Spray Icing Simulation and Anti‑icing Optimization for Ship Intake Grilles in Cold Environments

This study addresses the issue of spray icing on the air intake grilles of ship power systems in cold maritime environments. Through numerical simulation methods， the influence of environmental parameters on icing characteristics is revealed， and an energy-efficient zoned electric heating anti-icing strategy is proposed. A three-dimensional grille model is constructed to systematically analyze the effects of environmental temperature （from -20 ℃ to -4 ℃）， droplet diameter （from 50 μm to 500 μm）， and liquid water content （from 0.5 g/m³ to 8 g/m³） on icing rates and blockage of the flow channel. The results indicate that low temperature and high liquid water content significantly exacerbate icing. Under the condition of an environmental temperature of -20 ℃， droplet diameter of 500 μm， and liquid water content of 8 g/m³， the flow channel blockage ratio reaches 30.95% within 10 min. Additionally， as droplet diameter increases， the droplet impingement and icing regions become more concentrated toward the leading edge of blades. To mitigate grille icing in cold environments， an electric heating film configuration is employed for thermal protection. Optimization of the heating strategy reveals that the zoned heating approach， compared to the initial uniform heating scheme， effectively homogenizes surface temperature distribution while reducing total power consumption by 37.47%. This study validates the engineering applicability of the zoned electric heating anti/de-icing strategy， providing theoretical and technical support for the design of anti-icing systems in ship power systems operating in cold maritime regions.