Numerical analysis on propulsive efficiency and pre-deformated optimization of a composite marine propeller

Abstract

The objectives of this paper are to numerically investigate the performance of a composite propeller through bidirectional FSI algorithm combining CFD and FEM, and to improve its propulsive efficiency by a pre-deformated method. Numerical results are presented for the composite propeller which has been modeled by unidirectionally stacking with glass-fiber reinforced composites. The propulsive efficiency of the composite and rigid propellers with different advance coefficients J has been compared. The results show that the efficiency of the composite propeller is obviously higher than that of the rigid propeller when J≤0.8, which is attributed to the decrease of pitch angle caused by the bend-twist coupling effects. But for the design condition J=0.851 and the cases with J 0.851, the efficiency of the composite propeller is significantly lower than that of the rigid propeller, which is because the angle of attack αcomposite is deviated from the optimal angle of attack αdesign more than that for the rigid case αrigid. Based on the optimization by the proposed pre-deformated method, the efficiency improvement of the composite propeller at the conditions with J≥0.851 could be obtained, and the composite material used in this work can meet the strength requirement of the designed propellers.