Optical properties and pyrolysis of shock-heated gas-phase anisole
Optical properties and pyrolysis of shock-heated gas-phase anisole
复制标题
DOI：
10.1016/j.proci.2016.06.156
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
S. Zabeti;M. Aghsaee;M. Fikri;O. Welz;C. Schulz
中科院分区：
文献类型：
--
作者：
S. Zabeti;M. Aghsaee;M. Fikri;O. Welz;C. Schulz
苯甲醚（C6 H5 OCH 3）先前已被确定为基于激光诱导荧光（LIF）的燃料/空气混合研究的荧光示踪剂，其提供比常用甲苯更强的信号（Faust等人（2013））。苯甲醚LIF在高温下的可靠和定量应用需要了解其物理性质和热稳定性。在这项工作中，紫外线吸收和LIF的苯甲醚作为时间的函数，在565和1620 K之间的温度和压力为1.3和2.9巴的冲击加热的气体进行了测量。在240-310 nm光谱范围内以50 µs的时间分辨率获得吸收光谱。用266 nm激光激发，在不同的固定反应时间下，在反射激波后记录了苯甲醚的LIF发射光谱。测定了相对荧光量子产率，将先前报道的数据扩展到980 K以上。在T> 1000 K时苯甲醚开始热解后，报道了266 nm激发后的有效吸收截面和相应的LIF信号。为了帮助解释这些实验，苯甲醚热解的产品进行了研究，使用激波管耦合到一个高重复率的飞行时间质谱仪（HRR-TOF-MS）的时间分辨多物种测量。苯甲醚和产品，如苯，C2 H4，和CO的浓度-时间曲线进行了测量和比较，使用两个动力学模型从文献模拟。
Anisole (C6H5OCH3) has previously been identified as a fluorescence tracer for fuel/air mixing studies based on laser-induced fluorescence (LIF) that provides stronger signal than the frequently-used toluene (Faust et al. (2013)). Reliable and quantitative application of anisole LIF at high temperature requires knowledge about its photophysical properties and its thermal stability. In this work, ultraviolet absorption and LIF of anisole were measured as a function of time in shock-heated gases at temperatures between 565 and 1620 K and at pressures of 1.3 and 2.9 bar. Absorption spectra were acquired with 50 µs time resolution in the 240–310 nm spectral range. LIF emission spectra of anisole were recorded at different fixed reaction times behind reflected shock waves using 266-nm laser excitation. Relative fluorescence quantum yields were determined that extend previously reported data beyond 980 K. After the onset of pyrolysis of anisole atT> 1000 K, effective absorption cross-sections and the corresponding LIF signals after 266-nm excitation are reported. To aid the interpretation of these experiments, the products of anisole pyrolysis were investigated using a shock tube coupled to a high-repetition-rate time-of-flight mass spectrometer (HRR-TOF-MS) for time-resolved multispecies measurements. Concentration-time profiles for anisole and products such as benzene, C2H4, and CO were measured and compared to simulations using two kinetics models from literature.