A comparative study of using diesel and PODEn as pilot fuels for natural gas dual-fuel combustion. (15th January 2017)

• Record Type: Journal Article
• Authors: Song, Heping; Liu, Changpeng; Li, Fubai; Wang, Zhi; He, Xin; Shuai, Shijin; Wang, Jianxin
• Is Part Of: Fuel. Volume 188(2017)
• Page Start: 418
• Page End: 426
• Publication Date: 2017-01-15
• Subjects: PODEn -- Natural gas -- Dual-fuel -- Low temperature combustion; PODEn polyoxymethylene dimethyl ethers -- THC total hydrocarbon -- DF dual-fuel -- CNG compressed nature gas -- SOI start of ignition -- SI spark ignition -- ATDC after top dead center -- LTHR low temperature heat release -- AHRR apparent heat release rate -- ITE indicated thermal efficiency -- IMEP indicated mean effective pressure -- HPDI high pressure direct injection -- LHV lower heating value -- LTC low temperature combustion -- CA crank angle -- EGR exhaust gas recirculation -- PPRR peak pressure rise rate -- EPA Environmental Protection Agency; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2016.10.051
• Languages: English
• ISSNs: 0016-2361

Abstract

Highlights: First study on PODEn /CNG dual-fuel combustion. Natural gas dual-fuel LTC reduced NOx emissions and improved efficiency. PODEn /CNG dual-fuel combustion lowered THC, CO, NOx and soot emissions. PODEn /CNG dual-fuel combustion achieved higher efficiency. Abstract: Compared to natural gas spark-ignition (SI) combustion, dual-fuel (DF) mode could achieve higher indicated thermal efficiency (ITE). The major disadvantages of natural gas DF combustion are rough combustion at high load, high CO and total hydrocarbon (THC) emissions, and low natural gas substitution rate. In the present work, a comparison of using polyoxymethylene dimethyl ethers (PODEn) and diesel as pilot fuels for natural gas DF combustion is presented. The experiments were conducted at two conditions: 1000 rpm 4 bar indicated mean effective pressure (IMEP), and 1000 rpm 12 bar IMEP. Compressed natural gas (CNG) was injected into the intake manifold and pilot fuel was injected directly into the cylinder. The experiments covered both conventional and low temperature DF combustion. Experiments were conducted with 0% exhaust gas recirculation (EGR) and 60% CNG substitution ratio at 4 bar IMEP. At 12 bar IMEP, 90% substitution ratio and 30% EGR rate were chosen. The impact of the start of pilot fuel injection (SOI) on natural gas DF combustion was studied. In comparison with the conventional combustion, low temperature combustion reduced NOx emissions and improved ITE. Compared to diesel, PODEn achieved lower THC, CO, NOx, soot emissions and higher efficiency, indicating it is a promising pilot fuel for natural gas DF combustion.