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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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Arbitrary Lagrangian Eulerian Simulations of High Speed Particle Impacts Encountered During Hypersonic Flight
Particulate matter and small debris present in the atmosphere are known to cause substantial progressive damage to leading edges and control surfaces on hypersonic vehicles. This study seeks to predict the material responses (mechanical and thermal) to high-speed, small particle impact loading during hypersonic flight. To address such challenges, a multi-material fluid-based approach for modeling problems in this regime is examined. This method combines Arbitrary Lagrangian Eulerian (ALE) hydrodynamics with Adaptive Mesh Refinement (AMR) and multi- zone physics. The parameter regime of particles (2-5 μm) impacting a material surface at high speeds (125 - 600 ms−1) is investigated.
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- Award ID(s):
- 2005259
- PAR ID:
- 10420555
- Date Published:
- Journal Name:
- Proceedings of the International Conference on Computational Fluid Dynamics
- ISSN:
- 2330-6580
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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