The unsteady flow of an incompressible fractional Maxwell fluid between two infinite coaxial cylinders is studied by means of integral transforms. The motion of the fluid is due to the inner cylinder that applies a ti...The unsteady flow of an incompressible fractional Maxwell fluid between two infinite coaxial cylinders is studied by means of integral transforms. The motion of the fluid is due to the inner cylinder that applies a time dependent tor- sional shear to the fluid. The exact solutions for velocity and shear stress are presented in series form in terms of some generalized functions. They can easily be particularized to give similar solutions for Maxwell and Newtonian fluids. Fi- nally, the influence of pertinent parameters on the fluid motion, as well as a comparison between models, is highlighted by graphical illustrations.展开更多
In this note the velocity field and the adequate shear stress corresponding to the unsteady flow of a frac- tional Maxwell fluid due to a constantly accelerating circular cylinder have been determined by means of the ...In this note the velocity field and the adequate shear stress corresponding to the unsteady flow of a frac- tional Maxwell fluid due to a constantly accelerating circular cylinder have been determined by means of the Laplace and finite Hankel transforms. The obtained solutions satisfy all imposed initial and boundary conditions. They can easily be reduced to give similar solutions for ordinary Maxwell and Newtonian fluids. Finally, the influence of pertinent param- eters on the fluid motion, as well as a comparison between models, is underlined by graphical illustrations.展开更多
Dissipation, power due to the shear stress at the wall and the boundary layer thickness corresponding to the unsteady flow of a second grade fluid, due to a constantly accelerating plate, are established in exact and ...Dissipation, power due to the shear stress at the wall and the boundary layer thickness corresponding to the unsteady flow of a second grade fluid, due to a constantly accelerating plate, are established in exact and approximate forms. The changing of the kinetic energy with time is also determined from the energetic balance. Exact expressions of the same entities for Newtonian fluids are recovered as limiting cases of general results.展开更多
文摘The unsteady flow of an incompressible fractional Maxwell fluid between two infinite coaxial cylinders is studied by means of integral transforms. The motion of the fluid is due to the inner cylinder that applies a time dependent tor- sional shear to the fluid. The exact solutions for velocity and shear stress are presented in series form in terms of some generalized functions. They can easily be particularized to give similar solutions for Maxwell and Newtonian fluids. Fi- nally, the influence of pertinent parameters on the fluid motion, as well as a comparison between models, is highlighted by graphical illustrations.
文摘In this note the velocity field and the adequate shear stress corresponding to the unsteady flow of a frac- tional Maxwell fluid due to a constantly accelerating circular cylinder have been determined by means of the Laplace and finite Hankel transforms. The obtained solutions satisfy all imposed initial and boundary conditions. They can easily be reduced to give similar solutions for ordinary Maxwell and Newtonian fluids. Finally, the influence of pertinent param- eters on the fluid motion, as well as a comparison between models, is underlined by graphical illustrations.
文摘Dissipation, power due to the shear stress at the wall and the boundary layer thickness corresponding to the unsteady flow of a second grade fluid, due to a constantly accelerating plate, are established in exact and approximate forms. The changing of the kinetic energy with time is also determined from the energetic balance. Exact expressions of the same entities for Newtonian fluids are recovered as limiting cases of general results.