Waterjet Propulsion and Negative Thrust Deduction

Paper in proceeding, 2015

The thrust deduction fraction of waterjet-propelled hulls is often reported to be negative in the speed range close to the operating speeds. In this paper, employing a numerical method, the bare hull and the self-propelled hull flows are studied. The changes between the bare hull and self- propelled hull resistances are investigated for understanding whether it is the waterjet hull resistance decrease which contributes to the negative thrust deduction fraction or there are some other effects rather than the resistance increment.