Researches in this direction can reveal the influence mechanism of marine conditions on the passive safety system and key equipment of nuclear power.Researchers try to understand the operation characteristics of passive safety system of nuclear power under marine conditions and master the measures to restrain the influence of marine conditions, and solve the problems of the application of passive safety system and key devices in marine conditions. These researches have been applied to the design and optimization of passive safety system of CGN ACPR50S floating reactor, which improves the system safety. At the same time, the precise measurement of unsteady-state thermal performance of core fuel assembly is realized, and the influence mechanism of complex factors such as ocean conditions on the core thermal-hydraulic behavior is revealed, and the problem of the lack of key thermal-hydraulic models suitable for the reactor core under unsteady-state conditions such as ocean conditions is solved.