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  2. Campbell diagram - Wikipedia

    en.wikipedia.org/wiki/Campbell_diagram

    Another critical speed at mode 4 is observed at 7810 rpm (130 Hz) in dangerous vicinity of nominal shaft speed, but it has 30% damping - enough to safely ignore it. Analytically computed values of eigenfrequencies as a function of the shaft's rotation speed. This case is also called "whirl speed map". [4] Such a chart can be used in turbine design.

  3. Environmental impact of wind power - Wikipedia

    en.wikipedia.org/wiki/Environmental_impact_of...

    Loud or persistent noise increases stress which could then lead to diseases, [175] and wind turbines do generate noise, though at typical setback distances, it is extremely low. For example, at a distance of 300 metres (980 ft) the sound generated may be around 45 dB; however, at a distance of 1.5 km (1 mi), most wind turbines become inaudible.

  4. Vertical-axis wind turbine - Wikipedia

    en.wikipedia.org/wiki/Vertical-axis_wind_turbine

    The world's tallest vertical-axis wind turbine, in Cap-Chat, Quebec Vortexis schematic Vertical axis wind turbine offshore. A vertical-axis wind turbine (VAWT) is a type of wind turbine where the main rotor shaft is set transverse to the wind while the main components are located at the base of the turbine. This arrangement allows the generator ...

  5. Passive ventilation - Wikipedia

    en.wikipedia.org/wiki/Passive_ventilation

    A roof turbine ventilator, colloquially known as a 'Whirly Bird' is an application of wind driven ventilation. Passive ventilation is the process of supplying air to and removing air from an indoor space without using mechanical systems.

  6. IEC 61400 - Wikipedia

    en.wikipedia.org/wiki/IEC_61400

    Turbine wind class is just one of the factors needing consideration during the complex process of planning a wind power plant. Wind classes determine which turbine is suitable for the normal wind conditions of a particular site. Turbine classes are determined by three parameters - the average wind speed, extreme 50-year gust, and turbulence. [12]

  7. Stack effect - Wikipedia

    en.wikipedia.org/wiki/Stack_effect

    [10] [11] The equations apply only to buildings where air is both inside and outside the buildings. For buildings with one or two floors, h is the height of the building. For multi-floor, high-rise buildings, h is the distance from the openings at the neutral pressure level (NPL) of the building to either the topmost openings or the lowest ...

  8. Robin hushed: wind turbines are making songbirds change ... - AOL

    www.aol.com/news/robin-hushed-wind-turbines...

    Robins are a much loved Christmas icon, but wind turbines installed in their habitat are affecting their song, with worrying consequences. Robin hushed: wind turbines are making songbirds change ...

  9. Variable speed wind turbine - Wikipedia

    en.wikipedia.org/wiki/Variable_speed_wind_turbine

    A variable speed wind turbine is one which is specifically designed to operate over a wide range of rotor speeds. It is in direct contrast to fixed speed wind turbine where the rotor speed is approximately constant. The reason to vary the rotor speed is to capture the maximum aerodynamic power in the wind, as the wind speed varies.