A theoretical solution is presented for the forced convection heat transfer of a viscoelastic fluid obeying the Giesekus constitutive equation in a concentric annulus under steady state, laminar, and purely tangential flow. A relative rotational motion exists between the inner and the outer cylinders, which induces the flow. A constant temperature was set in both cylinders, in this study. The f...

too long. It generates a cascade of subtle errors that ultimately accumulate to a distorted picture of the man and his science and indeed early Victorian scientific communities. A varied and overwhelming array of evidence demonstrates that Darwin did not avoid publishing his theory for 20 years.” The only evidence that has ever been put forward for Darwin’s delay is circumstantial or ambiguous ...

In this study, we present experimental results on particle-wall collision in viscoelastic fluids. A sphere is released in a tank filled with poly(ethylene-oxide) (PEO) mixed with water with varying concentrations up to 1.5%. The effect of Stokes and Deborah numbers on the rebound velocity of a spherical particle colliding onto a wall is considered. It has been observed that the slope at which t...

With the increasing use of wormlike micelle solutions as rheological modifiers in many consumer products, the prediction of the behavior of these fluids has grown increasingly important in recent years. In this paper, the flow past a sphere falling at its terminal velocity through a column of a wormlike micelle solution is experimentally studied. The working fluid is an entangled wormlike micel...

In this work, the linear stability analysis of a pulsed Taylor-Couette flow is investigated in the case of a linear Maxwell fluid when both cylinders are subjected to an out-of phase modulation with equal modulation amplitude and equal modulation frequency. The linear problem is solved using the Floquet theory and a technique of converting a boundary value problem to an initial value problem. A...

-The instability of a viscoelastic fluid layer heated from below in a modulated gravitational field is studied numerically. Fluids satisfying the Maxwellian model and the Boussinesq approximation are considered. A system of linear equations with periodic coefficients describing the behavior of disturbances, is obtained by linear stability theory. The disturbances are expanded by double series o...