每年出版 6 期
ISSN 打印: 2150-766X
ISSN 在线: 2150-7678
Indexed in
NON-INTRUSIVE TEMPERATURE MEASUREMENT OF PROPELLANT FLAMES AND ROCKET EXHAUSTS ANALYZING BAND PROFILES OF DIATOMIC MOLECULES
摘要
Temperature is the dominating parameter of combustion processes. To achieve realistic results, non-intrusive methods must be applied in measuring flame temperatures. This can be realized by quantitative analysis of the emitted radiation. One well-known technique to determine intensity distribution is emission spectroscopy. Typically, the flame spectra in the ultraviolet (UV, < 350 nm) and visible (VIS, < 750 nm) are governed by band profiles of diatomic molecules. To obtain information about the temperature from their intensity distribution, the experimental values are compared to corresponding calculated spectra.
Therefore different transitions of the most important diatomic molecules occurring in flames, like OH, NH, CN, CH, C2, CuH, MgO and AlO, have been calculated and intensity distributions modeled. In most cases, the calculated spectra showed only a small deviation from the observed experimental intensity distributions. To determine the combustion temperatures of different processes, recorded experimental spectra were compared to calculated data by a least squares fit routine with the parameter temperature and halfwidth of the line profile. The method was applied to solid propellant flames and rocket exhausts. The temperatures determined showed realistic values compared to those obtained in other studies. The possibility of using different radicals in the same flame allows a clearer discussion of the values achieved.