Analysis of slot flow approximations for annular flow of yield-power-law

It is the concern of both service companies and operators to understand the rheological behavior of drilling fluids under drilling conditions. In the past few year major advances have been done in the study of Yield Power Law fluids due to its capacity to study both power-law fluids at low shear and Bingham plastic fluids.
Understanding pressure drop-flow rate behavior in annulus is necessary to improve drilling operations. This thesis presents mathematical relationships between mud circulating rate and the respective pressure drop for Yield-power Law in a concentric annulus, with no drillpipe rotation. Based on this mathematical model pressure drop-flow rate relationships are obtained.
These results will help define the minimum pump power rate to be used during mud circulation into the well during drilling operations; it will also determine the pressure drop variation throughout the drillstring when circulating mud at a certain rate.