NON-NEWTONIAN FLUID FLOW IN AN ECCENTRIC ANNULUS

Abstract

Non-Newtonian fluid flow in an eccentric annulus was studied for high polymer aqueous solutions of CMC, HEC and MC. The macroscopic relations between the pressure drop and the flow rate were found to be in fairly good agreement with the results obtained by application of the conventional variational principle. Velocity profiles were measured by a hydrogen bubble method in which photographs were taken of the hydrogen bubbles. The authors observed very interesting secondary flows in the eccentric non-Newtonian fluid flow which may be due to the viscoelastic effect of the high polymer aqueous solution. The authors could not observe such secondary flows for non-Newtonian fluids in a concentric annulus or Newtonian fluids in an eccentric annulus. The authors present an equation giving the relation between the flow rate and the pressure drop for the flow of a non-Newtonian fluid in an eccentric annulus in terms of the experimental data for flow in a circular tube.