液化天然气动力船冷能梯级利用系统性能研究

Research on Performance of Cascade Utilization System of Cold Energy for LNG Powered Vessel

为高效合理地利用液化天然气(LNG)动力船上LNG气化释放的冷能,本文以某超大型油船为例,构建了一种发电与制冷相结合的冷能梯级利用系统。本文以甲烷和乙烷的混合物(质量比为50︰50)为发电工质、以R410A和R134a分别为冷库工质和空调工质,设计了该系统的工艺参数,对该系统进行热力性能计算。结果表明,LNG作为船舶动力燃料时,其冷量梯级回收方案可行。在满足船舶制冷需求的基础上,利用Rankine发电循环可回收约102.6 k W电量,LNG梯级利用系统的冷?效率为54.43%。

In order to get efficient and rational use of liquified natural gas(LNG)cold energy released during LNGvaporization on LNG powered vessel,a cascade utilization system combined power generation and refrigerationbased on a LNG powered Very Large Crude Carrier was presented.With a binary mixture of the methane-to-ethanemass ratio of50?50as the electrical working fluid,R410A as the cold working fluid and R134a as the airconditioning refrigerant,the parameters of the system are settled,and thermal performance is also calculated.Theresults show the possibility of the cold energy cascade recycling programs when LNG as a vessel fuel power.Thesystem not only meets the cold energy requirements of the vessel but also generates approximately102.6kW powerby Rankine cycle,and the exergy efficiency of the LNG cascade utilization in the system is54.43%.