It has been well-known for over six decades that the addition of minute amounts of long polymer chains to organic solvents, or water, can lead to significant turbulent drag reduction. This discovery has had many practical applications such as in pipeline fluid transport, oil well operations, vehicle design and submersible vehicle projectiles, and more recently arteriosclerosis treatment. Howeve...

In this paper, a simplified spring-dashpot model is proposed to represent the complicated nonlinear response of some viscoelastic materials. Recently, the viscoelastic modeling has been adopted by many researchers to characterize some parts of the human body in bioengineering and to simulate many material properties in mechanical engineering, electronic engineering and construction engineering....

in the present work, the effect of fluid’s elasticity was investigated on the hydrodynamic instability of blasius flow. to determine the critical reynolds number as a function of the elasticity number, a two-dimensional linear temporal stability analysis was invoked. the viscoelastic fluid is assumed to obey the walters’ b fluid model for which base flow velocity profiles were fortunately avail...

Bulk rheological properties of viscoelastic fluids have been extensively studied in macroscopic shearing geometries. However, little is known when an active microscopic probe is used to locally perturb them far from the linear-response regime. Using a colloidal particle dragged periodically by scanning optical tweezers through a viscoelastic fluid, we investigate both, its linear and nonlinear ...

In the present work, the effect of fluid’s elasticity was investigated on the hydrodynamic instability of Blasius flow. To determine the critical Reynolds number as a function of the elasticity number, a two-dimensional linear temporal stability analysis was invoked. The viscoelastic fluid is assumed to obey the Walters’ B fluid model for which base flow velocity profiles were fortunately avail...

Transverse ridges are regions of anomalously high uplift that, run parallel to many of the transform fattits at mid-ocean ridges. Previous models of the formation of these ridges generally fail to explain the magnitude of uphft (between 1 and 8 km) or account for geophysical observations (which indicate that the ridges are dynamically uphfted by neutral or heavy, but not buoyant, material). How...

Plane Couette flow of viscoelastic fluids is shown to exhibit a purely elastic subcritical instability at a very small-Reynolds number in spite of being linearly stable. The mechanism of this instability is proposed and the nonlinear stability analysis of plane Couette flow of the Upper-Convected Maxwell fluid is presented. Above a critical Weissenberg number, a small finite-size perturbation i...