Engine Detonation Control And Research

The current society needs to face increasingly stringent energy crises and increasingly stringent emission regulations.The in-cylinder direct injection engine,can improve the fuel economy,power output and cold start emissions.Based on the platform of direct injection engine bench test,this paper designs a set of engine direct pressure injection cylinder internal pressure acquisition system and combustion analysis system,and analyzes the engine knock phenomenon for combustion and heat release rules,based on The law of combustion and heat release analyzes the knocking phenomenon of the engine and obtains an evaluation method for evaluating the degree of engine knock.In this paper,the combustion analysis of the engine is carried out by the self-developed direct injection engine cylinder internal pressure collection system.Among them,the research on the pressure curve of the direct injection engine cylinder shows that the maximum combustion pressure,the average direct injection engine cylinder pressure curve and the heat release rate curve.The combustion-related parameters such as the pressure rise curve,the combustion mass fraction curve,the combustion duration,the average effective pressure,and the cyclic variation are displayed and accessed.Moreover,this paper independently developed a knock analysis unit that appears in the engine operating condition.The knock is monitored and analyzed in real time.The in-cylinder pressure curve of a direct-injection engine with normal combustion under different working conditions and the in-cylinder pressure curve of a direct-injection engine at the time of knocking are collected on a direct-injection type engine,and then the spectrum and time-frequency diagram analysis of the heat release rate of the combustion are performed.It is found that in a certain frequency band,the in-cylinder energy of the engine when knocking is higher than that of the normal combustion;in the time-frequency diagram,it is found that the mixture generated at the end of the time-frequency diagram when the engine produces knocking is released during spontaneous combustion.A lot of energy.This majority of the energy is filtered and the heat release rate is integrated to account for the knock intensity in this band.And the maximum magnitude of the engine knock intensity of IHRR and most engineers was analyzed by linear regression analysis.After that,the paper found thatthere is a good correlation between the two.The correlation is above 90%.Thus,the IHRR can accurately describe the knock intensity of the engine and is much more accurate than the MAPO.Subsequently,the IHRR was subjected to the knock level threshold analysis on the direct-injection single-cylinder machine,and the linear correlation between the two heights was fully verified.The relevant research analysis of this paper laid a certain foundation for the accurate calibration of IHRR related parameters in the later research.