Lloyd’s Register (LR) has assessed Fistuca’s BLUE Hammer technology showing that it has the potential to produce “far less” underwater noise during the installation of offshore wind foundations compared to hydraulic hammers.
Fistuca’s BLUE Hammer technology uses the acceleration of a water column by combustion of a gas mixture to drive the pile into the ground. A combustion cycle pushes the water column in the air after which it falls back on the pile, delivering a second blow. This cycle is repeated until the pile reaches the desired depth.
The LR team assessed and combined scaled input test data and pressure calculations, with an adapted vibroacoustic model, and performed numerical simulations of the expected underwater noise from the prototype device during operation.
LR believes that the model is not only a prediction tool which will continue improving as the client gathers more offshore data, but also has tremendous relevance for the utility companies Fistuca is seeking to work with, as they need to have a high degree of confidence in underwater noise propagation predictions.
“We achieved valuable data from our reduced scale measurements and pressure calculations. The LR team was then able to combine the lab and calculation data with a carefully adapted vibro-acoustic model. This has become a very valuable prediction tool for us,” said Jasper Winkes , Fistuca’s Founder and Director.
The results comply with a study conducted by Dutch research institute TNO in March 2016, who measured underwater noise levels during Fistuca’s pile driving trials on a testpile and demonstrated that the BLUE Hammer device can achieve very low noise levels.
In April this year, Spain-based euskalforging manufactured and delivered five rolled rings for the BLUE 25M hammer which, once built, will be able to drive the largest offshore wind monopiles in the industry.