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题名	灌水器抗堵塞及对滴灌系统灌水均匀度的影响
学位类别	硕士
答辩日期	2010
授予单位	中国科学院研究生院
授予地点	陕西
导师	牛文全
关键词	灌溉 抗堵塞试验 灌水均匀度 数值模拟 泥沙
其他题名	Effect of Emitter Clogging on Irrigation Uniformity in Drip Irrigation System
学位专业	水土保持与荒漠化防治
中文摘要	灌水器抗堵塞性能是影响系统成本与灌水均匀度的重要因素之一。它是目前滴灌 系统较难克服的技术难题，也是评价灌水器质量的一个重要指标。本文以齿形迷宫流 道结构灌水器为研究对象，应用计算流体力学(CFD)数值模拟分析软件软件Fluent6.3， 对不同结构参数的齿形迷宫结构灌水器进行了模拟计算，在不同压力下，对不同颗粒 浓度、粒径的浑水抗堵塞情况进行了周期抗堵塞试验分析，并开展了堵塞对田间滴灌 灌水均匀度影响的试验，取得了以下主要结论： （1）固体颗粒在齿尖迎水区随主航道运动，背水区发生旋转；过渡区是颗粒脱 离主航道进入齿尖漩涡区的关键部位，因此，通过调整灌水器结构参数大小，改善过 渡区颗粒的运动可以有效提高灌水器的抗堵性能。 （2）明确了影响灌水器抗堵塞性能的结构参数，齿高是影响灌水器抗堵塞性能 主要的结构参数，其次是齿宽；齿高越大，灌水器的抗堵塞性能越差。采用单相流与 离散相计算相结合的方法分析灌水器的抗堵塞性能，可避免采用欧拉-欧拉两相流占 用计算机内存大，计算不易收敛的缺陷。 （3）浑水中泥沙最大粒径小于0.15mm 时，泥沙含量是影响灌水器抗堵塞性能的 主要因素。当泥沙粒径在一定范围内时，影响灌水器抗堵塞性能的因素依次为：泥沙 含量﹥泥沙粒径级配﹥压力。当压力一定时，影响灌水器抗堵塞性能的因素依次为： 泥沙含量﹥泥沙粒径级配﹥额定流量。 （4）以不同长度段的几个灌水器平均流量代替单个灌水器流量，计算滴灌均匀度 Cu 和均匀度系数Us。综合应用均匀度Cu 和均匀度系数Us 评价灌水质量能有效避免 制造偏差对灌水均匀度的影响。田间灌水均匀度Eu 能更好地反映滴灌系统中灌水器 的堵塞状况；滴灌系统中,应选择流量适当的灌水器,减小滴灌带的铺设长度；根据平 均流量沿滴灌带的变化，当滴头流量为1.38L/h 时，滴灌带长度为80m 以前的平均流 量降低幅度较小，滴头流量为2.0L/h 时，滴灌带70m 以前的平均流量降低幅度较小。
英文摘要	The anti-clogging performance of the emitter is one of the important factor that impact system cost and irrigation uniformity, and an important index to evaluate emitter quality. However, it is also a technical problem in the drip irrigation system which cannot be completely resolved at present. This paper studies dental shape labyrinth path emitter through computational fluid dynamics (CFD) numerical simulation software Fluent6.3, and analyzes the effect of different structural parameters on anti-clogging performance. Besides, the influence of the sediment concentration and size in water on the anti-clogging of emitter and drip irrigation uniformity is studied through periodic anti-clogging and field irrigation experiment. By the above mentioned analysis and studies, this paper gets the main results as follows： （1）Solid particles move along with the main channel in front area of dental tip, but circumvolve in the passed area of dental tip; The transitive area is the key position which the solid particles break away from the main channel to whirl area. So it can advance the anti-clogging performance by improving the solid particles movement state in the transitive area. （2）The height of dental is the prominent factor that affects the anti-clogging performance of emitter, and the following factor is the width of dental; The anti-clogging performance of emitter descend with the height of dental increasing. It can be realized to analyze the anti-clogging performance of emitter through the method combining single-phase flow with discrete- phase, which can avoid the occupying more computer memory and the difficulty of convergence caused by the use of Euler - Euler two-phase flow model. （3）When the sediment diameter in the muddy water is less than 0.15mm, sediment concentration is the main factor affecting the anti-clogging performance. When the sediment diameter within a certain range, the order of the factors which affect the anti-clogging performance is: the concentration of sediment﹥the diameter of sediment﹥work press; When the work press is decided, the order of the factors which affect the anti-clogging performance is: the concentration of sediment﹥the diameter of sediment﹥the rating flow rate of emitter. （4） Cu and Us were calculated through the average flow rate of several emitters in different segments of drip tape instead of single emitter flow rate. It can avoid the influence of manufacture deviation on irrigation quality by comprehensively using Cu and Us computed from the average flow rate. The field irrigation uniformity Eu can reflect the clogging complexion in drip irrigation system better than Cu and Us; In drip irrigation system, choosing suitable flow rate emitter and reducing the length of drip tape are advisable. According to the change of the average flow rate along with drip tape, when the rating flow rate is 1.38L/h, the decreased extension of average flow rate before 80m of the drip tape is less than other parts，and it is before 70m of the drip tape when the rating flow rate is 2.0L/h.
公开日期	2011-09-02
分类号	S275.3
内容类型	学位论文
源URL	[http://ir.iswc.ac.cn/handle/361005/4150]
专题	水土保持研究所_水保所知识产出(1956-2013)
推荐引用方式 GB/T 7714	. 灌水器抗堵塞及对滴灌系统灌水均匀度的影响[D]. 陕西. 中国科学院研究生院. 2010.

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