【摘要】 为提高红外滚筒干燥机内谷物的干燥效率和干燥品质,本文采用离散单元法研究滚筒内颗粒混合过程。本文在滚筒内设置不同数量和高度的抄板,颗粒粒径采用均一粒径,对内外初始分布方式下的混合过程进行模拟。通过Lacey指数对混合均匀性进行定量分析,同时提出"暴露时间"的指标来分析颗粒的受热均匀性。结果表明,滚筒内颗粒的初始分布影响着表观混合效果;抄板的加入使得颗粒混合过程明显加速,当抄板高度L=0.5R(R为滚筒半径)时混合速率和混合程度达到最佳值;当抄板高度L=0.5R,抄板数n=3时滚筒内颗粒的受热均匀性最佳,而抄板数量对混合过程的影响则不大。更多还原

【Abstract】 To improve the dry efficiency and quality of grain in infrared drum dryer,the particle mixing process in infrared drum dryer is studied in this paper based on the discrete element method. The mixing process is simulated with the inner-outer initial grain distribution,uniform grain size,and different type of baffles in the infrared drum dryer. Lacey index and Exposure Time is put forward to quantitatively analyze the mixing and heating uniformity of particles respectively. The result shows that the initial distribution affects the apparent mixing result. Grain mixing process is accelerated obviously when baffle is added. The mixing rate and mixing degree has the optimum values when baffles height L = 0. 5 R( R is the radius of drum). The heating uniformity of grain reach the best value when L = 0. 5 R,and the baffle number n = 3. However,the number of baffles have little effect on mixing process.更多还原