Converging Flow of Non-Newtonian Fluids Through an Abrupt Contraction

In this paper, the converging flow of non-Newtonian fluids through an abrupt contraction duct is discussed. In consideration of the stick-slip behaviour of viscoelastic liquids in this flow, an extended equation of converging flow boundary streamline is derived, using the minimal energy theory: r=R{{2(3n-1)3(n+1)[1-(R/Rp)3(n+1)/2]+(3n-1)3(n-1)Ke[(Rp/R)3(n−1)/2−1]}×(z/eR)+1}2/(3a-1) where R and Rp are the radius of the die and the reservoir respectively, n is the flow behaviour index and e the Bagley correction factor, z is the coordinate length variation, Le is the entry length of the die and r the radius of converging streamline at z.