Case study

Kooiman Marine Group, NL

Ducted propellers design for multipurpose vessel “Zwerver I”

Customer: Kooiman Marine Group, NL
Related services: Ship resistance & powering prediction, CFD simulation, adapted propeller design & supply
Scope of work

  • 3D model of the hull
  • Hull analysis by CFD tools
  • Nominal wake calculation
  • Self-propulsion computation
  • Propeller geometry design, adapted to vessel operational profile
  • Supply of propellers compatible with existing shafts

This vessel was originally fitted with 2 azimuthal propellers, to which 2 additional shaft lines were added, retrofitted by Gebr. Kooiman shipyard; each of these lines consist of a FP propeller driven by a diesel engine Mitsubishi S12R-MPTAW of 940kW at 1600 rpm, coupled to a Reintjes gearbox WAF665 5.950:1.
Propeller design has been done in order to minimize cavitation in the bollard pull condition by adapting sections and pitch distribution, moderately increased area and enough rake backwards to center tip propeller on nozzle. In addition, other service conditions (running at 6 and 9 knots) were also studied.
5-blade propellers with a diameter of 2000mm had been supplied with this optimized design.
According to the shipowner, Van Stee Offshore, during DP-trials and commissioning the vessel, equipped with 8 thrusters in total, showed her capability with astonishing results in different configurations.
For further details of this vessel, you can watch this video.