Towards laser-induced fluorescence of nitric oxide in detonation

This study aims to validate the new developments in our in-house spectroscopic code (KAT-LIF) to perform NO-LIF simulations for detonation conditions, as well as evaluating the capabilities of the NO-LIF diagnostic for characterizing H\(_2\)-air detonations. This objective was achieved in several steps. First, our in-house spectroscopic tool, KAT-LIF, was updated to perform NO-LIF simulations by notably developing a database of NO(A-X) transitions, currently unavailable in conventional spectroscopic databases, as well as collecting and implementing species-specific line broadening, line shifting, and quenching parameters for NO-LIF. Second, the validation of KAT-LIF was performed by comparing the simulation results with pre-existing simulation tools (LIFSim and LIFBASE) and experimental NO-LIF measurements in a laminar CH\(_4\)-air flame and H\(_2\)-air detonation. The validation results present satisfactory agreement of KAT-LIF and other simulation tools (LIFBASE, LIFSim) with experimental results for several conditions. For example, less than 20% discrepancy between the simulated and experimental NO-LIF profiles is observed for stoichiometric H\(_2\)-air detonation, initially at 20 kPa and 293 K. Third, qualitative and quantitative capabilities of the NO-LIF technique for detonation characterization are discussed, which include: shock detection, induction zone length measurements, and quantitative number density measurements.