Wind Turbulence

Notation

c_o(z) = Orography factor
I_v(z) = Turbulence intensity
k_l = Turbulence factor
k_r = Terrain factor depending on the roughness length
v_b = Basic wind velocity
v_m(z) = The mean wind velocity
z_min = Minimum height
z_o = Roughness length
σ_v = Standard deviation of the turbulence

The turbulence intensity I_v(z) at height z is defined as the standard deviation of the turbulence divided by the mean wind velocity. The turbulence intensity I_v(z) is calculated using equation below.

The standard deviation of the turbulence σ_v is calculated using equation below.

Terrain factor k_r and basic wind velocity, v_b are defined in the Mean Wind title.

Turbulence factor k_l may be given in the National Annex. The recommended value for k_l is 1,0.

Orography factor c_o(z) is defined by user.

Roughness length z_o is given in EN 1991-1-4 Table 4.1.