激波管中NTC 燃料预着火理论分析

In order to explain the fuel pre-ignition problem, this paper reviews the literature preignition experiment and theory, and compares the ignition experiment data of the typical NTC fuel DME in the shock tube under different equivalence ratios. Focusing on the analysis of the basic chemical characteristics of the fuel, the theoretical analysis of the pre-ignition process combined with the temperature perturbation sensitivity, heat dissipation characteristics and reaction time scale characteristics during the ignition delay time has clarified that the temperature perturbation sensitivity and the reaction time scale characteristics are the dominant factor of pre-ignition occurrence. This study found that DME and n-heptane are more prone to pre-ignition at lean equivalence ratio, low pressure, and low fuel concentration. The research in this paper provides a theoretical reference for judging and analyzing the occurrence conditions and mechanisms of other fuel pre-ignition phenomena.