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Fluids Mechanics in Lifting Devices

 * * The use of fluid power has developed along with civilization. The natural movements of air and water were probably the original sources of power used by early humans.


 * It is speculated that the use of crude sails to reduce the effort to move boats was the initial attempt to harness the natural power. These early applications were followed by the development of more sophisticated systems, which eventually lead to the development of the windmill.


 *  Flowing water in rivers and streams was also used to assist in transporting boats and materials. The Egyptians, Persians, and Chinese built dams, ditches, and gates to form elaborate water-controlled and irrigation systems || [[image:SailPowerBoat.png width="298" height="278" caption="Fig 8 An early example of fluid power (wind)"]] ||
 * media type="youtube" key="wozXqEMXqsE" height="315" width="420" || media type="youtube" key="g6aErhwFXsg" height="315" width="420" ||
 * [[image:WaterScrew.png width="359" height="230" align="center" caption="Fig 9 Archimedes design of the water screw."]] || * These various applications eventually led to the development of variations of the waterwheel to lift water for irrigation purposes and turn simple machines.


 * These early uses of fluid power were dependent on vast quantities of low pressure air and water supplied by nature. It is doubtful whether the physical principles associated with modern hydraulics, and pneumatics was fully understood in early history or even at the beginning of the industrial revolution.


 * Archimedes is credited for the discovery of the principle of buoyancy in the third century BC.


 *  Archimedes’ principle state that a body immersed in a fluid is buoyed up by a force equal to the weight of the displaced fluids. The principle applies to both floating and submerged bodies and to all fluids, i.e., liquids and gases. He is also credited with the invention of the water screw.


 * This device has been used to lift water and move water for centuries, and this invention has moreover, influenced in the development of pumping devices in the fluid power field. ||
 * * Today’s car industry can be used as a typical example for the use of fluid power.


 * The body of the vehicle is formed by huge hydraulic-powered presses.


 * Hydraulically-controlled resistance welding equipment assembles those parts, while untold numbers of the hydraulic and pneumatic tools are used for the production of additional parts during the final assembly process.


 *  Intricate fluid power systems are also used for the steering, braking, and ride control systems of the vehicle, which promotes safety and comfort of the driver and passengers. || [[image:CarIndustry.png width="238" height="256" align="center" caption="Fig 11 Automobile assembly line."]] ||
 * [[image:WindMills.png width="198" height="206" align="center" caption="Fig 10 Windmills farm"]] || * Windmills have experienced a significant resurgence as prime movers in the windmill farms currently used for electrical generation.


 * As energy costs rise, so does interest in harvesting this free energy. To say the least, fluid power has grown tremendously during the 1900s and into the 2000s.


 *  Current space technologies, manufacturing industry demand, and consumer interest indicate that this growth will continue into the 21st century. ||

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