Damen Shipyards Group has carried out tank testing of its 70-metre Fast Crew Supplier (FCS) 7011. The tests were carried out at the Delft University of Technology (TU Delft) with a 2.8-metre long model. Intended for long distance crew transfer operations, the Damen FCS 7011 will offer the offshore oil & gas industry a safe and cost-effective alternative to helicopter flights.
In developing the FCS 7011, on-board comfort has been one of Damen’s central design parameters. Consequently, the company has executed a large number of simulations to investigate seakeeping characteristics.
"We have used these simulations to see which hull form gives the optimum comfort levels," explains Albert Rijkens, Damen Product Portfolio Manager Research. "The aim of the model testing at TU Delft was to validate those numerical results."
Performing tests at 30 knots and 40 knots in waves of 2-3 metres significant wave height, seakeeping was a major aspect of the testing. The results were positive; the hull design and the application of the Sea Axe bow allows the vessel to reach high speeds through waves while meeting predetermined criteria for comfort levels.
"In fact, what we see is that ship movements become calmer as the speed increases. This is because the forward energy of the vessel allows it to go through the waves, instead of going over them. At the same time the Sea Axe bow shape reduces any uncomfortable slamming that might occur during high speed transits."
Another aspect of the tank testing was to study vessel resistance at speed. "Our results showed that, due to its long and narrow hull, the FCS 7011 has relatively low resistance."
The tests were also an opportune moment to trial the so-called Ride Control System positioned at the stern of the 1:25 scale model of the FCS 7011. "This system measures ship movements and based on these signals it continuously determines the position of the active control mechanisms. The effectiveness of the system – enabling us to improve comfort levels even further – was also validated in these tests."
