Field measurements of soot volume fractions in laminar partially premixed coflow ethylene/air flames

Simultaneous soot temperature and volume fraction measurements in axis-symmetric flames by a two-dimensional modulated absorption/emission technique

“…While discrepancies with the numerical profiles by Blacha et al [24] appear, the peak soot volume fractions measured in the present study agree well with the ones measured by Arana et al [39], except at the highest HAB considered. At this height, the peak measured in the present study is shifted outward as compared to the one reported by Arana et al [39]. Yet, the profiles match one another in the vicinity of the flame's axis.…”

“…These authors reported some discrepancies between their numerical soot volume fraction and temperature fields and the measurements in the experimental study of McEnally et al [37]. Reproducing the experimental conditions of Santoro et al [38], Arana et al [39] also reported discrepancies among experimental measurements of soot volume fraction that can be especially attributed to the flow features in the vicinity of the burner tip. As a result, the quantitative agreement between the experimental and numerical maps shown in Fig.12 is not expected.…”

“…Consequently, the methodology developed within the framework of the present study to retrieve the fields of soot temperature and spectral absorption coefficient is believed to be adequate. Figure 13 shows the profiles of soot volume fraction at the three different heights above the burner where experimental data by Arana et al [39] are provided. These authors also implemented a Laser Extinction Method.…”

“…Arana et al [39] faced a similar issue and had to fit the soot refractive index to closely reproduce the profiles of Santoro et al [38]. As argued by Arana et al, the discrepancies among experimental data can be partly attributed to the high sensitivity of the onset of soot formation to the flow features in the vicinity of the burner tip.…”

Exploring Soot Particle Concentration and Emissivity by Transient Thermocouples Measurements in Laminar Partially Premixed Coflow Flames

“…The effect of partial premixing on soot formation has been previously investigated experimentally by laser induced incandescence [18] and light absorption [19]. The works done in ethylene flames have shown that, as consequence of oxygen addition, the soot volume fraction initially increases because of the enhancement of the local radical pool, and the modification in the hydrocarbon chemistry reaches a maximum and then decreases.…”