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Introduction:Wind energy is one of the most reliable and abundant sources of renewable energy on thisplanet. The human kind has used it for centuries as there are estimates that people were using thistype of energy as far as 4,000 years ago. In the year 1700, it was employed by the king ofBabylon for irrigation purposes (Ackermann & Kuwahata, 2013). The wind was also forgrinding grains by several farmers. It is also surprising to note that one of the earliest windmillshad the vertical axis of rotation. The people use braided mats or sails for rotating these windmillsacross the vertical axis. These windmills had an operational advantage as they were independentof the direction of the wind. The windmills using the horizontal axis of rotation are relativelynew as compared to vertical axis ones. The first documented proof of the existence of such millsdates back to 12th century. However, the ability to study the wind power across the horizontalaxis was the first to measure in the 20th century (Kuwahata et.al, 2013).The current status of wind energy is promising. The fourth edition of Global Wind EnergyOutlook claimed that the wind energy constitutes 3.5% of global electricity production. Theshare in power generation is estimated to reach 12% by the year 2020 (Kuwahata et.al, 2013). Atthe end of the year 2012, the total global production of the Wind Energy was 282 Giga Wattsshowing an increase of 44% from the year 2011 (Kuwahata et.al, 2013). The installation of windenergy had reached its peak during the year 2012, but after the same year, the total production ofwind power generation has decreased due to several reasons. In fact, the installation of windenergy for electricity generation falls to 18.7% which is the lowest in the past two decades.
The United States has also gained the global momentum, and the growth rate in thecountry was estimated to be around 27.9% during the year 2012. The total electricity produced inthe United States from wind energy was 140 terawatt-hours constituting the 3.5% of the totalenergy produced from entire sources (Armentrout & Armentrout, 2009). The US Department ofEnergy (DOE) has accelerated its efforts to install wind and water power generation capability ofthe country. The DOE also issues loans and guarantees to install wind electricity generation. TheDOE has estimated to supply 20% energy from the wind generation by the year 2030(Armentrout et.al, 2009).One of the primary reasons for the adoption of wind energy worldwide is the fact that it is ahighly environment-friendly source of energy. It is also estimated that in future conventionalsources of energy such as fossil fuels might run out. The world has to look for alternate sourcesof energy to meet the energy demands of the future generations (Crossley, 2000).The most important factor towards the adoption of the Wind Energy as energy productionsource as it is the cleanest forms of energy. The use of wind power as a source of power ensuresthat there is no emission of carbon dioxide and other harmful gasses into the atmosphere and thusit is safer to use as compared to fossil fuels and nuclear power stations. The main concern,however, is to increase the output and efficiency of wind energy generation keep the costs undercheck.The intended objective of this study is to develop an augmented wind device which canimprove the efficiency of the small-scale experimental wind turbines. Testing of the wind turbinewith the help of shroud and cone might facilitate in increasing the air flow to the turbine and thusincrease the overall efficiency. The performance of the device at various speeds and output
powers will be examined numerically and experimentally. The power output of the wind turbinewill be compared using shrouded wind turbine using cones with the turbines which are not usingthe cones.Literature Reviewa.Classification or Types of Wind TurbinesThe classification of the wind turbines is done on three main parameters. These parametersare:1.On the basis of orientation of axis of rotation(Crossley, 2000).2.The component of aerodynamic forces which are responsible for its rotation(Crossley,2000).3.The basis of energy generation capability (small, medium or large)(Crossley, 2000).b.Vertical Axis Vs Horizontal Axis TurbinesThere are mainly two kinds of wind turbines when they are classified on the basis of axis ofrotation. As their name suggests, the vertical type of the wind mills rotate perpendicular to theground while the horizontal type rotates parallel to the ground. Currently there are three populardesigns of wind mills(ERIKSSON, BERNHOFF, & LEIJON, 2008).1.Savonius VAWT.2.Curved Blade VAWT.3.Straight Blade VAWT.Svonius rotors typically have two or half drums attached to the central shaft in the oppositedirections. Curved blade VAWT consists of two or more curved blades attached to the central