关键词: 物理化学 , 等离子体点火 , 非傅里叶传热 , 瞬态导热 , 数值模拟

Abstract: Instantaneous heat conduction analysis in powder grains was discussed. When the heat spread speed is a finite value in the process of plasma ignition, the theory of heat conduction is quite different from the classical Fourier law applied to the process when the heat spread speed is infinite. The classical Fourier law is modified when applied to the instantaneous heat conduction. A two-dimensional instantaneous heat conduction model of the powder grain plasma ignition process was established under cylindrical coordinate, using the finite difference equation and the numerical simulation to calculate the distribution of the temperature field in powder grains. In the process of the plasma ignition, different factors are considered to analyze the influences on the ignition delay, and the distribution of the temperature neld is also analyzed when a thermocouple is inserted in powder grains. The numerical results show that ： I) along with the increase of plasma temperature, tne ignition of energetic ma?terials is shortened; 2) the thickness of the plasma radiation absorption decreases, the ignition delay is small; 3) when the heat relaxation time decreases, the temperature field is further influenced; 4) when the thermocouple is inserted to measure the temperature, the temperature is influenced.

Key words: physical chemistry , plasma ignition , non-Fourier law heat transfer , instantaneous heat conduction , numerical simulation