Verifying performance and safety requires accurate representation of a ship and its ride control elements in relevant wave conditions. Our Seakeeping and Manoeuvring Basin (170 x 40 m) is designed for making arbitrary (high-speed) manoeuvres in realistic waves from arbitrary directions. The free-sailing or captive tests provide insight into the seakeeping and manoeuvring characteristics.
The carriage with a maximum speed of 6 m/s runs over the total length of the tank. It consists of a mainframe, spanning the full width of the basin, and a sub frame with a max. speed of 4 m/s along the mainframe. The carriage can follow all movements of the model in the horizontal plane. With an extra installed turntable, the system has a rotating arm capability.
Waves & wind
At two adjacent sides of the basin, segmented wave generators consisting of hinged flaps are installed. Each flap is controlled separately by a driving motor and has a width of 60 cm. The capacity of the wave generator is up to a significant wave height of 0.45 m at a peak period of 2 seconds. Opposite the wave generator, passive sinkable wave absorbers are installed. The wave generator system is equipped with an active wave reflection compensation feature and higher order wave synthesis techniques.
Wind can be simulated by an adjustable 10 m wide platform with electrical fans.
Motion Control and Dynamic Tracking
Free running tests are performed such that the model follows an arbitrary pre-defined track (straight or curved) through the basin. The carriage follows the model during this task. Deviations from the pre-defined track are minimised through a dynamic positioning feedback loop which controls the propulsion units, additional thrusters and steering within a particular control scenario. Motion control is realised by means of a feedback loop which activates related stabilisation systems (fins, foils, rudders, etc).
Model size range
Models tested in the Seakeeping & Manoeuvring Basin vary from moving objects with a model length of 2 - 8 m, moored objects up to 10 m and floating structures of any kind, size depending on water depth and wave conditions.
Seakeeping tests in waves and wind from arbitrary direction
Resistance and self propulsion tests in calm water and waves
Oscillation (PMM) and rotating arm tests in calm water and waves with a restrained model to determine hydrodynamic coefficients
Captive or free sailing manoeuvring tests in calm water and waves
Installation and sea transport tests of offshore constructions
Tests on moored or fixed objects to determine motions and loads due to waves and wind.