Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
NUMERICAL SIMULATION OF JET BUCKLING PHENOMENON OF VISCOELASTIC FLUID
Submission Author:
Reginaldo Merejolli , MS
Co-Authors:
Reginaldo Merejolli, Caroline Viezel, Laís Corrêa, Gilcilene Sanchez de Paulo
Presenter: Reginaldo Merejolli
doi://10.26678/ABCM.COBEM2023.COB2023-1246
Abstract
This work presents a numerical method for simulating three-dimensional viscoelastic free surface flows with focus on the jet buckling phenomenon using the Giesekus constitutive equation. Industrial applications of fluid flow with free surfaces are always present: applications including casting, container filling, extrusion and fluid jetting devices. The precise determination of the free surface is important especially if the flow is even determined by the position and curvature of the free surface. Therefore, there is an industrial interest in developing numerical tools that are capable of dealing with these free surface flow problems in both two and three-dimensions. However, this is not an easy task, since, in addition to solving the governing equations, it is necessary to determine the free surface of the fluid, which varies with time and space. Another challenge is to simulate flows subject to high Weissenberg numbers, since most numerical methods become unstable for Weissenberg > > 1. In order to overcome these challenges, the momentum equations are solved by a first order finite difference method on a staggered grid, while the Giesekus equations are tackled by a finite difference technique involving the conformation tensor, and the free surface is modelled by a front tracking technique based on the Marker-and-Cell method. The presented numerical method is verified by comparing the results obtained through mesh refinement for the flows in a tube and for a jet focusing on a flat plate (jet buckling). Convergence results were obtained by means of mesh refinement of the fully developed flow in a tube. Numerical results obtained from the simulation of the jet buckling include the measurements of the frequency of buckling for several values of the Weissenberg number. Additionally, the effect of the mobility parameter on the jet buckling phenomenon is investigated using high values of the Weissenberg number.
Keywords
Giesekus model, Jet buckling, Viscoelastic flow, Free surface, Finite difference Marker and Cell method
