Absorption and fluorescence of toluene vapor at elevated temperatures

Temperature measurements in a rapid compression machine using anisole planar laser-induced fluorescence

“…Similar approaches have been described in the literature. Strozzi et al [10] used PLIF to characterize a two-dimensional temperature field in an RCM, with a single-excitation, two-colour detection technique, relying on the temperature dependence of toluene fluorescence established by Koban et al [11], at atmospheric pressure and for the temperature range 300-950 K. These authors obtained temperature fields that clearly revealed a distorted structure, in particular at the boundary between the hot and cold zones. In-cylinder temperature imaging using a shock tube or spray has also been applied to the study of IC engines.…”

Toluene-based planar laser-induced fluorescence imaging of temperature in hypersonic flows

“…expected to be ∼ 2 × 10 −19 cm 2 within the 300-400 K range for 266-nm excitation as per Koban et al 2004;Cheung 2011), the region represented by each pixel in the PLIF image (x, y) can be effectively treated as an integration across each given spectral band and have its intensity correlated with temperature T. This relation permits application to constant pressure flows with homogeneous tracer distributions by means of a single-band approach, but the assumptions above do not apply to flows involving pressure changes and therefore with non-uniform tracer distributions. In such Schematic not to scale cases, a two-colour approach can be used, which relies in imaging the flow field using two different spectral filters, each of them imaging a different portion of the fluorescence spectrum.…”

“…An extensive characterisation of the photo-physical properties of toluene was carried out by Koban et al (2004), who documented a consistent red shift of the emission profile with increasing temperature, and with signal intensities of three orders of magnitude lower at 900 K in comparison with those at 300 K, for both 266-and 248-nm excitation. This study thus identified the potential high temperature sensitivities of toluene PLIF, which under certain conditions were found to be even up to two orders of magnitude higher than those obtained with more commonly used PLIF variances (e.g.…”

“…7, where the practically linear relation between temperature and PLIF ratio up to approximately 500 K can be observed for a number of filter combinations (e.g. Koban et al 2004;Miller et al 2013). For example, in the latter study by Miller et al (2013), the WG305 filter was chosen due to its wider spectral range (i.e.…”

“…Recent research has highlighted the potential of using toluene as a PLIF tracer for flow thermography applications given its strong temperature dependence (Koban et al 2004;Luong et al 2006;Yoo et al 2011;Miller et al 2013); however, one of the main related limitations is that the photo-physics of toluene fluorescence are only documented for a very narrow range of conditions. The present study aims at investigating the applicability of the toluene PLIF technique in hypersonic experimental research, for which temperature is a driving parameter, but yet the bulk of temperature measurements to date has been restricted to the surface of the model (Anderson 2000).…”