The aim is to resolve the difficulties of measurement of temperature at several thousands of Celsius degrees for some unstable non-equilibrium gas flows.Based on the molecular spectroscopy theory and inherent molecula...The aim is to resolve the difficulties of measurement of temperature at several thousands of Celsius degrees for some unstable non-equilibrium gas flows.Based on the molecular spectroscopy theory and inherent molecular structure characteristics of the CN radical,the dependence of the spectral profile on the rotational temperature(RT),vibrational temperature(VT)and optical apparatus function are numerically explored within some certain ranges.Meanwhile,by comparing the numerically calculated spectra with the experimental spectra of the CN radical,the corresponding RT and VT of the plasma induced by the interaction of the laser pulse from an oscillated Nd:YAG laser with the coal target are determined,respectively.In addition,a short discussion on the thermodynamic state and the energy transfer process of the CN radical is also given.展开更多
One-dimensional detonation waves are simulated with the three-step chain branching reaction model,and the instability criterion is studied.The ratio of the induction zone length and the reaction zone length may be use...One-dimensional detonation waves are simulated with the three-step chain branching reaction model,and the instability criterion is studied.The ratio of the induction zone length and the reaction zone length may be used to decide the instability,and the detonation becomes unstable with the high ratio.However,the ratio is not invariable with different heat release values.The critical ratio,corresponding to the transition from the stable detonation to the unstable detonation,has a negative correlation with the heat release.An empirical relation of the Chapman–Jouguet Mach number and the length ratio is proposed as the instability criterion.展开更多
文摘The aim is to resolve the difficulties of measurement of temperature at several thousands of Celsius degrees for some unstable non-equilibrium gas flows.Based on the molecular spectroscopy theory and inherent molecular structure characteristics of the CN radical,the dependence of the spectral profile on the rotational temperature(RT),vibrational temperature(VT)and optical apparatus function are numerically explored within some certain ranges.Meanwhile,by comparing the numerically calculated spectra with the experimental spectra of the CN radical,the corresponding RT and VT of the plasma induced by the interaction of the laser pulse from an oscillated Nd:YAG laser with the coal target are determined,respectively.In addition,a short discussion on the thermodynamic state and the energy transfer process of the CN radical is also given.
基金by the National Natural Science Foundation of China under Grant No 90916028.
文摘One-dimensional detonation waves are simulated with the three-step chain branching reaction model,and the instability criterion is studied.The ratio of the induction zone length and the reaction zone length may be used to decide the instability,and the detonation becomes unstable with the high ratio.However,the ratio is not invariable with different heat release values.The critical ratio,corresponding to the transition from the stable detonation to the unstable detonation,has a negative correlation with the heat release.An empirical relation of the Chapman–Jouguet Mach number and the length ratio is proposed as the instability criterion.
