Computation of Hydrodynamic Characteristics of A Marine Propeller Using Induction Factor Method Based on Normal Induced Velocity

In this study, induced velocity is determined with accuracy by overcoming the assumption of the vortex theory in calculating the induced velocity. The characteristics of a two bladed propeller are determined based on this velocity. The dominant parameters for the determination of the propeller characteristics are blade pitch angle, chord/diameter ratio, value of advance coefficient, position of blade sections and number of blades. The induction factor,the ratio of nomal induced velocities for helical and straight vortex respectively,is calculated to determin the normal induced velocity and then other characteristics. By keeping the values of propeller pitch and diameter constant with the filament of trailing vortices which produce helical surfaces extending infinitely backwards,the characteristics of propeller like lift coefficient, drag coefficient, thrust coefficient, torque coefficient and efficiency are derived for various blade sections and the values are compared with other experimental results.