Research On Navigation Safety Domain And Traffic Organization Of LNG Carrier In Port Waters

With the increasing demand for new energy in China,the number of LNG carriers arriving in ports will increase dramatically,and the traffic conflicts between LNG carriers and other vessels will become more prominent,which puts forward higher requirements for the navigation safety and efficiency in port waters.In the aspect of safety maintenance of LNG carrier entering and leaving port navigation,our country and abroad are generally used to ensure the safety of LNG carrier by setting LNG carrier safety zone.However,there is no uniform standard for the setting of LNG carrier safety zone,the setting scale is relatively large and the current LNG carrier safety zone setting lacks adaptability to the actual navigation environment.In aspect of ensuring the navigation safety of LNG carrier in port waters,this paper puts forward the concept of LNG carrier navigation safety domain,and constructs the calculation model based on ship braking characteristics and navigation risk analysis.On the basis of the research in LNG carrier navigation safety domain,the paper focuses on the research of LNG carrier's entering and leaving port traffic organization in order to ensure the navigation order,improve the navigation efficiency and alleviate the contradiction between LNG carriers and other vessels in port waters,accordingly provides reference for LNG carrier traffic organization and navigation management in port waters.The main work of this paper includes:(1)Establishes an influencing factors analysis model in LNG carrier navigation safety domain by using fuzzy analytic hierarchy process and improved empirical mode decomposition method,and analyses the importance ranking of influencing factors,then extracts the significant influencing factors.(2)Based on the analysis of the influencing factors in navigation safety domain,combining LNG carrier's manoeuvring characteristics,the paper establishes the calculation model of LNG carrier longitudinal safety domain by ship braking distance calculation model and car-following theory model.(3)Based on LNG carrier navigation risk analysis,combining LNG carrier navigation accident probability calculation model and accident consequence hazard calculation model,the paper constructes LNG carrier navigation risk quantitative calculation model.On the basis of this model,a risk acceptability criteria is reasonably defined to determine the width of LNG carrier lateral safety domain.(4)In view of the specific contents of LNG carrier traffic organization,including the influence of LNG carrier on channel navigation,LNG carrier entering and leaving port traffic control,time window of safe operation,LNG carrier escort,and traffic organization model,a feasible LNG carrier navigation organization plan in port waters is obtained through simulation and theoretical calculation.And then taking Ningbo-Zhoushan Port as an example,the analysis and application are carried out.By analyzing the factors affecting LNG carrier navigation safety domain and navigation risks,the paper constructs the calculation model for LNG carrier navigation safety domain and studies the LNG carrier traffic organization in port waters.The results have academic value to enrich the theory and method of LNG carrier safety domain research,and have good guiding significance to the navigation organization and management of LNG carrier in port waters.