Ice-Class Propeller Strength and Integrity Evaluation Using Unified Polar ClassURI3 Rules

Abstract

A systematic method was developed for ice-class propeller modeling, performance estimation, strength and integrity evaluation and optimization. To estimate the impact of sea ice on the propeller structure, URI3 rules, established by the International Association of Classification Societies in 2007, were applied for ice loading calculations. An R-class propeller (a type of ice-class propeller) was utilized for subsequent investigations. The propeller modeling was simplified based on a conventional method, which expedited the model building process. The propeller performance was simulated using the computational fluid dynamics (CFD) method. The simulation results were validated by comparison with experimental data. Furthermore, the hydrodynamic pressure was transferred into a finite element analysis (FEA) module for strength assessment of ice-class propellers. According to URI3 rules, the ice loading was estimated based on different polar classes and working cases. Then, the FEA method was utilized to evaluate the propeller strength. The validation showed that the simulation results accorded with recent research results. Finally, an improved optimization method was developed to save the propeller constituent materials. The optimized propeller example had a minimum safety factor of 1.55, satisfying the safety factor requirement of ≥1.5, and reduced the design volume to 88.2% of the original.