Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: second grade fluids

Sortuj według:

Ogranicz wyniki do:

Rheology of polymer melts and solutions

Walicka A., Walicki E.

International Journal of Applied Mechanics and Engineering

2010

Vol. 15, no 4

1253-1271

In this work the authors consider some rheological models describing the fluid behaviours of polymer melts and solutions; these behaviours exhibit both viscoplastic and viscoelastic character. After presentation the bases of kinematics there were presented three dimensional models of pseudo-, visco-plastic and visco-elastic fluids of Rivlin-Ericksen and complex second grade fluids. Joining these models suitably one obtained the generalized models of second grade fluids. The connection between the above mentioned fluids is modelled in the following way: the constant coefficient of shear viscosity of a second grade fluid (Rivlin-Ericksen type) is replaced by a plastic viscosity taken from viscoplastic fluids. As an example the flow of generalized second grade fluid of the Shulman type in rectilinear channels is considered.

Flows of generalized second grade fluids in rectilinear channels

Walicki E., Walicka A.

Applied Mechanics and Engineering

1999

Vol. 4, no 2

375-395

In this work the authors consider laminar flows of generalized second grade fluids in rectilinear channels. These fluids do exhibit both viscoplastic and viscoelastic behaviour. In the model of fluid under analysis the viscoplastic behaviour is described by Shulman equation, and the viscoelastic behaviour by Rivlin-Ericksen equation for a second grade fluid. A connection between the above mentioned behaviours is modelled in the following way: the constant coefficent of shear viscosity of a fluid of second grade fluid is replaced by a shear viscosity taken from a viscoplastic fluid modelled by Shulman equation. If the normal stress coefficients are set equal to zero, this model reduces to the standard viscoplastic Shulman model. The solutions are obtained for Poiseuille and Couette flows in the case of constant values of material coefficients.