| 摘要 |
PROBLEM TO BE SOLVED: To measure the absolute light intensity of laser-induced incandescent light (LII) and to eliminate the need for calibrating known concentration and fine particles source by using the knowledge of the particle temperature from either the numerical model of the heating of fine particles or the empirical observation of the temperature of the fine particles. SOLUTION: A particle volume fraction is calculated by the knowledge of the particle temperature from either the numerical model of the heating of fine particles or the experimental observation of the temperature of the fine particles and by a known particle temperature. First, the response of a photodetector is calibrated. Then, a beam is applied to the volume of gas incorporating at least one particle by a pulse laser beam 2 and the incandescent light of at least one particle is generated by the pulse laser beam 2. Then, a prompt signal in the period of essentially invariable light intensity after a laser beam pulse is applied, a signal being integrated over a time period after the laser beam pulse is applied, and the signal of the incandescent light intensity of an incandescent light signal that is one of time-dependent signals are measured by a photodetector 4. Then, particle radiation is calculated by a computer 7, and the particle volume fraction is calculated from the signals of the intensity of incandescent light and that of absolute light.
|
