ChemKED for profile-resolved data: A discussion of some salient data standard features

Development of the open, human- A nd machine-readable ChemKED data standard for describing common observables used in fundamental combustion kinetics experiments has presently progressed to robustly describe ignition delay times and related supporting measurements (e.g., RCM volume histories). These single-valued "global" measurements offer some insight into combustion kinetics; however, additional understanding can be determined from interpretation of "profile" measurements typical of those from jet stirred reactors, flow reactors, species-resolving shock tubes, and burner-stabilized flames. Despite the utility of such measurements, the combustion community presently lacks a widely adopted data standard to facilitate archiving, sharing, and automated manipulation of profile data. Unlike global observables, profile measurements generally resolve the (co)evolution of one or more observables (e.g., species mole fractions and/or temperature) as a function of a continuous and independent spatial, temporal, or thermal coordinate intrinsic to a single chemical kinetics experiment. The numerous profile-resolving experiment types, their intrinsic experimental variables, and (multiple) observables each pose a potential challenge for transforming the existing global-type ChemKED data structure into one capable of handling profile-resolved data. Toward stimulating further discussion of a broadly acceptable data standard for profile measurements, the present work offers several concrete examples of these challenges and proposes an initial approach toward a generally satisfactory solution.