To comply with restrictive regulations, wind turbine development teams must perform an in-depth noise and vibration analysis to master the overall noise profile a new design. Next to assessing the air-borne, broad-band noise form blade aerodynamics, they have to control the structure-borne noise induced by mechanical and electrical equipment due to the rotation of systems like the gearbox and the generator.
Combining test and simulation
Mastering the radiated noise that covers almost the entire audible spectrum is a highly complex task. To tackle this challenge, LMS offers an innovative approach that uniquely combines test-based techniques with simulation methods in a so-called hybrid engineering approach. This hybrid approach mixes test-based loads with virtual simulation models and updates simulation models with test-based information. It provides close insights into the root causes of wind turbine noise and suggets potential countermeasures to reduce radiated noise levels.
Predicting far-field wind turbine acoustics
To master the radiated noise from the early development stage onwards, the LMS approach allows the creation of an accurate vibro-acoustic simulation model of a full-scale wind turbine. The combines structural Finite Element, Acoustic Boundary Element and LMS’ patented Acoustic Transfer Vector modeling techniques. The resulting model enables the prediction of the far-field wind turbine acoustics with the required accuracy and efficiency.
Laboratory and operational testing
LMS provides measurement solutions and the consulting experience to perform complex testing campaigns on wind turbines in a short time. Testing campaigns can focus on updating and correlating a wind turbine simulation model, evaluating the acoustic performance of different turbine designs or troubleshooting noise issues on an existing installation. Modal testing can be applied to characterize principal systems and components like the blades, the hub, the rotor, the tower, the gearbox, the brake, the bedplate and the nacelle. LMS has an in-depth experience in deploying special wind turbine test set-ups with over 300 measurement signals to acquire deflection, vibration and acoustic responses. Other important parameters like the surface pressure on the blades can be measured in the same test run. Measurements on the inside and the outside of the turbine can be perfectly synchronized with measurements inside rotating parts and in the surroundings of the wind turbine
