AN OBJECTIVE EXPLICIT FORMULATION BASED ON THE OLDROYD-B CONSTITUTIVE EQUATION

Authors

  • G. Mompean
  • R. L. Thompson
  • P. R. Souza Mendes

DOI:

https://doi.org/10.5380/reterm.v3i1.3487

Keywords:

non-Newtonian fluids, mathematical model

Abstract

In the present paper is shown how to obtain an objective explicit algebraic extra-stress model (AESM) based on differential constitutive equations for viscoelastic flows (Oldroyd B, White-Metzner, Phan-Thien-Tanner, etc). The formulation is developed for three-dimensional time-dependent flows. In a previous work, Mompean, 1998 obtained a non-objective algebraic model. This inconsistency is now removed introducing the relative-rate-ofrotation tensor making the model frame-invariant. A new generalized objective time derivative is also introduced, giving flexibility to the model. Calculations are performed with an Oldroyd B based AESM for a 4:1 contraction flow, showing good agreement with the original constitutive differential model. Several results with particular derivatives are obtained and an analysis guided by a flow type classifier is given. This formulation is able to include a prediction, not present in the Oldroyd B model, the viscometric second normal stress difference, N2.

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Published

2004-06-30

How to Cite

Mompean, G., Thompson, R. L., & Souza Mendes, P. R. (2004). AN OBJECTIVE EXPLICIT FORMULATION BASED ON THE OLDROYD-B CONSTITUTIVE EQUATION. Revista De Engenharia Térmica, 3(1), 36–44. https://doi.org/10.5380/reterm.v3i1.3487

Issue

Section

Ciência/Science