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In support of efforts to develop improved models of turbulent spray behavior and combustion in diesel engines, experimental data and analysis must be obtained for guidance and validation. For RANS-based CFD modeling approaches, representative ensemble average experimental results are important. For high-fidelity models such as LES-based CFD simulations, precise individual experimental results are desirable. However, making comparisons between a given experiment and LES simulation is a challenge since local parameters cannot be directly compared. In this work, an optically accessible constant pressure flow rig (CPFR) is utilized to acquire diesel-like fuel injection and reaction behavior simultaneously with three optical diagnostic techniques: rainbow schlieren deflectometry (RSD), OH* chemiluminescence (OH*), and two-color pyrometry (2CP). The CPFR allows a large number of repeated injection experiments to be performed for statistical analysis and convergence using ensemble-averaging techniques, while maintaining highly repeatable test conditions. Even for stable test conditions, variations in local turbulent fuel-air mixing introduce variability which manifests as significant differences in OH* and 2CP results. Experimental measurements of characteristic parameters including liquid and vapor jet penetration, lift-off length, soot temperature and concentration, and turbulent flame speed, along with the shot-to-shot variability of each data set, are presented and discussed. A statistical method is utilized to analyze the extent of this variability, and to identify superlative injections within the data set for discussion and analysis of shot-to-shot variations.

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