TY - JOUR
T1 - Universal mechanism for air entrainment during liquid impact
AU - Hendrix, Maurice H.W.
AU - Bouwhuis, W.
AU - van der Meer, Roger M.
AU - Lohse, Detlef
AU - Snoeijer, Jacobus Hendrikus
PY - 2016
Y1 - 2016
N2 - When a millimetre-sized liquid drop approaches a deep liquid pool, both the interface of the drop and the pool deform before the drop touches the pool. The build-up of air pressure prior to coalescence is responsible for this deformation. Due to this deformation, air can be entrained at the bottom of the drop during the impact. We quantify the amount of entrained air numerically, using the boundary integral method for potential flow for the drop and the pool, coupled to viscous lubrication theory for the air film that has to be squeezed out during impact. We compare our results with various experimental data and find excellent agreement for the amount of air that is entrapped during impact onto a pool. Next, the impact of a rigid sphere onto a pool is numerically investigated and the air that is entrapped in this case also matches with available experimental data. In both cases of drop and sphere impact onto a pool the numerical air bubble volume Vb is found to be in agreement with the theoretical scaling Vb=Vdrop=sphere St
AB - When a millimetre-sized liquid drop approaches a deep liquid pool, both the interface of the drop and the pool deform before the drop touches the pool. The build-up of air pressure prior to coalescence is responsible for this deformation. Due to this deformation, air can be entrained at the bottom of the drop during the impact. We quantify the amount of entrained air numerically, using the boundary integral method for potential flow for the drop and the pool, coupled to viscous lubrication theory for the air film that has to be squeezed out during impact. We compare our results with various experimental data and find excellent agreement for the amount of air that is entrapped during impact onto a pool. Next, the impact of a rigid sphere onto a pool is numerically investigated and the air that is entrapped in this case also matches with available experimental data. In both cases of drop and sphere impact onto a pool the numerical air bubble volume Vb is found to be in agreement with the theoretical scaling Vb=Vdrop=sphere St
KW - IR-99586
KW - METIS-315169
U2 - 10.1017/jfm.2015.757
DO - 10.1017/jfm.2015.757
M3 - Article
VL - 789
SP - 708
EP - 725
JO - Journal of fluid mechanics
JF - Journal of fluid mechanics
SN - 0022-1120
ER -