Advanced multitude of experiments ranging from the liquid fuel to combustion are conducted on Co-OPTIMA fuels to aid the characterization of the fuels. The series of targeted experiments characterized Co-OPTIMA fuel spray atomization, flame topology, flame speed, autoignition, volatility, viscosity, soot/coking, and compatibility. The fuels are selected and prioritized based on input from national lab members. The research characterized and predicted biomass-based, low greenhouse gas fuels and blends combustion, autoignition, and physical properties of mixtures of identified compounds at engine-relevant conditions, in particular those properties that blend non-linearly. The main challenge of Co-OPTIMA is the evaluation of a variety of biofuels and blends in all the reaction conditions that might be encountered in new high-efficiency engines. Despite the improved high-throughput experimental techniques, it seems unlikely that all of the performance metrics could be measured for all relevant petroleum derived, bio-derived molecules and mixtures, and reaction conditions. A series of targeted experiments ranging from the liquid fuel to the combustion process is required, and to extract the maximum information from each experiment. These targeted experiments evaluated how a specific fuel will perform in an engine. The series of targeted experiments are as follows: <
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(a) Spray Atomization, Vaporization and Droplet Formation <
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(b) Combustion Flame and Local Fuel/Air Image-Based Measurements <
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(c) Laminar Flame Speed Measurements <
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(d) Autoignition and Soot Measurements <
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(e) Synchrotron Coupled Fundamental Autoignition Experiments <
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(f) Fuel Coking and Hot Surface Deposit <
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g) Fuel Volatility Measurements <
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(h) Viscosity Measurements <
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(i) Seal Flexible Fuel Compatibility <
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These experimental processes provide an essential pathway for the prediction of fuel behaviors in engines and systematic process for fuel down select.