Steady Slow Flow of an Oldroyd 8-Constant Fluid in a Corner Region with a Moving Wall

Authors: SERDAR BARIŞ

Abstract: Viscoelastic fluids have gained increasing importance recently in technological applications. They are considered more realistic when compared to Newtonian fluids in some situations where flow phenomena can only be explained by using viscoelastic fluids' models. This paper discusses problem of dealing with the steady slow flow of an Oldroyd 8-constant viscoelastic fluid in a corner region with a moving wall. The aim of this study is to examine theoretically whether or not fluid elasticity is responsible for the formation of circulating cells near the corner, which has been observed experimentally in various polymer processes. Using series expansions given by Strauss (1975) for the stream function and stress components, the governing equations of the problem are reduced to linear ordinary differential equations. These equations have been solved analytically. It is shown that streamline patterns are strongly dependent on viscoelastic parameters. There is, unlike the case of Newtonian fluid, a secondary flow near the corner point.

Keywords: Non-radial flow, Oldroyd 8-constant fluid, Slow flow, Circulating cells.

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