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NASA NTRS · 20230004061

High-Pressure, Normal-Gravity Droplet Combustion Experimental Hardware

Timothy S. Krause·Vittorio M. Valletta·Anthony L. Ogorzaly·Jay Owens·Daniel J. Gotti·Eric S. Neumann
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Abstract

The High-Pressure, Trans-Critical (HPTC) 1-g Liquid Droplet Combustion Experiments will assess the autoignition and combustion of liquid fuel droplets at elevated temperatures and pressures. These experiments are being conducted at the NASA Glenn Research Center in a manner similar to experiments performed in Glenn’s Zero Gravity Research Facility (ZGF) using the B drop vehicle. The modification to the test capabilities of the ZGF experiments in the new experimental configuration will allow researchers to continue performing normal-gravity liquid droplet combustion experiments without requiring the use of the ZGF test equipment. These normal-gravity experiments will be conducted at lower pressures than in the ZGF because the pressure vessel for this setup is limited to a maximum working pressure of 7.74 atm (99.1 psig) at 366.5 K (200 °F). This experimental configuration will enable development of a similar capability for conducting high-pressure combustion and supercritical oxidation research on the International Space Station. Experiments will be conducted with the capability of altering the ambient pressure, temperature, and gas concentrations, as well as the fuel type for each test. For these experiments, the test vessel operates at pressures up to 7.5 atm (95.5 psig), temperatures up to 1,073 K (1,472 °F) inside the insulated oven, and oxygen concentrations up to 30 percent.

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Timothy S. Krause, Vittorio M. Valletta, Anthony L. Ogorzaly, Jay Owens, Daniel J. Gotti, Eric S. Neumann. 2023-08-01. High-Pressure, Normal-Gravity Droplet Combustion Experimental Hardware. https://ntrs.nasa.gov/citations/20230004061

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Three Stage Cool Flame Droplet Burning Behavior of n-Alkane Droplets at Elevated Pressure Conditions: Hot, Warm and Cool Flame

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Droplet Combustion↗