An arbitrary Lagrangian-Eulerian approach for simulating stratified viscoelastic fluids

A numerical technique based on the simplified arbitrary Lagrangian-Eulerian (simplified ALE) method for simulating the behavior of time-dependent inte rfacial stratified fluids is described. From the calculation of an integral -type constitutive equation, the strain history is obtained by the memory i ntegration method in a moving Lagrangian grid. Excess distortion of mesh el ements due to fluid straining is overcome by the use of an arbitrary Lagran gian-Eulerian treatment of the continuous mesh re-zoning. The scheme is app lied to simulate an interfacial deformation of stratified fluids at the Y-j unction of two laminar layers. From results of a benchmark calculation, the present scheme is found to show good agreement with previous numerical wor ks of pure viscous and shear-thinning fluids. Moreover, the present results predict some important flow phenomena that can appear in the flow geometry of viscoelastic fluids. (C) 2000 Elsevier Science B.V. All rights reserved .