Numerical Study on the Closed-Loop System of a Marine LNG Engine with Reformed Exhaust Gas Recirculation

Numerical Study on the Closed-Loop System of a Marine LNG Engine with Reformed Exhaust Gas Recirculation

Liquefied natural gas

Combustion

Volume fraction

Emission control

Gases

Brakes

Exhaust gas recirculation

GT-Power based closed-loop model of a liquefied natural gas(LNG)engine with a reformer was built to explore the effect of reformed exhaust gas recirculation(REGR) rate and n(the volume fraction ratio of CH4 to O2)on performances of the engine and the reformer. The results show that the H2 volume fraction in the reforming products decreases with the increase of REGR rate. When the n increases, the H2 volume fraction in the reformate increases. The cylinder peak pressure decreases with the increase of REGR rate, while the flame development period and the combustion duration increase. NOx emission decreases to meet IMO Tier emission limits when the REGR rate approaches 10%. Compared to traditional EGR mode, the cylinder peak pressure of the REGR mode is higher, and the flame development period and the combustion duration are shorter. In addition, the brake thermal efficiency(BTE)of the REGR mode is larger than that of the EGR model, while the brake specific fuel consumption(BSFC)and the HC emission reduce. The research results can provide a reference for regulation between the LNG engine and the REGR reformer to realize effective emission control. 2022, Editorial Office of the Transaction of CSICE. All right reserved.

29-37

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40

Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines)

2022

Tang, Ligang

Zhang, Zunhua

Long, Yanxiang

Li, Gesheng

journalArticle

10000909

10.16236/j.cnki.nrjxb.202201004