The full-scale performance prediction of a general cargo ship with a retrofitted gate rudder system using CFD procedures

As the shipping industry strives to comply with the IMO target to reduce greenhouse gas emissions from international shipping by at least half by 2050 (compared with 2008), fuel efficiency is becoming increasingly important. The Gate Rudder System (GRS) is an innovative energy saving device (ESD) and manoeuvring technology that has exhibited enhanced performance and the reduction of fuel consumption when retrofitted on vessels operating in coastal regions. The aim of the GATERS project, which is funded by the EC EU H2020 programme (ID: 860337), is to demonstrate the retrofit application of the GRS on ships, particularly general cargo vessels, from a global perspective. The project includes Computational Fluid Dynamics (CFD) analyses for accurate prediction of the performance of the Gate Rudder System.This paper provides a description of the CFD simulations carried out by one of the partners, Naval Architectural Services (NAS), to predict the full-scale performance of the GRS and exploit its benefits in ship-scale conditions. A similar study was also carried out for model-scale conditions and the results published in conference proceedings at the AYOCOL 22, titled “The Performance Prediction and Energy Saving Evaluation for the Retrofit of a Gate Rudder System on a General Cargo Vessel using CFD Procedures”. This paper is a follow-up to that article and outlines the developments on the on-going study, more particularly, those focusing on the full-scale performance conditions including the verification and validation procedure. Furthermore, various measurement data sets were used to highlight the commonalities and differences between the extrapolated model scale and direct CFD results.