本项目采用理论分析、数值模拟和实验研究等方法开展气体燃料缸内预混火焰稳定性的基础研究工作。通过建立气体燃料缸内预混湍流火焰分析模型，分析着火过程点火区域附近的湍流特征参数对初期火焰形成与发展的稳定性影响，研究火焰传播过程中缸内湍流的涡团结构分布对火焰面的作用，开展甲烷及掺混非烃气体成分的混合燃气在缸内预混燃烧的基础研究，通过实验分析获得不同初始条件下的火焰稳定性表征参量和火焰面结构，建立气体燃料预混火焰内在不稳定性分析模型，联合实验和数值计算揭示热膨胀、能量优先扩散、浮力等火焰内在不稳定影响因素以及湍流扰动对气体燃料着火初期火焰形态及结构的内在联系。在此基础上阐明氢组分对变组分气体燃料预混燃烧火焰稳定性的影响规律。本研究对深入认识内燃机缸内火焰燃烧特性和稳定性规律具有重要的学术意义。

The fundamental study on in-cylinder premixed flame stability of gas fuel will be conducted by using a combination of theoretical analysis, numerical simulation and experimental study. The in-cylinder turbulent premixed flame analysis model of gas fuel will be established so as to analyze the effect of turbulent characteristic parameters in the ignition area on flame stability of formation and evolution during ignition process and study how the distribution of turbulent eddy structure affects flame front during flame propagation. The fundamental study on in-cylinder premixed combustion of the methane and blends mixing with non-hydrocarbons is conducted, and the flame stucture and characteristic parameters of flame stability will be acquired through experimental analysis. The premixed falme intrinsic instability analysis model of gas fuel will be built. The dependency of fame shape and sturcture during initial ignition on intrinsically unstable factors such as thermal expansion, thermal-diffusive instability ,buoyancy et al. and turbulent disturbulence will be revealed by a combination of experiment and numericlal caculation. Thus the effect of hydrogen addition on gas fuel which can change its consitituents is clarified. The study is of great significance for in-depth understanding the in-cylinder combustion properties and rules of flame stability in internal combustion engine.