米粉挤丝机挤出流场与温度场模拟仿真分析
Simulation analysis of extrusion flow field and temperature field of rice noodles extruder
张梦瑶 1张克 2杨云任 1何亚凯 2王文杰 1李振龙 1赵丹 2吕黄珍2
作者信息
- 1. 中国农业机械化科学研究院集团有限公司,北京 100083;农业农村部农产品加工装备重点实验室,北京 100083
- 2. 中国包装和食品机械有限公司,北京 100083
- 折叠
摘要
针对单螺杆挤丝机挤出米粉过程中,流场与温度场变化复杂、检测困难的问题,结合单螺杆挤丝机和米粉特性,通过Fluent软件进行数值模拟仿真研究.构建变螺距螺杆及套筒的三维模型,结合实际加工中的螺杆转速、进料量及机筒接触面温度等关键工艺参数,采用滑移网格模型进行非定常流动模拟,并对仿真结果进行试验验证.仿真结果表明,流场进出口压差最高可达 5.58 MPa,沿z轴的运输速度区间为 0.374～0.782 m/s,且缓慢下降;螺杆转速由 50 rad/s上升至70 rad/s,黏性耗散功率由 16 217.00 W上升至 30 974.96 W,截面温度离散系数由 3.48%上升至 4.29%;喂料电机频率由10 Hz上升至 25 Hz,黏性耗散功率由 20 511.41 W上升至 23 066.87 W,截面温度离散系数由 7.80%下降至 3.65%;壁面温度由 353.15 K上升至 373.15 K,黏性耗散功率由 23 100.72 W下降至 23 032.85 W,截面温度离散系数由 3.27%上升至4.19%.验证试验表明,螺杆转速、进料量及壁面温度对温度上升速度的影响与仿真结果相符.研究为米粉熟化过程温度的精准控制与工艺参数的优化提供理论依据.
Abstract
Aiming at the problem that the flow field and temperature field of rice flour extrusion in the process of rice flour extrusion of single screw extruder are complex and difficult to detect,combined with the characteristics of single screw extruder and rice flour,the numerical simulation was carried out by Fluent software.A three-dimensional model including variable pitch screw and sleeve was constructed.Combined with the key process parameters such as screw speed,feed rate and barrel contact surface temperature in actual processing,the unsteady flow simulation was carried out by sliding mesh model,and the simulation results were verified by experiments.The simulation results show that the maximum pressure difference between the inlet and outlet of the flow field can reach 5.58 MPa,and the transport speed along the z-axis ranges from 0.374 m/s to 0.782 m/s,and decreases slowly.When the screw speed increases from 50 rad/s to 70 rad/s,the viscous dissipation power increases from 16 217.00 W to 30 974.96 W,and the cross-section temperature dispersion coefficient increases from 3.48%to 4.29%.When the frequency of the feeding motor increases from 10 Hz to 25 Hz,the viscous dissipation power increases from 20 511.41 W to 23 066.87 W,and the cross-section temperature dispersion coefficient decreases from 7.80%to 3.65%.The wall temperature increases from 353.15 K to 373.15 K,the viscous dissipation power decreases from 23 100.72 W to 23 032.85 W,and the cross-section temperature dispersion coefficient increases from 3.27%to 4.19%.The verification test shows that the influence of screw speed,feed rate and wall temperature on the temperature rise speed is consistent with the simulation results.This study provides a theoretical basis for the development of rice flour extrusion machine control system and the precise control of rice flour ripening process temperature and the optimization of process parameters.
关键词
米粉挤出/流场模拟/温度场分布/滑移网格模型Key words
extrusion of rice noodles/flow field simulation/temperature distribution/sliding mesh model引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据