The increasing popularity of polar shipping routes poses greater challenge to the marine cold protection technology. Considering the importance of the cold-proof design of the sea chest, the key requirements of the sea chest in the ice region in the relevant specifications of the classification society are introduced in order to ensure the stable operation of the ship in polar environment. The current cold protection technologies are classified and analyzed from the structural design, structural layout and auxiliary deicing according to the principles of different cold protection technologies. The application of the cold protection measures based on different technical principles in different design schemes are highlighted by comparing the characteristics of four cold protection design schemes. The unique technical key points of the cold protection design of the sea chest in the ice region are summarized. It can provide ideas for promoting the scientificity and rationality of the cold protection technology of the sea chest in the ice region in subsequent researches.

The influence of the side wall effect on the ship motion should be taken into account to predict the motion of the ship in the restricted waters, such as a narrow channel or a canal. The side wall effect has been considered by introducing the green function of channel free surface. The green function of the side wall with free surface is then approached by Chebyshev polynomial to perform the efficient and high accurate calculations. The results calculated in the current study are compared with which is calculated by the commercial software. The artificial numerical damping is adopted for the free surface in order to address the numerical resonance phenomenon of the free surface during the numerical calculation, ensuring that the motion of the floating body and the calculated elevation of the free surface are more accordant with the actual conditions.

In view of the increasingly strict environmental protection requirements, more and more transport ships have installed Selective Catalytic Reduction (SCR) systems which meet the Tier III emission standards. This paper describes the application of SCR system on the ship, sorts out the requirements of the relevant rules for the urea tank in the SCR system, and compares the schemes of the urea tank arranged in different positions. It can provide reference for the further design and arrangement of the urea tank.