THEORETICAL EVALUATION OF WAKE INCREASING NOZZLE

摘要

As an energy saving device, we propose "Wake Increasing Nozzle (WIN)" to improve propulsive performance of ship. The shape of WIN is similar to a duct, but its purpose is to decrease the flow velocity inside the nozzle and to increase the propeller thrust. By adopting two kinds of WINs (-A and -B), we obtain flow and drag characteristics of the nozzle itself and the nozzle interacting with a propeller and the nozzle fitted to a tanker model making use of the boundary element methods and then calculate the propulsive performances of the tanker model and the virtual full-scale ship. We show the effectiveness of WIN by theoretical evaluation.