Rheological Properties of KCL/Polymer Type Drilling Fluids Containing Particulate Loss Prevention Material

Abstract

Rheological properties of KCl/polymer type drilling fluids containing particulate loss prevention material (LPM) were characterized by an integrated inverse model-experimental approach. Rheological measurements for LPM-laden KCl/polymer type drilling fluids were carried out on a 6-speed rotational viscometer. The algorithm based on Tikhonov regularization was validated to be applicable and reliable to compute the shear rate in a rotational viscometer equipped with a widened annular gap. With the validated algorithm, the dial readings versus rotational speed data were transformed into shear stress vs. shear rate form. The results indicate that the rheological diagrams of the KCl/polymer type drilling fluids resemble those of a yield stress fluid and can be well represented by the Hershel-Bulkley model. The observed variation shows that rheological parameters were affected significantly by the addition of particulate LPM. The amount and the particle size of particulate LPM have a combined effect on the rheological properties of LPM-laden KCl/polymer type drilling fluids.

Keywords

• drilling fluid
• loss prevention material
• flow model
• tikhonov regularization