ISWC OpenIR  > 水保所知识产出(1956---)
浑水特性及水温对迷宫流道灌水器抗堵塞性能的影响
刘 璐
Subtype硕士
Thesis Advisor牛文全
2012-05
Degree Grantor中国科学院研究生院
Place of Conferral北京
Keyword灌水器 堵塞 泥沙粒径 含沙量 温度
Abstract

固体颗粒是造成灌水器物理堵塞的直接原因,同时也是最为常见的堵塞形式。在
特定灌水器流道结构下,灌水器抗物理堵塞主要受到固体颗粒特性与水温的影响。本
文以内镶片式斜齿形迷宫流道灌水器作为研究对象,应用类短周期堵塞测验方法,将
小于0.1mm 泥沙颗粒筛分为8 个粒径段,将其分别配制成不同浓度的浑水,分析不
同粒径大小与含沙量组合对灌水器堵塞敏感程度的影响,通过流量降幅和流道内泥沙
淤积情况将8 种粒径段泥沙分为难、易、极易堵塞3 组,进而再针对分组后不同堵塞
敏感程度粒径段的泥沙颗粒以及含沙量设置完全浑水间歇抗堵试验,同时考虑灌水温
度对物理堵塞发生的影响,并运用灌水器平均相对流量qr 和灌水均匀度系数Cu 两项
指标,综合分析评价灌水器整体的堵塞程度,提高含沙水源滴灌技术的应用水平。通
过研究,得出以下主要结论:
1、细小泥沙颗粒对内镶片式斜齿形迷宫灌水器堵塞发生规律与大颗粒泥沙堵塞
情况类似,主要发生在流道进水口与流道拐角处的漩涡区和低速区。灌水器发生堵塞
的位置具有显著的规律性,而发生堵塞的单元却具有随机性。
2、水温对灌水器的物理堵塞影响显著,水温越高,灌水器抗物理堵塞性能越好,
泥沙颗粒在流道内沉积的概率就越低。夏季灌水与冬季灌水相比,灌水器流道内浑水
紊乱程度较高,杂质在流道内存在频繁的粘附、冲刷以及分散的相互作用。颗粒越细,
水温对颗粒在流场内的运动的影响就越大,对于泥沙颗粒粒径小于0.031mm 的粘粒
而言,较高水温对灌水器堵塞程度的影响最为显著,相较而言灌水温度较低的冬季整
体容易造成灌水器堵塞发生。
3、灌水器工作压力对滴头堵塞程度的影响显著,但灌水器堵塞程度并不是随压
力的升高而单调增加的。泥沙粒径和温度也是影响堵塞发生的重要因素,当粒径小于
0.1mm 的浑水进行滴灌,粒径越小越易造成滴头堵塞,且堵塞程度随浑水含沙量的升
高而急剧升高,含沙量、粒径与温度之间还存在一定的耦合作用。当粒径在0.031~0.1mm 之间时,含沙量小于1.25g/L 时,对灌水器抗堵塞性能影响较小,当粒
径小于0.031mm 时,含沙量从1.25g/L~1.5g/L 范围开始,对灌水器堵塞发生的影响
明显提高。
4、单纯采用相对流量难以评估一批灌水器的堵塞程度。本文提出了采用灌水器
平均相对流量和灌水均匀度指标,综合分析灌水器的堵塞状况的方法,并在此基础上
提出了评价堵塞程度的概化模型。但是由于假设误差,公式还存在较大偏差,今后在
堵塞程度评价方面还需进一步的深入研究。
关键词:灌水器,堵塞,泥沙粒径,含沙量,温度

Other Abstract

Physical clogging caused by solid particles are considered as the most common
plugging form of emitter, and also the direct reason that leads to emitter clogging. Under
special emitter channel structure, sediment characteristics and water temperature is a major
factor affecting the anti-clogging performance of emitters. The objective of this study was
to investigate the influence of small sediment particles containing in muddy water on
anti-clogging performance of oblique dental labyrinth channel drip emitters. A total of 8
types of muddy water with different particle size distribution (all less than 0.1 mm) were
tested by short-term clogging tests, and determine the sensitive ranges of particle diameters
and sediment concentrations that cause different clogging levels. According to the relative
discharge of emitters and the deposition sites of sediment particles in the labyrinth channel,
these 8 kinds of particle sizes were classified into 3 clogging levels: difficultly clogged
(DC), easily clogged (EC), and very easily clogged. Afterward, the intermittent drip
irrigation method were adopted to investigate the effects of sediment concentration,
sediment particle size and water temperature on the genesis and processes of labyrinth-path
emitter clogging, and conducted to further prove the results obtained from the short-term
clogging tests Finally. the clogging level of drip irrigation systems was evaluated on the
basis of relative average flow volume (qr) and irrigation uniformity coefficient (Cu) of
emitter flow. The results aim to help in improving drip irrigation methods using water with
high sediment concentration. By the above mentioned analysis and studies, this paper gets
the main results as follows:
First, fine particles caused labyrinth emitter clogging at similar locations as large
particles, which generally occurs at the inlet and corners of the vortex and low velocity of  the flow channel. The sediment particles in labyrinth emitter had random characteristics for
the deposition cell and regularity for the sedimentation position.
Second, the inlet pressure is a main factor affecting the clogging level, and the impact
of the inlet pressure on clogging is neither monotonically increased nor decreased.
Sediment concentration and particle sizes are also primary factors affecting emitter
clogging. When the sediment particle sizes are less than 0.1 mm, the less the sediment
particle size, the easier the emitter will be clogged. In addition, the degree of emitter
clogging rises sharply with the increase of sediment concentrations. There is a coupling
relationship between the sediment characteristics and water temperature of muddy water. If
particle diameters ranges between 0.03 mm and 0.1 mm and the sediment concentration
less than 1.25 g/L do not significantly affect the clogging of emitters. When the sediment
particle sizes less than 0.031 mm, the possibility of clogging rapidly increases at sediment
concentrations of 1.25-1.5 g/L.
Third, The degree of emitter clogging was also impacted by water temperature.
Emitters were less likely clogged by muddy water with higher temperature. The
anti-clogging property of emitters improves with increasing water temperature. The reason
is that the possibility of collision, adhesion, cohesion and separation interaction among the
sediment particles will be higher. The finer the sediment particle sizes, the more prominent
are the influences of the water temperature on anti-clogging performance of emitters. It
was found that in the summer when water temperature was relatively high labyrinth-path
emitters were prone to clogging by sediment with particle sizes less than 0.031 mm.
Four and last, it is very difficult to evaluate the clogging level of the drip irrigation
system by only using the relative emitter discharge. The article proposes a emitters
clogging comprehensive evolution method and generalized model on the basis of relative
average flow volume (qr) and irrigation uniformity coefficient (Cu) of emitter flow.
However, owing to the errors of the parametric hypothesis, the generalized model formula
exist big errors, the comprehensive evolution method of emitters clogging needs further
study.
Key Words:Emitter , Clogging , Sediment particle size , Sediment concentration , Water
temperature

Language中文
Document Type学位论文
Identifierhttp://ir.iswc.ac.cn/handle/361005/8915
Collection水保所知识产出(1956---)
Recommended Citation
GB/T 7714
刘 璐. 浑水特性及水温对迷宫流道灌水器抗堵塞性能的影响[D]. 北京. 中国科学院研究生院,2012.
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