Model development for flash boiling spray and validations with isooctane, hexane, ethanol and their binary mixtures

Journal Article · 01 August 2022 · Fuel

DOI: https://doi.org/10.1016/j.fuel.2022.123917 · OSTI ID:1977138

Gao, Suya ^[1]; Yan, Junhao ^[2]; Lee, Timothy H. ^[3]; Lee, Chia-Fon ^[2]

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1. University of Illinois at Urbana-Champaign, IL (United States); OSTI
2. University of Illinois at Urbana-Champaign, IL (United States)
3. Zhejiang University (China)

The objective of this study is to develop a comprehensive model for spray atomization under the consideration of flash boiling, which includes nucleation, bubble growth, and droplet breakup. Although flash boiling has been previously studied, there is still no well-established analytical and numerical model of their mechanisms, or general guidelines on the implementation of this atomization strategy. In this study, detailed formulations are elaborated for the unified spray atomization model under both non-flash and flash boiling conditions. Next, the model was implemented into CFD software and 3-D simulations were performed for model validations. Two fuel blends are tested: ethanol-isooctane blends and hexane-isooctane blends. Simulation results were compared with the experimental measurements conducted using two methodologies, DBI (Diffuse Backlight Imaging) system for spray images captured by a high-speed camera, and a PDA (Phase Doppler Anemometry) system for droplet size measurement during the spray injection process. It was found that the current flash boiling model can accurately capture the spray characteristics under different environment conditions, such as the spray plume interactions and liquid penetration. The averaged Sauter mean diameter (SMD) calculations match the measurement sufficiently well. The spray structures for both single- and multi-component fuels during the injection process are well represented by current model.

• Research Organization: University of Illinois at Urbana-Champaign, IL (United States)
• Sponsoring Organization: Tank and Automotive Research, Development, and Engineering Center (TARDEC),; USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• Grant/Contract Number: EE0007309
• OSTI ID: 1977138
• Journal Information: Fuel, Journal Name: Fuel Journal Issue: C Vol. 321; ISSN 0016-2361
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English