导叶长度对囊体间断面螺旋流流速特性的影响  

Influence of guide vane length on the velocity characteristics of spiral flow in cross-sections between capsules

作　　者：李永业[1] 张奇伟 宋晓腾 鲁一凡 杨小妮[1] 孙西欢[1] 张雪兰[1] 庞雅琦 Li Yongye;Zhang Qiwei;Song Xiaoteng;Lu Yifan;Yang Xiaoni;Sun Xihuan;Zhang Xuelan;Pang Yaqi(College of Water Resource Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学水利科学与工程学院,太原030024

出　　处：《农业工程学报》2021年第19期48-56,F0003,共10页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(51179116)。

摘　　要：为研究囊体表面的导叶长度对囊体管道水力输送特性的影响,该研究以导叶长度为控制变量,通过物理模型试验对囊体间断面的螺旋流流速特性进行了研究。结果表明:不同导叶长度下囊体间各断面的轴向流速分布基本相同,从轴心处沿径向呈现先增大后减小的变化趋势,且随着导叶长度的不断增长,囊体间各断面轴向流速的波动减小,轴向流速分布更加均匀。不同导叶长度下囊体间沿程各断面的周向流速梯度均呈现出先减小后增大的变化趋势,而周向速度最大值和最小值均出现在靠近上游囊体的区域,且周向流速随导叶长度的增加而增大,最大值能达到1.2 m/s。不同导叶长度下,靠近上游囊体区域的径向流速梯度最大,而囊体间中部断面的径向流速梯度较小,且随着导叶长度的增长,同一断面的径向流速分布逐渐趋于均匀。不同导叶长度下,同一测环上的轴向、周向和径向流速均呈现波浪状分布,其分别在–1.2~3.5、–0.6~1.2和–1.6~1.2 m/s之间波动。且受囊体支脚的影响,轴向、周向以及径向流速值在测轴为60°、180°、300°位置处均出现极值。该研究成果可为囊体管道水力输送的优化设计提供理论依据。Hydraulic capsule pipeline refers to the new type of transportation for goods in hollow containers in low carbon and environment-friendly way, particularly for agricultural products. Specifically, the farm products were sealed in airtight containers for point-to-point transportation through fixed pipelines, where the water pressure was taken as the power. Since the guide vanes are added around the capsule body, the water flow will generate circumferential velocity. Therefore, the length of guide vanes inevitably poses a great influence on the distribution and size of circumferential velocity. In this study,experimental and theoretical analysis was used to investigate the velocity characteristics of spiral flow in the cross section of the capsule with the length of the guide vane as the control variable. The results show that the axial velocity distribution of each cross-section was all the same with different lengths of guide vane. Specifically, the fluctuation of axial velocity decreased in each section between capsules, indicating the more uniform distribution of axial velocity, with the increase in the length of the guide vane. There was no major change in the axial velocity, but positive and the same as the water flow direction,with the increase in the length of the guide vane. Furthermore, the circumferential velocity gradient along each section between capsules first decreased, and then increased with different guide vane lengths, while the maximum and minimum circumferential velocity appeared near the upstream capsule. More importantly, the length of the guide vane presented the greatest influence on the circumferential flow velocity. The circumferential flow velocity increased with the increase of guide vane length, with a maximum of up to 1.2 m/s. The value of circumferential velocity was positive or negative, indicating that the circumferential velocity was divided into two directions, clockwise and counterclockwise along the circumference. The radial velocity gradient was the largest in the area near t

关 键 词：流场 试验 管道 水力输送 囊体 导叶长度 螺旋流 流速特性 

分 类 号：S377[农业科学—农产品加工]