Linear wind

The Linear wind can be selected in the Atmosphere part. A linear wind is defined by the following parameters:
  • Start speed 

  • End speed 
  • Start-up duration 

  • Duration 
The role of these parameters is illustrated in the following figure:

The magnitude of the wind speed at the hub 
 is defined as follows:
$$V_{hub}=\left\{\begin{array}{lll} V_0&\text{for}&t{<}T_0\\V_0+ (t-T_0)\cdot\frac{V_e-V_0}{T}&\text{for}&T_0\leq t {<} T_e\\ V_e&\text{for}&t\geq T_e\\  \end{array}\right.$$

The same equation applied for the Wind angle 
, replacing the start speed 
 and the end speed 
 with the start angle 
 and the end angle 
, respectively:
$$\alpha=\left\{\begin{array}{lll} \alpha_0&\text{for}&t{<}T_0\\\alpha_0+ (t-T_0)\cdot\frac{\alpha_e-\alpha_0}{T}&\text{for}&T_0\leq t {<} T_e\\ \alpha_e&\text{for}&t\geq T_e\\ \end{array}\right.$$