Fluid simulation analysis and elbow structure optimization of sweet potato seedling recovery machine

doi:10.13733/j.jcam.issn.20955553.2022.02.002

Abstract

Abstract: The structure and shape of the conveyor tube have a significant influence on the performance of the sweet potato seedling recovery machine. In order to reduce the power consumption of the sweet potato seedling recovery machine and increase the recovery rate of the sweet potato seedlings, the CFX software was used to calculate the gassolid twophase flow in the throwing device and analyze the twophase flow distribution law in the throwing device. The simulation results show that the threestage radian combination scheme of the upper wall of the conveying elbow, the contraction transition of a single radius of curvature, and the appropriate opening of the fan inlet are helpful to improve the performance of the throwing device. Taking the arc of the elbow, the radius of curvature of the shrinkage curve, and the entrance opening as the test factors, the specific power consumption of the throwing device of the recovery machine and the recovery rate of the sweet potato seedlings were used to conduct a threefactor threelevel central combination test and test verification. The optimized test results show that the arc of the upper wall of the conveying elbow adopts the threesegment arc are R1 026+R513+R256 mm, the radius of curvature of the shrinkage curve is 850 mm, the fan inlet opening is 216 mm, and the specific power consumption of the throwing device and the recovery rate of sweet potato seedlings are 660 m2/s2 and 93.23%, respectively. The experiment shows that the specific power consumption is reduced by 9.71% after the optimization and improvement of the throwing device, and the recovery rate of sweet potato seedlings is increased by 1.04%, which proves the effectiveness of the simulation optimization of the conveyor elbow of the potato seedling recovery machine.

Key words: sweet potato seedlings, recovery machine, conveying elbow, central combination test, specific power consumption, recovery rate

摘要： 为降低甘薯秧回收机功耗，提高甘薯秧回收率，利用CFX软件求解计算抛送装置内气固两相流，仿真对比分析不同输送弯管结构时抛送装置内两相流分布规律，以确定输送管合理结构参数。仿真结果表明：输送弯管的上壁面三段弧度结合方案、单一曲率半径收缩过渡、适当的风机入口开度有助于提高抛送装置性能。以弯管弧度、收缩曲线曲率半径、入口开度为试验因素，以回收机抛送装置比功耗、甘薯秧回收率为响应值进行三因素三水平中心组合仿真优化试验并进行试验验证。结果表明：输送弯管上壁面弧度采用三段弧组合R1 026 mm+R513 mm+R256 mm，收缩曲线曲率半径为850 mm，风机入口开度为216 mm时，抛送装置比功耗、甘薯秧回收率分别为660 m2/s2、93.23%。对比试验表明抛送装置优化改进后比功耗降低9.71%，甘薯秧回收率提高1.04%，证明薯秧回收机输送弯管仿真优化的有效性。

关键词: 甘薯秧, 回收机, 输送弯管, 中心组合试验, 比功耗, 回收率

CLC Number:

S225

Mu Guizhi, Qi Xieteng, Zhang Chen, Wang Xu, Lü Zhaoqin, Zheng Wenxiu. . Fluid simulation analysis and elbow structure optimization of sweet potato seedling recovery machine[J]. Journal of Chinese Agricultural Mechanization, 2022, 43(2): 8-14.

穆桂脂, 亓协腾, 张琛, 王旭, 吕钊钦, 郑文秀, . 甘薯秧回收机输送管流体仿真分析与弯管结构优化[J]. 中国农机化学报, 2022, 43(2): 8-14.

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