A Project Report on Vertical Wind Turbine Prepared by Abhishek Aggarwal Ujjwal Kumar Niraj Kumar Under the guidance ofAjay Kumar Department of Mechanical Engineering, Laxmi Devi Institute of Engineering & Technology, Chikani, Alwar Session: 2010-2011
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A windmill is an engine powered by the wind to produceenergy. It is a device that converts kinetic energy from thewind into mechanical energy. If the mechanical energy isused to produce electricity, the device may be called a windgenerator or wind charger. If the mechanical energy isused to drive machinery, such as for grinding grain orpumping water, the device is called a windmill or wind
pump. Developed for over a millennium, today's windturbines are manufactured in a range of vertical andhorizontal axis types. The smallest turbines are used forapplications such as battery charging or auxiliary power onsailing boats; while large grid-connected arrays of turbinesare becoming an increasingly large source of commercialelectric power.
• Windmills were used in Persia (present-day Iran) as early as 200 B.C..
• The first known practical windmills were built in Sistan, a region between Afghanistan andIran, from the 7th century. These “Panemore” were vertical axle windmills, which had longvertical drive shafts with rectangular blades.
• Windmills first appeared in Europe during the middle ages. The first historical records fortheir use in England date to the 11th or 12th centuries and there are reports of German crusaders taking their windmill-making skills to Syria around 1190.
• By the 14th century, Dutch windmills were in use to drain areas of the Rhine delta. • First electricity generating wind turbine, was a battery charging machine installed in July1887 by Scottish academic.
• In Denmark by 1900, there were about 2500 windmills for mechanical loads such aspumps and mills, producing an estimated combined peak power of about 30 MW. The largest
machines were on 24-metre (79 ft) towers with four-bladed 23-metre (75 ft) diameterrotors. By 1908 there were 72 wind-driven electric generators operating in the US from5 kW to 25 kW.
• In the fall of 1941, the first megawatt-class wind turbine was synchronized to a utility gridin Vermont. The Smith-Putnam wind turbine only ran for 1,100 hours before suffering acritical failure. The unit was not repaired because of shortage of materials during the war.
• The first utility grid-connected wind turbine to operate in the U.K. was built by John Brown& Company in 1951.
A quantitative measure of the wind energy available at any location is calledthe Wind Power Density (WPD) It is a calculation of the mean annual poweravailable per square meter of swept area of a turbine, and is tabulated fordifferent heights above ground. Calculation of wind power density includes theeffect of wind velocity and air density. Color-coded maps are prepared for aparticular area described, for example, as "Mean Annual Power Density at 50Meters.
Betz Limit
All wind power cannot be captured by rotor or air would be completely still behindrotor and not allow more wind to pass through. Theoretical limit of rotor efficiencyis 59%.
Vertical Axis Turbine• Vertical-Axis Wind Turbines (or VAWTs) have the main rotor shaft arranged
vertically.
• Key advantages of this arrangement are that the turbine does not need to bepointed into the wind to be effective. This is an advantage on sites where thewind direction is highly variable, for example when integrated into buildings.
• The key disadvantages include:• The low rotational speed with the consequential higher torque and
hence higher cost of the drive train,• The inherently lower power coefficient, the 360 degree rotation of
the aerofoil within the wind flow during each cycle and hence thehighly dynamic loading on the blade,
• The pulsating torque generated by some rotor designs on the drivetrain, and the difficulty of modelling the wind flow accurately.
With a vertical axis, the generator and gearbox can be placed
near the ground, hence avoiding the need of a tower andimproving accessibility for maintenance. Drawbacks of thisconfiguration include(i) wind speeds are lower close to the ground, so less wind
energy is available for a given size turbine, and(ii) wind shear is more severe close to the ground, so the rotor
Even with an advanced or optimistic realization in 2020, GWEC is projectingonly an 18% share of electricity for wind energy in India, requiring 134 GWof wind power capacity.
Comparison of Global and India Wind EnergyScenario
Wind maps: Mean (annual andseasonal) wind speed andpower density at 50m and80m.
Verification: Can compare
generalized wind climatesderived from observationalwind atlas method andnumerical wind atlasmethod.
Application data: Generalizedwind climate in WAsP .libfile format for all of India;50 from observational windatlas and 200,000+ fromnumerical wind atlas, allowsapplication at very high
Inexpensive, reliable, simple, the hallmarks of the Helix system make it thebest choice for low wind speed residential and commercial applications. TheSavonius turbine based design catches wind from all directions creatingsmooth powerful torque to spin the electric generator. Mounted up to 35 feethigh, in winds as low as 10 mph the Helix system creates electricity to poweryour home or business.