material running smoothly.The new blade can increase the material convection shear movement from the macroscopic view and the particle kinetic energy from the microscopic view to the collision of particles more intense.The material can reach a uniform state quickly so that improve the whole plate material the mixing efficiency.