Viscoelastic flow past a cylinder: drag coefficient Original Research Article

The channel flow of a viscoelastic fluid past a circular cylinder is simulated using a parallelized unstructured Finite Volume Method (FVM) [H.-S. Dou, N. Phan-Thien, J. Non-Newtonian Fluid Mech. 77 (1998) 21–51] under a distributed computing environment through the Parallel Virtual Machine (PVM) libraries. The numerical method is based on the SIMPLER (Semi-Implicit Method for Pressure-Linked Equations Revised) algorithm, using the simplified Phan-Thien/Tanner (PTT) and the Upper Convective Maxwell (UCM) constitutive models, with the Elastic Viscous Split Stress (EVSS) formulation. The parallelization of the program is implemented by a domain decomposition strategy and the PVM software. It is found that the both shear thinning and normal stress contribute to the drag reduction. With the PTT model, the drag reduction is mainly due to shear thinning. With the UCM model, it is primarily due to the normal stress effect.