TY - JOUR
T1 - A computational study of some rheological influences on the "splashing experiment"
AU - Tome, M. F.
AU - McKee, S.
AU - Walters, Ken
PY - 2010/10
Y1 - 2010/10
N2 - In various attempts to relate the behaviour of highly-elastic liquids in complex flows to their rheometrical behaviour, obvious candidates for study have been the variation of shear viscosity with shear rate, the two normal stress differences N(1) and N(2), especially N(1), the extensional viscosity, and the dynamic moduli G' and G ''. In this paper, we shall confine attention to 'constant-viscosity' Boger fluids, and, accordingly, we shall limit attention to N(1), eta(E), G' and G ''.We shall concentrate on the "splashing" problem (particularly that which arises when a liquid drop falls onto the free surface of the same liquid). Modern numerical techniques are employed to provide the theoretical predictions. We show that high eta(E) can certainly reduce the height of the so-called Worthington jet, thus confirming earlier suggestions, but other rheometrical influences (steady and transient) can also have a role to play and the overall picture may not be as clear as it was once envisaged. We argue that this is due in the main to the fact that splashing is a manifestly unsteady flow. To confirm this proposition, we obtain numerical simulations for the linear Jeffreys model. (C) 2010 Elsevier B.V. All rights reserved.
AB - In various attempts to relate the behaviour of highly-elastic liquids in complex flows to their rheometrical behaviour, obvious candidates for study have been the variation of shear viscosity with shear rate, the two normal stress differences N(1) and N(2), especially N(1), the extensional viscosity, and the dynamic moduli G' and G ''. In this paper, we shall confine attention to 'constant-viscosity' Boger fluids, and, accordingly, we shall limit attention to N(1), eta(E), G' and G ''.We shall concentrate on the "splashing" problem (particularly that which arises when a liquid drop falls onto the free surface of the same liquid). Modern numerical techniques are employed to provide the theoretical predictions. We show that high eta(E) can certainly reduce the height of the so-called Worthington jet, thus confirming earlier suggestions, but other rheometrical influences (steady and transient) can also have a role to play and the overall picture may not be as clear as it was once envisaged. We argue that this is due in the main to the fact that splashing is a manifestly unsteady flow. To confirm this proposition, we obtain numerical simulations for the linear Jeffreys model. (C) 2010 Elsevier B.V. All rights reserved.
KW - Boger fluids
KW - Splashing
KW - Rheometry
KW - Constitutive modeling
KW - Computational rheology
KW - FREE-SURFACE FLOWS
KW - OLDROYD-B MODEL
KW - COMPLEX FLOWS
KW - CONTRACTION
KW - DROP
UR - http://hdl.handle.net/2160/43292
U2 - 10.1016/j.jnnfm.2010.06.009
DO - 10.1016/j.jnnfm.2010.06.009
M3 - Article
SN - 0377-0257
VL - 165
SP - 1258
EP - 1264
JO - Journal of Non-Newtonian Fluid Mechanics
JF - Journal of Non-Newtonian Fluid Mechanics
IS - 19-20
ER -