Development and validation of a quasi-dimensional combustion model for SI engines fuelled by HCNG with variable hydrogen fractions

• Published in: International journal of hydrogen energy Vol. 33; no. 18; pp. 4863 - 4875
• Main Authors: Ma, Fanhua, Wang, Yu, Wang, Mingyue, Liu, Haiquan, Wang, Junjun, Ding, Shangfen, Zhao, Shuli
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.09.2008; Elsevier
• Subjects: Applied sciences; Energy; Energy. Thermal use of fuels; Engines and turbines; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; HCNG engine; Laminar burning velocity; Numerical simulation; Quasi-dimensional model; Quasi-dimensional model; Laminar burning velocity; MFB; HCNG engine; Numerical simulation; NTP; MAP; NO x; CA; BTDC; Turbulent flame; Compressed gas; Hydrogen; Diesel engine; Combustion; Spark ignition engine; Flame propagation; Combustion velocity; Thermodynamic model; Gas engine; Natural gas
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2008.06.068

Spark ignition engines fuelled by hydrogen enriched compressed natural gas (HCNG) have many advantages compared to traditional gasoline, diesel and natural gas engines, especially in emission control. Experimental researches have been continuously conducted to improve HCNG engine's configuration and control strategy aimed at making full use of this new fuel. With the same target, this work presents a predictive model used to simulate the working cycle of HCNG engines which is applicable for variable hydrogen blending ratios. The fundamentals of the thermodynamic model, the turbulent flame propagation model and related equation were introduced. Considering that the most important factor influencing the applicability of the model for variable hydrogen blending ratio is the laminar flame speed, the methods of how to deal with the laminar burning velocity in the model were then described in some more detail. After the determination of model constants by calibration, simulation results were compared with experimental cylinder pressure data for various hydrogen blending ratios, spark timings and equivalence ratios. The results show that simulation and experimental results match quite well except for extremely fuel lean conditions where problems of incomplete combustion become severe.