Rotor sensor
The rotor sensor can be added by toggling on the Sensor button in the Rotor part shown in the following picture:
For multi-rotor wind turbines, a sensor is available for each rotor
The Rotor sensor provides the following fields:
Field | Unit | Description |
Power (aero) | kW | aerodynamic power, i.e. the power exerted by the air on the blades |
Torque (aero) | kNm | aerodynamic torque, i.e. the moment around the main shaft axis resulting from the aerodynamic forces on the blades |
Thrust (aero) | kN | total aerodynamic force on the rotor in the main shaft direction |
RPM | 1/m | revolutions per minute of the rotor, number of revolutions the turbine does in one minute. Also called Rotational speed or Rotational velocity |
TSR | - | Tip speed ratio, ratio of the velocity of the tip of a blade over the wind speed magnitude at the hub |
Pitch angle | degrees | angle by which the blades are rotated around the pitch axis. The pitch axis corresponds to the longitudinal axis if the blades are not prebend |
Power coefficient (Cp) | - | ratio of the aerodynamic power over the total available power in the air (see CP - Power coefficient) |
Thrust coefficient (Ct) | - | ratio of the thrust force over the dynamic force |
Tip speed | m.s-1 | velocity of the tip of the blades. Calculated based on the RPM and the blade length |
1P (one revolution) | s | time it tales for the rotor to complete one revolution. Calculated by taking the inverse of the RPM and multiplying by 60 |
nP (blade passing) | s | time it takes for a blade to pass in front of the tower. Calculated by dividing 1P by the number of blades |
Azimuth angle | degrees | angular position of the rotor. An azimuth angle of 0 means that the blade 0 is pointing upwards |
Rotation per timestep | degreed | degrees the rotor has rotated in one time step. The time step can be changed in the Analysis parameters |
Wind speed at hub, magnitude | m.s-1 | magnitude of the wind speed at the hub location |
Wind speed at hub | m.s-1 | components of the wind speed at the hub location. The components are given in the global coordinate system (see Coordinate systems) |