粮库气力输送机供料器设计与优化

Design and Optimization of Grain Pneumatic Conveyer Feeder

粮库气力输送系统中,底部供料器是影响整个气力输送性能的主要因素,目前用于输送的供料器结构设计大多数靠经验而来,其结构参数并非最优化,且存在质量流量低,物料速度过小,导致输送距离不够。针对这些问题,通过气力输送机理分析,基于气固两相流理论以及Ansys-Fluent离散模型对出气口与进料口面积比、出气口与进料口中心距、落料口直径等影响底部供料器性能的敏感参数进行了仿真计算。当中心距为140mm,面积比为1:3,落料口直径为120mm,物料输送轨迹较好,出料口颗粒速度可达到62.8m/s,质量流量为21.3kg/s,最高产能可达到40t/h。针对现有市场上通用底部供料器输送速度不高,产能不够等问题,提出了一种可控制落料口物料流量的开闭式供料器。开闭式供料器工作时,混合室和管道内流场稳定,物料颗粒输送轨迹平稳,无回流现象;当落料口全开时,出料口颗粒速度可达到76.3m/s,质量流量为28.2kg/s,最高产能可达到60t/h,大幅度提高了底部供料器供料性能,且能通过开闭式供料器的调节手柄来调节物料质量流量,适应不同产能需求。

Bottom feeder is the key performance of pneumatic conveying equipment for grain storage pneumatic conveying systems. Currently used for conveying feeder structure most relies on the experience and the structural parameters are not the optimal. For the existing equipment,there are many problems to be improved,including that the mass flow rate is too low,the conveying speed of material is small,and the transmission distance is not enough. Aiming at these problems,the sensitivity of performance parameters including the outlet and inlet area ratio U,the outlet and inlet center distance L,blanking the mouth affect base diameter D and so on,were simulated by pneumatic conveying mechanism analysis based on the solid flow theory and Ansys-Fluent discrete model. When center distance L is 140 mm,the area ratio U is 1： 3,blanking opening diameter D of 120 mm,the discharge port can reach the particle velocity of 62. 8m / s,the mass flow rate of 21. 3kg / s,and the maximum production capacity can reach 40 t /h. In the existing markets,the working speed of generic bottom feeder conveyor is not high enough for production capacity and other issues. We also proposed a controllable blanking open mouth closed material flow feeders. When the retractable feeder works,the mixing chamber and the pipeline flow field work stably,and material particles delivery trajectory is smooth without reflow phenomenon. When the blanking mouth opens,the spout particle velocity can reach 76. 3m / s,the mass flow rate is 28. 2kg / s,and the maximum capacity is up to 60 t / h. The capacity requirements of bottom feeders are enhanced significantly,and different feeding performance of the retractable material mass flow feeders can be adjusted by the adjustable handle.