Chaotic Analysis And Research Of Time Serious Of Pulse Combustion Flame Temperature

This paper from the view of nonlinear dynamics, by means of chaos theory and method to study the dynamic characteristics of the response of the flame to an acoustic excitation. The research object of this paper is laminar methane/air flame to the acoustic excitation. An experimental set up of Rijke-type pulse combustor has been build. Get the time series of flame temperature by two-thermocouple and dynamic temperature compensation. The main work and results are as follows:1.Built Rijke-type pulse combustion experimental platform, include Rijke heat and acoustic device, heat source control system, fuel control system and temperature measurement system, which can control and adjust pulse amplitude, fuel equivalence ratio and measure the flame temperature.2.Make error analysis of the thermocouple flame temperature measurement, and get the flame temperature by two-thermocouple. And make dynamic compensation for the flame temperature. The result shows that two-thermocouple measurement technology can promptly and accurately reflect the fluctuations and response of the flame temperature, which excited by acoustic. It can obtain the accurate time series of pulse flame temperature.3.Making the chaos test on pulse combustion time series of flame temperature by the largest Lyapunov exponent method, and using improved algorithm of the small amount of data method to c implement chaos detection. The result shows, the largest Lyapunov exponent are greater than zero on the pulsation combustion, which illustrate that time series of pulse combustion flame temperature is chaotic.4.Centering on the chaotic analysis of time series of pulsating flame temperature, this paper reconstructed the phase space with the temperature time series in different conditions, extracted chaotic features,such as correlation dimension and largest Lyapunov exponent. The chaos complexity of pulsating flame temperature and degree of chaos were estimated. The result shows that the chaos complexity of pulsating flame temperature and chaos intensity will increase with increase of the pulse amplitude. In addition, the degree of chaos of time series in flame front region is greater than other regions.