Numerical investigation into the effect of incidence flow angles on submarine propeller hydrodynamic characteristics

This study uses Computational Fluid Dynamics (CFD) to investigate the forces and moments acting on a generic submarine propeller at various inflow angles. The propeller is examined in both Open Water Condition (OWC) and Behind Hull Condition (BHC). For the latter, a fully appended BB2 generic submarine hull is used representing a typical conventional (SSK) submarine.The results for both the OWC and BHC show that the propeller thrust and torque vary significantly with angles of incidence; the BHC having the greatest variation. A greater inflow angle produces more noticeable in-plane loads on the propeller, which will cause a moment that acts to reduce the drift angle of the vessel during manoeuvres.This work contributes to the understanding of the effect of inflow angles on the propulsion properties of submarine propellers and the development of representative body forcepropellers. The latter are often used in place of rotating propellers for CFD based free running submarine manoeuvring simulations, thus significantly reducing computational cost