Considering the difference of drag coefficients of particles moving through areas of varying Reynolds numbers, an extra-mass force acting on particles in the active pulsing air field was introduced. Models of the dynamic motion in which the particles both in Stokes and Newtonian fluids, follow as they move in the pulsing air flow were developed. And a computer numerical simulation was carried out that showed the traces of particles with different densities and diameters, but similar aerodynamic characteristics, as they moved through the turbulent flow, to modify and define the parameters of the models. The motion law of tracing spheres was studied in a laboratory active pulsing air classifier with a high-speed video camera and motion particle analyzer. The mechanism of active pulsing air classification was studied. The results show that simulation can predict the observed results with artificial tracing spheres separated by the laboratory equipment. The comparison of the simulation and laboratory experiment results show that the relative errors of velocities are less than 8% for lighter particles and less than 5% for heavier particles.%通过分析不同雷诺数流型下颗粒运动阻力系数的差异,考虑主动脉动气流流场中颗粒运动所受到的附加质量力作用,分别得出斯托克斯和牛顿2种流体的颗粒在主动脉动气流场运动的动力学方程.对直径和密度不同,但空气动力学特性相同的等沉球形颗粒,进行动力学方程的计算机数值模拟,并优化动力学模型参数.在此基础上,应用颗粒高速动态分析系统对示踪颗粒的运动规律进行分析,研究主动脉动气流分选优于传统气流分选的机理.研究结果表明,数值模拟与示踪颗粒的实验室分选试验结果具有很好的一致性,低密度颗粒速度幅值与均值相对误差小于8%,高密度颗粒速度幅值与均值相对误差小于5%.
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