灌水器

Bubbler irrigation is one type of the micro-irrigation. It aims directly at apparatus blockade problem of drip-irrigation system in China.

涌泉灌溉技术是针对滴灌系统使用过程中灌水器容易堵塞，以及农业生产管理水平不高而设计的一种微灌技术。

This paper studies the main geometrical parameter such as angle, height, width, stagger and the upper width in dentation and trapezoid flow path, firstly, uses the single-phase numerical simulation of the computational fluid dynamics technique to analyse the influence of different geometrical parameter on discharge coefficient and flow state exponent of drip emitter. Secondly, uses the two-phases numerical simulation of CFD (1% sand content ) to analyse the influence of the above mentioned geometrical parameter on the contribution regulation of sand and anti-clogging performance. Thirdly, uses the PIV （ particle Tracking Velocimetry ） technique which can see the small-scale flow path to observe and test the trajectories and velocities of solid particles in labyrinth flow path, and analyses the basic factors which can influence the movement characteristic of solid particles and the flow state in flow path.

本文以齿形流道、梯形流道为主要研究对象，以流道转角、流道高，流道宽、偏差量及梯形流道上底宽为主要结构参数，首先应用 CFD 单相流数值模拟技术对不同结构参数灌水器流道水力性能进行模拟，分析了不同结构参数对流态指数和流量系数的影响，其次，应用 CFD 两相流（含沙量为1%）数值模拟技术分析了结构参数对含沙量分布规律和抗堵塞性能的影响，然后，应用 PIV 可视化测试方法测试了固体颗粒在流道内运行轨迹及速度，分析了影响固体颗粒运动特性及流道内流体流态的基本因素，最后，对上述流道结构形式通过模具加工及滴灌带试制，进行了标准化测试（ GB/T 17187-1997 农业灌溉设备滴头技术规范和试验方法与 ISO 标准 ISO /TC23 /SC18 /WG5N4短周期堵塞测试程序），测试结果验证了 CFD 模拟结果，并提出了迷宫结构流道灌水器的抗堵塞设计方法。

Therefore, low-pressure drip irrigation is an important direction of drip irrigation technology in the future.

然而在灌水器工作压力小于5m的低压条件下。

The root-shoot ratio, biomass and proportion of fruit dry weight to biomass were significantly higher with non-pressure subirrigation than that with furrow irrigation.

在番茄成熟期，果实中的干物质分配比例随着灌水器的埋深而增加，而茎和叶中的干物质分配比例呈下降趋势。

Through the comparative analysis that: the arc-tooth flow of hydraulic performance is better than the arc, Adopting optimize the design parameters of the structure, reducing the flow rate of 0 regions, and strengthen vortices regions, improved irrigation arc tooth for hydraulic performance and anticlogging ability, irrigation design recommended by arc-tooth flow structure.

通过对比分析认为：弧齿形流道水力性能优于弧形流道，可以通过结构参数优化设计，减小0流速区域，强化旋涡区，提高弧齿形灌水器的水力性能与扰堵塞能力，灌水器设计中推荐采用弧齿形流道结构形式。

This paper put forward a kind of optimization method based on genetic algorithms for bidirectional flow laterals diameter on sloping field. This method could get the optimal diameter and control criterion of irrigated quality such as average flow and uniformity. Meanwhile, the running control parameter such as the optimum crotched position and intake pressure of laterals could be determined.

提出了一种基于遗传算法的坡地双向毛管管径的优化方法，能获得毛管最优管径和灌水器平均流量、灌水均匀度等灌水质量控制指标，同时能确定毛管最佳分流点位置和毛管进口压力等运行控制参数。

The results obtained from range analysis and variance analysis show that the channel turning angle is the most important factor affecting the flow index, and the flow rate is seriously influenced by the number of channel units, which facilitates settling the problem of increscent flow rate due to the structural optimization.

流量和流态指数的极差和方差分析结果均显示出流道转角对流态指数的影响最显著，而流道单元数对灌水器流量的影响最大，这一结果有助于解决流道经优化后带来的流量增大问题。

At first, the method used the finite element method to design the combination plan of submains and hollow forgings capable of meeting with the requirement of the douches in a micro-irrigation system that the water flux and water-discharging uniformity of the douches be equilibrated, and the pressure heads of the correspondent submain units; next, the parameters of the design and the pressure heads were input into the dynamic programming model and then the optimal combination design of the diameters of various orders of micro-irrigation pipes in the system as well as the pressure heads necessary to operate the system was obtained.

提出了一种基于有限元法和动态规划法的微灌系统管网优化设计方法，该方法先利用有限元法，设计出符合灌水器平均流量和灌水均匀度要求的支管与毛管参数组合方案，及相应的支管单元操作压力水头，然后将这些参数组合与支管单元操作压力水头代入动态规划模型，即可设计出微灌系统各级管道管径的最优组合方案，并确定微灌系统所需的操作压力水头。

The flow characteristics in the flow path of emitters must be understudied roundly in order to design an emitter with high performances.But the labyrinth path was very narrow and complex,and the archetype experiment of the emitters was unreasonable both in the technology and...

通过对迷宫式流道内部流体流动特性的分析，构建了表征迷宫式流道内部流动的数学物理模型；对所选取的目前中国农业灌溉领域最为典型的三种圆柱型灌水器，借助FLUENT6.1 CFD流场软件分析平台实现了流道内部流速分布、涡量分布、紊流强度分布等流动特性的可视化，为新型灌水器流道研制提供一定理论基础。

From analyzing the drip irrigation emitter types and choosing in experiment, the main conclusions are as follows: The best type of subsurface drip irrigation emitter is drip pipe. Under lower water press the stabilization discharge of orifice emitter in soil is three fifth of that in air, which can meet the request of subsurface drip irrigation.

通过对现有滴灌灌水器类型的分析及试验筛选，结果表明，内镶式滴灌管最适宜应用于地下滴灌，在低压运行时，孔口式滴头在土壤中稳定出流量为空气中的 3/ 5 ，基本可以满足地下滴灌的要求；在较高供水压力时，所选取的几种滴头基本上都可以用于地下滴灌。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。