Ships are prone to icing when navigating in polar low-temperature environments. Excessive ice accumulation can affect ship stability, operational safety, and operability of deck equipment, posing a serious threat to crew safety and hindering the rational development and utilization of polar regions. Ship icing is mainly caused by the splashing of waves, and its physical process can be regarded as the freezing process of a large number of saltwater droplets on a cold surface. Experimental research on the freezing process of a single saltwater droplet is essential for deeper understanding of the mechanism of ship superstructure icing at the mesoscale. For this, experiments are conducted on the freezing and melting of freshwater droplets on cold surfaces, the progress of the phase interface during the freezing process of freshwater droplets, the shape changes of water droplets after freezing, the freezing and melting time are recorded, and the influencing factors of the freezing process of freshwater droplets are analyzed. A saltwater droplet freezing experiment with a 3.5% mass fraction is also conducted, the shape changes, freezing and melting times after freezing are recorded, and the impact of droplet volume and cold surface temperature on the freezing process of the saltwater droplets are analyzed and discussed. The influence of salinity is analyzed and compared by comparing the freezing and melting experimental results of saltwater with those of freshwater droplets. The research outcome can provide data support for the validation of ship icing prediction models and scientific guidance for the development of anti-icing and deicing technologies on structural surfaces.

Polar navigation is the guarantee for ships to achieve scientific research and safe navigation in the polar area. At present, there are many studies on the theory of polar navigation in China about the arrangement of Inertial Navigation System (INS), the availability of satellite navigation polar area, multi-sensor integrated navigation, etc. But there are still blanks in the application of polar navigation and ice exploration equipment in the high latitude navigation engineering in the polar area. In order to solve the engineering application problems of the device in the polar region from the system level, the paper combines the theory to analyze the polar environment and ship based in the polar region on the performance of the navigation device, and combines the research status of the ice exploration radar, inertial navigation, satellite navigation, electronic charts, satellite communication and other devices in the polar region, studies the working process of the design of the ice navigation device, and discusses the direction of future research and development of the navigation device in China.

Since 1980s, China has begun to study sea ice in the polar regions, and more accumulation has been made in the natural science of the sea ice than in the relevant engineering application. The engineering properties of the sea ice are of great concern with the increasing value of polar shipping. The physical and mechanical properties are important engineering properties of the sea ice, which determine the rational design and safe operation of the ice engineering. The three-point bending tests under different temperatures are conducted in the low-temperature laboratory to measure the sea ice flexural strength and effective elastic modulus by using the complete ice block that was extracted through the whole ice thickness of the landfast sea ice in the Prydz Bay during the 36th Chinese National Antarctic Research Expedition. The flexural strength and effective elastic modulus are correlated to the sea ice porosity. The lower envelope of the flexural strength and the upper envelope of the effective elastic modulus are used to estimate the bearing capacity of the landfast ice in the Prydz Bay, Antarctica. It can provide a safety guarantee for the unloading on ice in Antarctica. By using the physical properties of the sea ice, the mechanical properties of the sea ice are obtained to design the bearing capacity of the ice layer, which gives a new insight on the ice engineering.