In this paper, the multi-step differential transform method (MDTM), one of the most effective method, is implemented to compute an approximate solution of the system of nonlinear differential equations governing the problem. It has been attempted to show the reliability and performance of the MDTM in comparison with the numerical method (fourth-order Runge–Kutta) and other analytical methods su...

INTRODUCTION This article investigates various improvements to two existing finite volume (fv) algorithms, specifically constructed to solve transient viscoelastic flow problems. Here, we consider model problems to identify fundamental algorithmic advances. Two alternative fv-approaches are advocated and contrasted for their properties, a hybrid cell-vertex scheme and a cell-centred staggered-g...

This work is devoted to the study of the stability of Hagen–Poiseuille flow or pipe flow. The analysis is focused on the streak breakdown process by which two-dimensional streamwise-independent finite amplitude perturbations transiently modulate the basic flow leading to a profile that contains saddle points and is linearly unstable with respect to very small streamwise-dependent perturbations....

Numerically computed spectra and pseudospectra are presented for the linear operator that governs the temporal evolution of infinitesimal perturbations of laminar flow in an infinite circular pipe at Reynolds numbers 1000, 3000 and 10 000. The spectra lie strictly inside the stable complex half-plane, but the pseudospectra protrude significantly into the unstable half-plane, reflecting the larg...

Soft bodies flowing in a channel often exhibit parachutelike shapes usually attributed to an increase of hydrodynamic constraint (viscous stress and/or confinement). We show that the presence of a fluid membrane leads to the reverse phenomenon and build a phase diagram of shapes-which are classified as bullet, croissant, and parachute-in channels of varying aspect ratio. Unexpectedly, shapes ar...

The linear stability problem for the Hocking–Stewartson pulse, obtained by linearizing the complex Ginzburg–Landau (cGL) equation, is formulated in terms of the Evans function, a complex analytic function whose zeros correspond to stability exponents. A numerical algorithm based on the compound matrix method is developed for computing the Evans function. Using values in the cGL equation associa...