【作者】 陈雪；

【导师】 吴普特； 范兴科；

【作者基本信息】 西北农林科技大学 ， 农业水土工程， 2008， 硕士

【摘要】 滴灌灌水器是滴灌系统的核心部件,它的性能和质量直接决定着灌溉系统的工作性能。而灌水器的堵塞问题又是一直以来难以解决的瓶颈问题,因此研究灌水器内部结构参数与其水力性能及抗堵塞性能的关系具有重要的意义。针对目前国内常见的几种迷宫流道滴灌灌水器,本研究主要以最基本的三角形迷宫流道结构为研究对象,以齿尖角及参差量为主要控制因素,设计了十六种不同结构形式的三角形迷宫流道形式滴头,采用CFD数值模拟、样品制作及室内和室外试验测试相结合的方法,研究了灌水器的流道结构特征、端面尺寸等因素对灌水器水力性能和堵塞性能的影响,得出以下主要结论:(1) CFD数值模拟结果与试验测试结果的流量偏差在20%以内,分布趋势有良好的相关性,总体差异并不显著,结果与实测结果基本吻合。因此利用CFD模拟灌水器流道内部流场是可行的,可以为滴头的流量与水力及抗堵塞性能预测提供依据。(2)在考虑灌水器的消能效果及对流量的要求的前提下,齿间参差量越小、齿间角越大其流道的抗堵塞性能越好。建议齿尖角宜选择在60°左右,齿尖参差量宜选择在-0.25与+0.25之间。(3)齿尖参差量的大小对滴头的抗堵塞性能起了主要的作用,齿尖角度次之。因此从抗堵塞性能和生产成本及加工工艺来分析,较大的流道截面积和适中的齿尖角度有助于提高抗堵塞性能和减少生产成本。(4)从试验研究过程可以说本文尝试的:流道参数化设计-流道流场模拟-灌水器原型制作与成型-灌水器水力与抗堵塞性能试验是有效的灌水器流道结构设计方法。更多还原

【Abstract】 Drip emitter is the key component of drip irrigation system. Its performace and quality will directly determine the working performance of the whole drip irrigation system. However, the clogging of drip emitter is a serious problem which has not been solved yet. Because of this, it is very significant to study on the relationship between the structure parameters of emitter channel and the hydraulic and anti-clogging performance. Therefore, this research chooses triangular labyrinth channel as study object, angle of dentations and stagger dentations as controlling factors of structure, then designs sixteen different kinds of structures of triangular labyrinth channel, according to several kinds of labyrinth channels in China. In the end, it studies on how the factors of structure characteristics and section size of labyrinth channel influence the anti-clogging performance of emitter using the method of CFD numerical simulation, Sample Manufacturing and indoor and outdoor experiment. The main results show that:(1) The errors of discharge between CFD numerical simulation and experimental testing are all smaller than 20%. The distribution tendency of the two results has a good relativity without significant differences and the two results basically tallies. It means that it is feasible to use CFD simulates internal flow field of emitter and the final results will provide theoretical basis for predicting emitter discharge and hydraulic and anti-clogging performance.(2)On the consideration of the requirement of discharge and energy dissipation effect, the smaller stagger dentations are and the larger angle of dentations are, the better the anti-clogging performance of emitter is. Therefore, it suggests that angle of dentations should be controlled at about 60°, and the stagger dentations should be chosen between -0.25 and +0.25.(3)It reveals that the size of stagger dentations plays an key role in the performance of anti-clogging, then is the angle. So a larger section area and a mezzo angle is helpful to improve the anti-clogging performance and decrease the production cost.(4)It can be concluded from the whole procedure of design and experiment that parameterized design of the emitter channel-simulatio of the flow field-prototype making and forming-hydraulic and anti-clogging performance testing is a effective method of emitter designing.更多还原