液化天然气(LNG)冷能用于斯特林发动机和燃气轮机的联合系统研究

A Combined System of Stirling Engine and Gas Turbine Based on LNG Cold Energy

利用LNG冷能具有较好的节能潜力和经济效益,通过流程的创新设计,提出了一种将LNG冷能用于燃气轮机和斯特林发动机的联合系统。基于热力学第一、第二定律,对联合系统进行热力学分析,结果表明:在环境温度35℃条件下,联合系统的输出功率为5715.48kW,热效率为31.62%,效率为43.65%;相比燃气轮机系统和直接冷却进气系统,联合系统的输出功率分别提高了7.84%和0.78%,热效率分别提高了3.16%和1.18%,效率分别提高了4.23%和1.63%。联合系统在不同环境温度下,可将燃气轮机的进气温度降低10℃左右,系统的输出功率和效率随着进气温度的降低均有所提高。

Utilizing cold energy of LNG would bring good economic benefits.A combined system of Stirling engine and gas turbine for recovering LNG cold energy is put forward.Based on the first and second laws of thermodynamics,the combined system is analyzed in detail.The results show that in the 35℃ environment,the output power of combined system is 5715.48kW,the thermal efficiency is 31.62%,and the exergy efficiency is 43.65%.Compared with the gas turbine system and the direct cooling inlet air system,the output power of combined system will respectively increase 7.84% and 0.78%,the thermal efficiency will increase 3.16% and 1.63%,and the exergy efficiency will increase 4.23% and 1.63%.At different environment temperatures,the inlet air temperature will decrease about 10℃ in the combined system,and the output power and efficiencies will increase with the decreasing of inlet air temperature.