Influence of Mixture Quality on Nonlinear Combustion Process of Natural Gas Engine

Combustion characteristic in a spark ignition natural gas engine was studied under different conditions of mixture quality based on chaos theory, in order to estimate nonlinear dynamic level in combustion system, we reconstructed attractor of combustion system using Indicated Mean Effective Pressure (IMEP), computed correlation dimensions and largest Lyapunov exponent (LLE) of the attractors, results show that there are low-dimensions chaos in combustion system of natural gas engine, particularly structure of the attractor become more and more complex and sensitivity of the system to initial conditions increases as increasing exhaust gas recirculation (EGR) rate.