Author(s): Jinghan Su; Shifeng Ding; Fang Li; Pentti Kujala; Linlin He; Liangliang Lu; Li Zhou
Linked Author(s):
Keywords: Ice propeller; Propeller; Ice blockage; Cavitation; Tip vortex cavitation
Abstract: With the rapid expansion of Arctic shipping, marine propellers increasingly operate in ice-covered environments where blockage-induced inflow distortion promotes premature cavitation and intensifies unsteady hydrodynamic loading. Although blade number is a critical design parameter, its effect on cavitation under ice blockage conditions has not been systematically investigated. This study addresses the gap through unsteady Reynolds-averaged Navier–Stokes (URANS) simulations coupled with the Schnerr–Sauer cavitation model and SST k–ω turbulence closure. Propellers with four, five, and six blades are analyzed over advance coefficients J = 0.35–0.55 under identical blockage configurations; the method is validated against experimental data within 5% relative error. Results show that increasing blade number raises the thrust coefficient and torque coefficient while open-water efficiency remains nearly unchanged, as viscous losses and inter-blade interference offset the additional thrust. The four-bladed propeller exhibits the most extensive sheet cavitation and strongest tip-vortex cavitation; higher blade numbers redistribute per-blade loading but produce more complex, fragmented cavity structures due to intensified blade-to-blade interaction. The cavitation region between the propeller and the ice persists regardless of advance ratio, reflecting the sustained low-pressure zone created by blockage-induced acceleration. Wake field analysis reveals that increasing blade number progressively fragments the downstream high-velocity region and amplifies spatial non-uniformity. These findings demonstrate that blade-number effects on cavitation under ice blockage differ substantially from open-water trends, providing quantitative guidance for the hydrodynamic design of propellers intended for polar operations.
Year: 2026