Method and device for monitoring the dynamic behavior of a rotating shaft, in particular of a gas or steam turbine

A device for monitoring a vibration behavior in a rotatable machine, comprising:

• a shaft rotatably supported;
• a plurality of sensors arranged at a defined spatial position outside the shaft where the plurality of sensors measure rotor vibration and provide measured values of the rotor vibration;
• and
• a computation unit connected to the plurality of sensors that receives the measured values of the rotor vibration and computes the vibration behavior of the rotor in at least one preferred direction that is different from the spatial positions of the sensors wherein the vibration behavior of two different preferred directions are determined and wherein said two preferred directions coincide with main stiffness axes of the machine.

A turbine, comprising:

• a rotational rotor arranged along a rotational axis of the turbine;
• a stationary stator arranged coaxially and at least partially surrounding the rotor;
• a plurality of sensors arranged at a defined spatial position outside the rotor where the plurality of sensors measure vibration of the rotor and provide measured values of the rotor vibration;
• and
• a computation unit connected to the plurality of sensors that receives the measured values of the rotor vibration and computes the vibration behavior of the rotor in at least one preferred direction that is different from the spatial positions of the sensors wherein the vibration behavior of two different preferred directions are determined and wherein said two preferred directions coincide with main stiffness axes of the machine.