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滴头水力性能与抗堵塞性能试验研究

论文标题:滴头水力性能与抗堵塞性能试验研究
Study on the Hydraulic and Anti-clogging Performance of Emitters
论文作者 王建东
论文导师 李光永,论文学位 硕士,论文专业 农业水土工程
论文单位 中国农业大学,点击次数 16,论文页数 62页File Size3052k
2004-06-01论文网 滴头;水力性能;抗堵塞;流道结构
emitter,hydraulic performance,anti-clogging,the structure of flow passage
滴头是滴灌系统最为关键的部件之一，因此，对滴头水力性能和抗堵塞性能的研究有着极为重要的意义。本文的研究内容和实验结果分析主要包括5个部分：(1)研制开发了一种灌水器水力性能和抗堵塞性能实验测试装置。该装置既能测定灌水器的水力性能(包括流量压力关系、水温对流量的影响、灌水器制造偏差等)，又能测定灌水器的抗堵塞性能(包括物理堵塞和化学堵塞)。(2)对7种典型流道结构形式的滴头分别在不同流道长度下的水力性能进行了研究。比较了不同结构形式滴头的流态指数和相同工作压力和流量下的流道长度与流道截面积，分析了其抗堵塞性能，得出了较佳的几种流道结构，并建立了描述滴头流量与工作压力及流道长度之间关系的函数模型。(3)以齿形流道结构中齿角度、齿间距、齿高、流道深度为实验因素，每个因素选用4个水平，进行正交实验，研究了齿形流道结构参数对滴头水力性能的影响。根据实验结果分析了各因素之间的最优组合，分析了各因素对滴头流态指数、滴头流量的影响显著性，并在流道长度一定的情况下，建立了10m工作水头下滴头流量与流道结构参数之间的模型。(4)在参考ISO抗堵塞实验国际标准草案的基础上，制定了抗堵塞实验方案，研究了齿形流道结构参数对滴头抗堵塞性能的影响。根据抗堵塞实验结果，分析了各参数之间的最优组合和各因素对滴头抗堵塞性能影响的显著性。此外，还分析了流道宽度、滴头流量与齿形滴头抗堵塞性能之间的内在关系。(5)根据水工模型定律，放大滴头原型，探索了其与滴头原型的水力相似性。
Emitters are one of the key parts of drip irrigation system. Thus, the study on the hydraulic performance and anti-clogging ability of emitters has important significance. The content and results analysis in this paper conclude the following four parts: (I) An equipment for testing the hydraulic performance and anti-clogging performance of emitters has been developed. This equipment can test the emitters" hydraulic performance, which includes the relationship between pressure and flow rate, the impact on flow rate by water temperature, manufacturer"s coefficient of variation of emitters. It also can test the emitters" anti-clogging ability, which comprises physical clogging and chemical clogging. (2) Hydraulic performance of seven typical emitters forms were studied under different flow passage length respectively through experiments. The exponent of flow state of these emitters was compared. Under the same working pressure and flow rate, the flow passage length and cross-section area of the seven different emitters were compared. According to those results, the anti-clogging ability of emitters was analyzed and several good structural form of flow passage were obtained. In addition, regression model describing the relationship among flow rate, the length of flow passage and work pressure was set up. (3) Quadrature experiment consisted of four experimental factors including dental angle, space between dental structure, dental height and the depth of flow passage of dentate, any one of which has four different values. How these dental structural parameters affected hydraulic performance of dentate emitters was studied. The optimal combination among structural factors was obtained through experimental results. In addition, which experimental factor has significant influence on the exponent of flow state and flow rate of these emitters was analyzed. Finally, several regression models describing the relationship between flow rate and structural parameters of flow passage were set up under the condition of certain flow passage length and 10m working pressure. (4) Anti-clogging experimental scheme was established on the basis of referring to ISO Anti -clogging experimental scheme which is still under discussion. How these structural parameters affected anti -clogging ability of dentate emitters was studied. According to the test results, the optimal combination among structural factors was obtained and which structural factor has significant influence on the anti -clogging ability of these emitters was analyzed. Furthermore, the relationship among flow passage width, flow rate of emitters and anti -clogging ability of dentate emitters was analyzed. (5) Finally, an enlarged emitter model was designed according to hydraulic engineering model principle, which was used for exploring hydraulic similarity between the original model and the enlarged model

论文标题:新型抗堵塞滴头的研制
Research on the Resisting Clogging Emitter
论文作者 杜敏
论文导师 吴普特,论文学位 硕士,论文专业 农业水土工程
论文单位 西北农林科技大学,点击次数 13,论文页数 54页File Size2297k
2004-06-15论文网 堵塞; 滴头 ; 迷宫流道 ; 快速成型
Clogging; Emitter Labyrinth ;Channel Rapid ;Prototyping
滴头堵塞是滴灌系统中存在的主要问题，轻则使滴灌系统的滴头流量降低，影响滴水的均匀度；重则导致滴头报废，大量的滴头堵塞会使滴灌系统无法正常工作，严重影响滴灌技术的推广和应用。因此本论文旨在研究开发一种新型抗堵塞滴头,提高滴头抗堵塞能力、延长滴头使用寿命、降低过滤要求、减少系统投资。主要研究结果如下：1、本研究在分析了国内外抗堵塞滴头设计理论和结构特征的基础上，提出一种“可变流道”结构的新型抗堵塞滴头。该滴头流道由两部分结构密合而成，当滴头在正常工作时，流道处于密合状态,构成水流通道,且具有很好的消能效果；当滴头开、关瞬间，由于压力的变化使得构成流道的两部分结构分离，过流断面增大，从而将堵塞流道的杂质冲刷掉。通过室内水力性能测试及室外抗堵塞性能试验测得该滴头流态指数为0.501、流量系数为0.484、滴头流量压力关系公式为q=0.484H0.501，抗堵塞性能良好。2、由于迷宫流道的复杂性，目前对其内部水力性能的研究还没有成熟的理论依据。基于这种情况，我们在现有水力学理论公式的指导下，采用参数化、模块化的迷宫流道设计思想。设计出以“几”字型单元为最小流道设计单位，通过改变构成流道的最小单元个数来构成不同的迷宫流道。接着由参数化、特征建模软件Pro/E进行滴头的三维CAD实体模型设计，便于结构参数的修改。3、本研究采用了先进的激光快速成型技术进行抗堵塞滴头样品制作，其样品可直接用于性能测试，大大缩短了滴头的开发周期和成本，为试验的顺利完成铺垫了道路。
The Clogging of emitter is common in the dripping irrigation system, which can reduce flow, even makes the drip irrigation system halt work. Therefore this subject aims at developing a new emitter , cutting down filter, lengthening the life span and reducing the system investment.Based on the analysis of the design theory of emitter, the author puts forward “ variable channel” emitter. Namely two parts compose the channel. When working, two parts is close to make channel to flow, otherwise, two parts is part and the channel dooms to flush. By way of indoor tests and field tests, some data can be obtained. The form index is 0.501，the flow coefficient is 0.484, the formula: qk = kdHx.Because the complexity of labyrinth channel, at present there is not exclusive theory. Based on this kind of circumstances, we are under macroscopic guidance of theory of hydraulics, and use the thought of parameterization and modularization to design.At the same time, the Rapid Prototyping is used in the subject, which shortens the period of development and reduces the cost.