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搜索结果: 1-15 共查到Sprinkler相关记录15条 . 查询时间(0.14 秒)
A two-year experiment was conducted in the desert west of the Nile Delta to study the effect of applying fertilizers and other agronomic chemicals through sprinkler irrigation water (a technique refer...
In the past few decades, several coefficients of uniformity were developed to express the uniformity of water distribution for different sprinkler irrigation systems. Christiansen's uniformity coeffic...
Ballistic simulation of the spray sprinkler for self-propelled irrigation machines requires the incorporation of the effect of the jet impact with the deflecting plate. The kinetic energy losses produ...
This study examined changes in some soil hydrophysical, chemical properties and wheat yield (grain; straw yield, N, P, K, Protein and carbohydrates contents) as trends under two cultivated period 10 a...
合理配置与优化设计喷灌机组有助于实现机组装置效率最大化,有效降低能量消耗。以能耗最小为目标,以水泵-管路运行工况、喷头最小工作压力和喷头压力极差率为约束条件,以喷头配置数量、管道直径和末端喷头压力为决策变量,建立轻小型移动喷灌机组优化数学模型,提出基于遗传算法的优化设计方法。在满足喷灌设计参数条件下,模型与算法能够优化喷头数量、管道直径,还能够对系统流量、压力、效率、单位能耗等工作参数进行计算与设...
基于显式动力分析软件ANSYS/LS-DYNA,建立了摇臂式喷头摇臂绕轴旋转、碰撞喷体的有限元分析模型,在3种摇臂转动角速度和喷体安装弹性橡胶垫与否的组合工况下,对摇臂与喷体的碰撞过程及动应力分布进行了计算模拟。结果表明,PY140型摇臂式喷头在转动角速度400(°)/s时,计算的碰撞动应力峰值为42.3MPa,与试验值的误差小于0.5%,预测的发生位置距离摇臂转轴中心15cm,与试验结果相同。摇...
Efficient crop coefficient (Kc) estimation is very important to adequately determine water use of a selected crop. In this study, crop coefficient was determined for upland rice (NERICA) under a sprin...
There are many possible layouts for transporting water from its source to hydrants. That is why the most economical solution must be found. In practice, trial and error procedures are usually applied ...
为了扩大全射流喷头压力适用范围,提出在喷管处加转折角增加喷头固有驱动力矩。转折角喷管的重要结构因素包括转折角角度和转折角力臂长度,理论分析推导出全射流喷头步进旋转时所受总驱动力矩和旋转角方程。对不同转折角角度或转折角力臂组成的7种不同喷管进行了试验,测量性能指标包括步进角度、步进频率、射程和均匀系数。结果表明:试验值与理论分析具有较好的一致性;工作压力影响射程、均匀系数和步进频率,对步进角度影响不...
Performance assessment (PA) of irrigation and drainage systems has been an important area of research and debate in recent years. The present study was carried out to determine some performance parame...
Deep tillage at a 45° angle has been a recommended practice since the mid-1970s on most Mississippi Delta cotton soils. This practice disrupts hard pans and allows deeper wetting of the soil profile w...
A new irrigation scheduling tool called the UGA EASY Pan (Evaporation-based Accumulator for Sprinkler-enhanced Yield) allows remote observation of evaporation that can be correlated with crop water us...
Rice is currently produced on approximately 400,000 acres in the Texas Coastal Prairie. This rice consumes 1.8 million acre-feet of water a year or 13 percent of Texas' renewable water resources. The ...
A study was conducted to develop automated pivot sprinkler irrigation systems and determine if such systems use less water and energy than manually operated systems. The study was conducted near Earth...
In 1968 and 1969, moisture level treatments were applied to tomatoes and citrus. Light sprinkler applications and white acrylic paint were applied to leaf canopies of tomatoes and citrus. Moisture use...

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