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Title: Deformation of Small Droplets at High Weber Number
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.  more » « less
Award ID(s):
2053154
PAR ID:
10511678
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Institute for Liquid Atomization and Spray Systems 2024 Conference Proceedings
Date Published:
Journal Name:
Institute for Liquid Atomization and Spray Systems 2024 Conference Proceedings
Format(s):
Medium: X
Location:
Ithaca, Ny
Sponsoring Org:
National Science Foundation
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