Numerical analysis of propeller exciting force in oblique flow

Abstract

CFD commercial software FLUENT, based on solving RANS equations, was used to calculate propeller hydrodynamic performance and exciting force. Sliding grid technique was applied to simulate the propeller rotation. Different advance coefficients and oblique inflow angles were set as different working conditions through adjusting inflow magnitude and direction. DTMB4679 propeller as the research object, hydrodynamic performance of this propeller in oblique flow was first calculated, and agreed well with test results. It verifies the accuracy of calculation method. The time-domain data of propeller exciting force under different working conditions was monitored, and then spectrum curve was obtained through fast Fourier transform. The results show that propeller load in oblique flow will aggravate, and transverse velocity component of oblique flow will cause great transverse force generated by propeller. Moreover, the smaller advance coefficient causes the greater peak of propeller fluctuating pressure. Additionally, oblique flow angle has a greater influence on unsteady bearing force than fluctuating pressure.