Quenching measurements of Kr 5p[3/2] ← ← 4p S electronic transition using absorption spectra.

Quenching rate is an important parameter to include in fluorescence measurements that are aimed at quantifying the thermochemical field of a reacting flow. Traditionally, the quenching measurements were obtained at low pressures using the direct measurements of quenching times followed by a linear scaling to the desired pressure. This approach, however, cannot account for the possible deviation from the linear pressure scaling at elevated pressures due to three and multi-body collisions.

Mixture fraction measurement in turbulent non-premixed MILD jet flame using Rayleigh scattering.

Turbulent combustion of jet flames in a hot diluted coflow of combustion products is conducive to the transition from conventional flamelet combustion to a regime of moderate or intense low oxygen dilution (MILD) combustion, which is commonly characterized by a very low emission and noise. MILD combustion is also characterized by distributed combustion where the net heat release is positive across the entire combustion domain. The turbulence/chemistry interactions in this regime that determine the flame structure, local temperature, and species distribution critically depend on the mixture fraction and scalar dissipation fields.

Measuring the lengthening kinetics of aligned nanostructures by spatiotemporal correlation of height and orientation.

Owing to their inherent tortuosity, the collective height of vertically aligned nanostructures does not equal the average length of the individual constituent nanostructures, and therefore temporal height measurement is not an accurate measure of the genuine growth kinetics. We use high-resolution spatial mapping of alignment by small-angle X-ray scattering (SAXS) to transform real-time measurements of array height to the average length of the nanostructures. Applying this approach to carbon nanotube (CNT) forest growth transforms the kinetics from a sub-linear to a linear relationship with time, highlighting the potential for insights into the limiting growth mechanisms of CNTs and other one-dimensional nanostructures.