Mathematical Modelling of Structures, Solids and Fluids
http://hdl.handle.net/2160/2918
2016-08-27T22:21:48ZA computational study of some rheological influences on the "splashing experiment"
http://hdl.handle.net/2160/43292
A computational study of some rheological influences on the "splashing experiment"
Tome, M. F.; McKee, S.; Walters, Ken
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.
2010-10-01T00:00:00ZSolution asymptotics near meximum friction surfaces in the plane strain b lock compression : various viscoplastic laws with saturation stress.
http://hdl.handle.net/2160/42024
Solution asymptotics near meximum friction surfaces in the plane strain b lock compression : various viscoplastic laws with saturation stress.
Mishuris, G.; Alexandrov, A.; Miszuris, W.
Jeulin, Dominique; Frost, Samuel
2008-01-01T00:00:00ZLocalisation and dynamic defects in lattice structures
http://hdl.handle.net/2160/42001
Localisation and dynamic defects in lattice structures
Mishuris, G.; Movchan, A.; Slepyan, L. I.
Silberschmidt, Vadim V.
This review paper outlines several formulations for lattice structures where dynamic lattice Green's functions play an important role in analysis of localization near defects as well as fracture in structured media. The mechanism of dissipation discussed here is natural for lattices modelling structured media. The properties of waves generated by cracks, and the exponentially localized vibration modes near small defects are linked to spectral properties of Bloch-Floquet waves in undamaged periodic media. The results outlined in this review paper are based on the work by (2002), (2007), (2007), (2008).
Mishuris, G., Movchan, A., Slepyan, L.I. (2009). Localisation and dynamic defects in lattice structures, In: Computational and Experimental Mechanics of Advanced Materials, CISM International Centre for Mechanical Sciences, P.D. Ruiz and V.V. Silberschmidt (Eds.), Springer, pp. 51-82
2009-01-01T00:00:00ZSolution asymptotics near maximum friction surfaces in plane strain block compression: various viscoplastic laws with a saturation stress
http://hdl.handle.net/2160/40104
Solution asymptotics near maximum friction surfaces in plane strain block compression: various viscoplastic laws with a saturation stress
Mishuris, Gennady; Miszuris, Wiktoria; Alexandrov, S.
The maximum friction requires that the friction stress is equal to the local shear yield stress of material. This law can be a source of singularities in rigid plastic solutions, including rigid viscoplastic solutions. For this reason, many classical solutions of rigid plasticity (rigid perfectly plastic solids) cannot be generalised when conventional rigid viscoplastic models are adopted. In the present paper, as class of rigid viscoplastic models with a saturation stress permitting for a generalisation of the famous Prandtl's solution for compression of a block between two parallel rough plates are considered and the corresponding generalisation of the solution is obtained.
Mishuris, G; Miszuris, W; Alexandrov, S. Solution asymptotics near maximum friction surfaces in plane strain block compression: various viscoplastic laws with a saturation stress. Eds: D. Jeulin, S. Forest. Proceedings of the International Symposium CMDS11. 2008, 225-230.
2008-01-01T00:00:00Z