@article{santoianni_decroix_roberts_2001, title={Temperature imaging in an unsteady propane-air counterflow diffusion flame subjected to low frequency oscillations}, volume={66}, ISSN={["1573-1987"]}, DOI={10.1023/A:1011465203719}, number={1}, journal={FLOW TURBULENCE AND COMBUSTION}, author={Santoianni, DA and DeCroix, ME and Roberts, WL}, year={2001}, pages={23–36} }
 @article{welle_roberts_decroix_carter_donbar_2000, title={Simultaneous particle-imaging velocimetry and OH planar laser-induced fluorescence measurements in an unsteady counterflow propane/air diffusion flame}, volume={28}, ISSN={["1873-2704"]}, DOI={10.1016/s0082-0784(00)80609-8}, abstractNote={To study the transient response of a diffusion flame to an unsteady flowfied, quatitative measurements of velocity, using particle-imaging velocimetry, and OH measurements, using planar laser-induced fluorescence, were made simultaneously in an oscillating conterflow diffusion flame. These non-intrusive measurements were performed to spatially and tempoerally resolved flowrield and flame characteristics as a function of initial strain rate and forcing frequency. For the forcing frequencies considered in this study, the strain rate fluctuations were found to lag the velocity fluctuations, but the phase difference decresed with increasing forcing frequency. At lower forcing frequencies, the width of the OH field responded quasi-steadily, but as the forcing frequency increased, the OH field showed transient effects. The dilatation velocity, defined as the difference between the minimum velocity in the preheat zone and the maximum velocity in the reaction zone, was used as a flame temperature indicator. The dilatation velocity revealed that the phase difference between the velocity and the temperature increased with increasing forcing frequency, confirming the existence of a diffusion limited response. The resuls presented here help to illuminate the interconnecting relationships between the chemistry, fluid dynamics, and reactant transport times.}, journal={PROCEEDINGS OF THE COMBUSTION INSTITUTE}, author={Welle, EJ and Roberts, WL and Decroix, ME and Carter, CD and Donbar, JM}, year={2000}, pages={2021–2027} }
 @article{decroix_roberts_2000, title={Transient flow field effects on soot volume fraction in diffusion flames}, volume={160}, ISSN={["0010-2202"]}, DOI={10.1080/00102200008935801}, abstractNote={Quantitative measurements of soot concentration made in an oscillating propane-air counterflow diffusion flame are presented. The non-intrusive laser induced incandescence (LII) technique was used to make spatially and temporally resolved measurements of soot volume fraction in these transient flames as a function of initial steady strain rate, forcing frequency, and forcing amplitude of the strain rate fluctuation. The results of this study show that the soot formation process becomes insensitive to fluctuations in strain rate at high initial strain rates. At low initial strain rates, however, the maximum soot concentration is drastically reduced with high frequency, high amplitude fluctuations compared to the corresponding steady strain soot volume fraction. Low frequency oscillations are found to always increase the maximum soot concentration, by up to a factor of six for some conditions. These measurements provide important insight into the response of the chemistry control1ing the soot formation process in flamelets subject to unsteady rates of strain.}, journal={COMBUSTION SCIENCE AND TECHNOLOGY}, author={Decroix, ME and Roberts, WL}, year={2000}, pages={165–189} }
 @article{decroix_roberts_1999, title={Study of transient effects on the extinction limits of an unsteady counterflow diffusion flame}, volume={146}, ISSN={["0010-2202"]}, DOI={10.1080/00102209908924208}, abstractNote={Extinction strain rates in unsteady methane- and propane-air counterflow diffusion flames were experimentally measured as a function of initial strain rate, oscillation frequency, and amplitude of the imposed fluctuation. The maximum strain rate was found to occur at a temporal phase corresponding to the maximum velocity for the diluted methane flame. However, for the propane flame the maximum strain rate occurred when the imposed velocity fluctuation was zero and decreasing. Above an oscillation frequency of 100 Hz, the diluted methane flame was able to survive peak strain rates exceeding the steady extinction strain rate. The minimum air velocity in the pure methane and propane flames was negative for all cases studied, which is most likely responsible for flame extinction at low frequencies and initial strain rates. However, at high initial strain rates and forcing frequencies peak unsteady strain rates at extinction approached the steady extinction strain rate and flow reversal was much less significant.}, number={1-6}, journal={COMBUSTION SCIENCE AND TECHNOLOGY}, author={Decroix, ME and Roberts, WL}, year={1999}, pages={57–84} }