管径比对脉冲气流干燥器干燥过程的影响

Influence of Diameter Ratio on Drying Process in Pulsed Pneumatic Dryer

为了考察脉冲气流干燥器的管径比对干燥器干燥性能的影响,设计5种不同管径比的脉冲气流干燥器进行对比研究,利用计算流体动力学对干燥器的干燥过程进行数值模拟。结果表明:管径比越大,被干燥颗粒在干燥器中的运动越紊乱,颗粒停留时间越长,颗粒的湿含量越小;干燥器中的压力损失随着管径比的增大而增大,导致能耗增加;存在一个综合效果较优的管径比,该值应在综合干燥效果和压力损失的情况下进行选取。

To investigate the effect of diameter ratio in a pulsed pneumatic dryer on drying performance, a comparative study was conducted between five kinds of pulsed pneumatic dryers with different diameter ratios. By the computational fluid dynamics technology, the drying process of the dryers was numerically simulated. The result shows that with the increase of the diameter ratio, the movement of particles in the dryers becomes more and more disordered, which prolongs residence time of the particles and results in a better drying effect. The pressure loss increases with the increase of diameter ratio, which leads to improvement of energy efficiency. There is a best diameter ratio in the pulsed pneumatic dryer. The value should be chosen based on the comprehensive influence of the pressure and drying effect.