Abstract
Understanding the fundamental physical process involved in drop impacts is important for a variety of engineering and scientific applications. Despite exhaustive research efforts on the dynamics of drop morphology upon impact, very few studies investigate the fluid dynamics induced within a drop upon impact. This study employs planar particle image velocimetry (PIV) with fluorescent particles to quantify the internal flow field of a drop impact on a solid surface. The image distortion caused by the curved liquid–air interface at the drop boundary is corrected using a ray-tracing algorithm. PIV analysis using the corrected images has yielded interesting insights into the flow initiated within a drop upon impact. Depending on the pre-impact conditions, characterized by impact number, different vortex modes are observed in the recoil phase of the drop impact. Further, the strength of these vortices and the kinetic energy of the internal flow field have been quantified. Our studies show a consistent negative power law correlation between vortex strength, internal kinetic energy and the impact number.
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References
Agbaglah G, Thoraval MJ, Thoroddsen ST, Zhang LV, Fezzaa K, Deegan RD (2015) Drop impact into a deep pool: Vortex shedding and jet formation. J Fluid Mech 764:1. doi:10.1017/jfm.2014.723
Attinger D, Moore C, Donaldson A, Jafari A, Stone HA (2013) Fluid dynamics topics in bloodstain pattern analysis: Comparative review and research opportunities. Forens Sci Int 231.1:375–396
Bernardin JD, Clinton JS, Mudawar I (1996) Effects of surface roughness on water droplet impact history and heat transfer regimes. Int J Heat Mass Transfer 40.1:73–88
Chandra S, Avedisian CT (1991) On the collision of a droplet with a solid surface. Proc R Soc Lond A Mat 432.1884:13–41
Clanet C, Béguin C, Richard D, Quéré D (2004) Maximal deformation of an impacting drop. J Fluid Mech 517.1:199–208
Glycerine Producers (1963) Association physical properties of glycerine and its solutions. Glycerine Producers’ Association, New York
Howland J.C, Antkowiak A, Castrejon-Pita R, Howison S.D, Oliver J.M, Style R.W, Castrejon-Pita A.A (2016) Its harder to splash on soft solids. PRL 117:184502–1:5
Hulse S, Lee, Illes M (2007) A blind trial evaluation of a crime scene methodology for deducing impact velocity and droplet size from circular bloodstains. J Forens Sci 52.1:65–69
Lee JS, Weon BM, Je JH, Fezzaa K (2012) How does an air film evolve into a bubble during drop impact? Phys Rev Lett 109.20:204501
Li EQ, Thoroddsen ST (2015) Time-resolved imaging of a compressible air disc under a drop impacting on a solid surface. J Fluid Mech 780.1:636–648
Minor G, Oshkai P, Djilali N (2007) Optical distortion correction for liquid droplet visualization using the ray tracing method: further considerations. Meas Sci Tech 18.11:23–28
Mohamed-Kassim Z, Longmire EK (2003) Drop impact on a liquid–liquid interface. Phys Fluids 15.11:3263–3273
Ninomiya N, Yasuda K (2006) Visualization and PIV measurement of the flow around and inside of a falling droplet. J Vis 9.3:257–264
Pruppacher HR, Beard KV (1971) A wind tunnel investigation of the internal circulation and shape of water drops falling at terminal velocity in air. Q J R Meteorol Soc 97.411:133–134
Rieber M, Frohn A (1999) A numerical study on the mechanism of splashing. Int J Heat Fluid Flow 20.5:455–461
Rioboo R, Tropea C, Marengo M (2001) Outcomes from a drop impact on solid surfaces. At Sprays 112:155–165
San Lee J, Park SJ, Lee JH, Weon BM, Fezzaa K, Je JH (2015) Origin and dynamics of vortex rings in drop splashing. Nat Commun 6.doi:10.1038/ncomms9187
Sharma PP, Gupta SC, Foster GR (1995) Raindrop-induced soil detachment and sediment transport from interrill areas. Soil Sci Soc Am J 59.3:727–734
Thoraval MJ, Takehara K, Etoh TG, Popinet S, Ray P, Josserand C, Thoroddsen ST (2012) von Kármán vortex street within an impacting drop. Phys Rev Lett 108 0.26:264506
Thoraval MJ, Takehara K, Etoh TG, Thoroddsen ST (2013) Drop impact entrapment of bubble rings. J Fluid Mech 724.1 :234–258
Thoroddsen ST, Etoh TG, Takehara K (2003) Air Entrapment under an impacting drop. J Fluid Mech 478.1:125–134
Weiss DA, Yarin AL (1999) Single drop impact onto liquid films: Neck distortion, jetting, tiny bubble entrainment, and crown formation. J Fluid Mech 385.1 :229–254
Xu L, Zhang WW, Nagel SR (2005) Drop splashing on a dry smooth surface. Phys Rev Lett 94.18:184505
Yarin AL (2006) Drop impact dynamics: splashing, spreading, receding, bouncing and hellip. Annu Rev Fluid Mech 38.1:159–192
Yarin AL, Weiss DA (1995) Impact of drops on solid surfaces: self-similar capillary waves, and splashing as a new type of kinematic discontinuity. J Fluid Mech 283.1:141–173
Zhang LV, Toole J, Fezzaa K, Deegan RD (2012) Evolution of the ejecta sheet from the impact of a drop with a deep pool. J Fluid Mech 690.1 :5–15
Zhao R, Zhang Q, Tjugito H, Cheng X (2015) Granular impact cratering by liquid drops: understanding raindrop imprints through an analogy to asteroid strikes. Proc Natl Acad Sci 112(2):342–347
Acknowledgements
This work is supported by Office of Naval Research–United States under Grant # N000140910141 (Program manager: Dr. Ronald Joslin) and Grant # 12044075 (Program manager: Dr. Thomas Fu), and the startup of Jiarong Hong from the University of Minnesota.
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Kumar, S.S., Karn, A., Arndt, R.E.A. et al. Internal flow measurements of drop impacting a solid surface. Exp Fluids 58, 12 (2017). https://doi.org/10.1007/s00348-016-2293-7
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DOI: https://doi.org/10.1007/s00348-016-2293-7