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| Author(s): |
Laison Junio da Silva Furlan
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Presidente Prudente. 2018-09-12. |
| Institution: | Universidade Estadual Paulista (Unesp). Faculdade de Ciências e Tecnologia. Presidente Prudente |
| Defense date: | 2018-08-02 |
| Advisor: | Analice Costacurta Brandi |
| Abstract | |
The present work investigates the laminar-turbulent transition due to Tollmien-Schlichting waves for the incompressible two-dimensional Poiseuille flow of a viscoelastic fluid, using the Giesekus constitutive equation. Linear Stability Theory and Direct Numerical Simulation are used to verify the stability of viscoelastic fluid flows to unsteady disturbances. In the LST analysis, the Orr-Sommerfeld equation is modified to a viscoelastic fluid and solved by Shooting method. Whereas, in the DNS formulation, the Navier-Stokes equations with the Giesekus constitutive equation are solved using high-order compact finite difference methods. In order to evaluate the neutral stability curves and the amplification rates, different numerical simulations are performed by varying the dimensionless parameters in the Giesekus model and their results are compared with the Newtonian fluid. The LST and DNS techniques proved to be efficient tools to the spatial stability analysis of viscoelastic fluid flows of the Giesekus type, allowing a better comprehension of the dimensionless parameters influence of those flows, contributing with originals results to verification of the viscoelastics fluid flows stability using Giesekus fluid. (AU) | |
| FAPESP's process: | 17/11068-6 - Numerical simulation of viscoelastic fluid flows transition |
| Grantee: | Laison Junio da Silva Furlan |
| Support Opportunities: | Scholarships in Brazil - Master |