Research On Key Technology Of Scheme Design Of Liquified Natural Gas Bunker Vessel

With the continuous increase of global environmental pollution,the use of clean energyand transport issues have received increasing attention.As an ideal clean energy source,liquefied natural gas is used more and more widely,and LNG trade is becoming a new hot spot in the global energy market.With the increase of LNG-powered ships,the technology,methods,facilities and equipments for adding LNG fuel to them have become a prominent issue for the shipbuilding industry and the shipping industry.LNG bunker vessels have become an important development direction of LNG filling technology because of its advantages of self-navigation capability,safety,reliability and flexible dispatching.The development of this type of ship and the study and formulation of relevant standards will help the convergence and improvement of the entire LNG industrial chain,and it is also an important embodiment of the implementation of Chinese energy-saving emission reduction strategy.This has strong practical significance.On the basis of summarizing previous studies,this article further deepens the study of some key technologies in the design process of LNG bunker vessels,providing theoretical and technical support for future generations to design and study the work of LNG bunker vessels.In this paper,research on key technology of scheme design of liquified natural gas bunker vessel is regarded as the topic.The paper will study from the following three aspects,the overall design ideas of small LNG bunker vessel,steady-state thermal analysis method for the prediction of evaporation rate of cargo hold for LNG bunker vessel and evaluation technology of design scheme for LNG bunker vessel.The main work include the following points:1.Collect a large amount of literature and data to understand the research background,purpose and significance.Compare various LNG filling methods to understand the filling advantages of LNG bunkering vessels.Summarize the technical characteristics of LNG bunkering vessels.2.The design ideas for the small-scale LNG filling ship program were combed.Taking the design of a small-scale LNG filling ship of 1000m3 as an example,the relevant specifications and regulatory requirements for the filling capacity of small-sized LNG filling vessels,tank selection,and vessel type design were discussed.The basis for the determinationof the main scale and the related contents of the general layout design.It lays a foundation for the calculation of the evaporation rate and regular analysis of the LNG refueling ship cargo containment system and the establishment of an evaluation index system for the design proposal of the LNG refueling vessel.3.According to the characteristics of the cargo hold of LNG bunker vessel and the heat transfer analysis method of ANSYS software,the numerical prediction method of evaporation rate of the LNG bunker vessel at full load and how to correct the thickness of the insulating layer are explored.The relation between the evaporation rate of liquid tank and the thickness of insulating layer,the thermal conductivity of insulating layer and the heat convection coefficient are got.The numerical prediction method of evaporation rate of the LNG bunker vessel under different loading rates is explored.4.Based on the design and work characteristics of the LNG bunkering ship and the experience and conclusions of the inside and outside of the industry in recent years and the overall design of the ship,a design proposal evaluation index for the LNG bunkering ship is created.Choosing multi-objective decision-making as a general idea and action guidance,combined with qualitative and quantitative analysis of specific means,and extracting the central themes of analytic hierarchy process and fuzzy comprehensive evaluation way,use reformative fuzzy-level analysis method for LNG bunkering ship to choose a final design program.It is proved after assessment of the figure cases that the evaluation target system and evaluation way of the program are practical and feasible,and have good stability and accuracy.