Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
DNS OF NON-NEWTONIAN GIESEKUS FLUID FLOW STABILITY
Submission Author:
Analice Costacurta Brandi , SP , Brazil
Co-Authors:
Laison Junio da Silva Furlan, Marcio Teixeira de Mendonca, Arianne Silva, Matheus Tozo de Araujo, Leandro Franco de Souza, Analice Costacurta Brandi
Presenter: Analice Costacurta Brandi
doi://10.26678/ABCM.COBEM2017.COB17-0476
Abstract
Hydrodynamic instability has emerged as an active field of study in non-Newtonian fluid mechanics. The rising interest in this phenomenon originates mainly from its technological importance in the polymer industry. The flow of non-Newtonian fluids between parallel plates is a problem of considerable practical interest. In this paper, the stability of the non-stationary disturbances viscoelastic fluid is studied through the growth rate of Tollmien-Schlichting waves for incompressible Poiseuille flow. The mathematical model adopted for the non-Newtonian fluid stress tensor is the Giesekus. The analysis is carried out by means of Direct Numerical Simulation (DNS). In the DNS formulation, the Navier-Stokes equations along with the Giesekus constitutive equation are solved using high-order finite differences numerical model. Results are presented for the Oldroyd-B fluid and compared with the Giesekus fluid. The results show that the amplification rates obtained differ from the Newtonian fluid as the $\alpha$ values increase. Comparisons are presented considering the maximum amplification rates for Newtonian and non-Newtonian fluid for different values of the Reynolds number, Weissenberg number and mobility parameter.
Keywords
Laminar-turbulent transition, Giesekus fluid, Poiseuille flow, direct numerical simulation
