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Droplet breakup is a complex process involving interfacial instability and transport across a wide range of length and time scales. Fundamental studies of shock-droplet interaction provide valuable insight into the physical processes behind droplet breakup at high Weber and Reynolds numbers. Many high-speed applications such as liquid-fueled detonations and hypersonic hydrometeor impacts involve small droplets under high Weber numbers and/or unsteady conditions. The work presented here will explore deformation and hydrodynamics leading to breakup for small droplets (< 200μm) at high Weber numbers. An experimental campaign is presented whereby droplet deformation is measured at high temporal and spatial resolution. Small rapidly evaporating droplets (≈ 150μm) at Weber numbers in excess of 1000 are studied. High-speed (sub-microsecond image times) shadowgraphy provides measurement of the droplet deformation rate, acceleration, and breakup timing. DNS results are presented to further explore deformation rates for smaller droplets (≈ 5μm). Deformation rates are compared with existing models for both experimental and simulation cases. This ongoing work will provide additional data from which our understanding of complex droplet phenomena may be advanced and applied to physical systems.
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Investigation of Cavitation in Water Droplet Breakup from Shock Waves
The deformation and breakup of water droplets impacted by a shock wave has been largely attributed to surface mechanisms. This study investigates the possibility of cavitation-induced droplet breakup. Shock waves of Mach 4 are used in this study to impact groups of droplets, both groups of degassed droplets and a group of non-degassed droplets. Distilled water droplets on the order of 1-3 mm in diameter are introduced into the shock tube. High speed images and deformation plots are used to explore the existence of cavitation in the droplets, as well as how they deform comparatively.
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- Award ID(s):
- 2244324
- PAR ID:
- 10591084
- Publisher / Repository:
- American Institute of Aeronautics and Astronautics
- Date Published:
- ISBN:
- 978-1-62410-711-5
- Format(s):
- Medium: X
- Location:
- Orlando, FL
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.2514/6.2024-2191
