Abstract: Liquefied natural gas (LNG) becomes widely used in ship industry as it is a kind of green fuel. The thermal and physical parameters of the different LNG components are compared and calculated based on the design of a 210 000 ton dual fuel bulk carrier, such as their boiling point, density, heating value of evaporation, enthalpy, composition of evaporation gas, low heating value and methane number. The value and deviation range of the boil-off rate of the marine LNG fuel tank and the critical gas supply parameter of the dual fuel engine are quantitatively analyzed and calculated corresponding to the different LNG fuel compositions. Some reasonable suggestions are provided for the practical application of LNG as marine fuel.

Key words: LNG composition, LNG fuel tank, dual fuel engine, boil-off rate, low heating value, methane number

摘要： 液化天然气作为一种清洁燃料,在船舶的使用需求已越来越旺。该文结合21万吨双燃料散货船设计工作,通过对不同LNG组分的沸点、密度、蒸发热值、焓值、蒸发气成分、低热值及甲烷值等热物性参数进行对比计算研究,定量分析计算不同LNG燃料组分对应的船用LNG燃料舱蒸发率及双燃料发动机重要供气参数的数值及偏差范围,对LNG作为船用燃料的实际工程应用提出合理化建议。

关键词: LNG组分, LNG燃料舱, 双燃料发动机, 蒸发率, 低热值, 甲烷值