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  2. Wind speed - Wikipedia

    en.wikipedia.org/wiki/Wind_speed

    The reference wind pressure q is calculated using the equation q = ρv 2 / 2, where ρ is the air density and v is the wind speed. [ 19 ] Historically, wind speeds have been reported with a variety of averaging times (such as fastest mile, 3-second gust, 1-minute, and mean hourly) which designers may have to take into account.

  3. Wind profile power law - Wikipedia

    en.wikipedia.org/wiki/Wind_profile_power_law

    The wind profile power law relationship is = where is the wind speed (in metres per second) at height (in metres), and is the known wind speed at a reference height .The exponent is an empirically derived coefficient that varies dependent upon the stability of the atmosphere.

  4. Roughness length - Wikipedia

    en.wikipedia.org/wiki/Roughness_length

    Roughness length is a parameter of some vertical wind profile equations that model the horizontal mean wind speed near the ground. In the log wind profile, it is equivalent to the height at which the wind speed theoretically becomes zero in the absence of wind-slowing obstacles and under neutral conditions. In reality, the wind at this height ...

  5. Log wind profile - Wikipedia

    en.wikipedia.org/wiki/Log_wind_profile

    When estimating wind loads on structures the terrains may be described as suburban or dense urban, for which the ranges are typically 0.1-0.5 m and 1-5 m respectively. [2] In order to estimate the mean wind speed at one height based on that at another (), the formula would be rearranged, [2]

  6. Wind gradient - Wikipedia

    en.wikipedia.org/wiki/Wind_gradient

    In common usage, wind gradient, more specifically wind speed gradient [1] or wind velocity gradient, [2] or alternatively shear wind, [3] is the vertical component of the gradient of the mean horizontal wind speed in the lower atmosphere. [4] It is the rate of increase of wind strength with unit increase in height above ground level.

  7. Pressure-wind relationship calculations for tropical cyclones

    en.wikipedia.org/wiki/Pressure-wind_relationship...

    Knaff and Zehr (2007) came up with the following formula to relate wind and pressure, taking into account movement, size, and latitude: [5] = + ′ Where V srm is the max wind speed corrected for storm speed, phi is the latitude, and S is the size parameter. [5]

  8. Beaufort scale - Wikipedia

    en.wikipedia.org/wiki/Beaufort_scale

    where v is the equivalent wind speed at 10 metres above the sea surface and B is Beaufort scale number. For example, B = 9.5 is related to 24.5 m/s which is equal to the lower limit of "10 Beaufort". Using this formula the highest winds in hurricanes would be 23 in the scale.

  9. Betz's law - Wikipedia

    en.wikipedia.org/wiki/Betz's_law

    In high wind speed, where the turbine is operating at its rated power, the turbine rotates (pitches) its blades to lower C P to protect itself from damage. The power in the wind increases by a factor of 8 from 12.5 to 25 m/s, so C P must fall accordingly, getting as low as 0.06 for winds of 25 m/s.