灌溉泵在极端干旱条件下BETVICTOR体育官网失效

灌溉和泵系统开始

人类生存的能力始终与文明可靠地获得普遍基本必需品，特别是食物和水的能力有关。不幸的是，水并不总是以正确的方式流动，地形也并不总是适合我们。没有水，再肥沃的土壤也毫无用处。最终，浇水太少或根本不浇水的作物会死亡，那片土地上的人们很快也会遭受同样的命运。然而，随着时间的推移，人类已经能够分析和理解他们面临的问题，然后发明创造性的进步。为了利用手头的资源，尽管不容易获得，灌溉的概念就产生了。工程灌溉的第一个例子来自古埃及及其邻国美索不达米亚。通过利用地形和河流的自然洪水，古埃及人将附近的尼罗河变成了他们农业需要的恒定的肥沃资源。美索不达米亚人对他们的河流底格里斯河和幼发拉底河也做了同样的事情。由于与河岸的工作涉及洪水周期，早期的灌溉大多建立在被动建设的概念上。 Flood cycles were well recorded when communities, during the late summer through the end of the year, would divert the flooded rivers into the fields for 40 to 60 days. The water was then drained back into the river at the right time during the cycle so the silt for harvest could be used by the farmers. The first water displacement device was implemented in 1700 B.C. in ancient Egypt—the shadoof or shaduf. It was a hand operated device that consisted of a pole with a bucket. A counterweight was placed on the opposite end so users were able to easily lower and raise the bucket. The device allowed anyone to easily lift more than 2,500 liters of water a day from the Nile. In addition to the shadoof, Hellenistic engineers also had the water wheel, which they used for irrigation and power. Later came the qanat, a device that used groundwater as the primary source of crop irrigation. By digging a vertical well through a slope and then digging one or more horizontal tunnels to the lower end of the slope, the qanat allowed the water source and outside flowing water to follow the same path down via gravity and into the exit slope. Though originally implemented in Mesopotamia as early as 550 B.C., the qanat was a historical technique that allowed for a constant source of water for any area. Around 20,000 are still in use today. The Archimedes Screw would come almost two centuries later. By placing a screw inside a hollow tube with one end placed in water, water was slowly scooped up and through the column each time the screw turned. The development of the technique meant that waterways could be opened and closed, giving humanity the ability to send water as far as 100 miles from the source. Most importantly, it allowed the civilization around 250 B.C. to use an extremely reliable irrigation technique. With irrigation and the positive livelihood of agriculture, it is no surprise that the number of acres of irrigated land within the U.S. reached almost 20 million by the 1800s. Over the next 200 years, the number would explode to an astounding estimated 600 million acres. Without modern irrigation, cities and towns such as Los Angeles, Phoenix and San Jose would not obtain nearly enough water to support the growing population. Luckily, the world went through an industrial revolution that sparked the era of machines, one of which affected the process of irrigation forever: pumps. Denis Papin first built a centrifugal pump in the late 17th century, paving the way with the use of straight vanes. British inventor John Appold then introduced the curved vane in 1851. Most modern pumps contain impellers, which convert kinetic energy by spinning radially and creating pressure and then displacing it throughout the pump. Specific vertical pumps, especially in the irrigation industry, are referred to as “axial flow” pumps. Axial pumps generally have propellers and are designed to push an immense amount of water forward. These pumps are very low pressure and are mostly used to move a large water mass. While civilization was reaching a high point when it comes to irrigation, continual maintenance of irrigation systems is still needed.