Rheological Properties of Drilling Fluids: Use of Dimensionless Shear Rates in Herschel-Bulkley and Power-law Models

An approach of Nelson and Ewoldt [1] to create a viscosity model of the Herschel-Bulkley type in order to use only parameters with the potential of containing fluid information has been extended to be applied to drilling fluids using current industry standard procedures. The commonly used Herschel-B...

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Bibliographic Details
Main Authors: Saasen Arild, Ytrehus Jan David
Format: Article
Language:English
Published: De Gruyter 2018-10-01
Series:Applied Rheology
Subjects:
Online Access:https://doi.org/10.3933/applrheol-28-54515
Description
Summary:An approach of Nelson and Ewoldt [1] to create a viscosity model of the Herschel-Bulkley type in order to use only parameters with the potential of containing fluid information has been extended to be applied to drilling fluids using current industry standard procedures. The commonly used Herschel-Bulkley consistency parameter k is found inadequate in describing fluid properties properly as it has a unit dependent on n. Hence, the model is not optimum for digitalisation. The Herschel-Bulkley model is re-written and base its parameters directly on the yield stress and the additional or surplus shear stress at a pre-determined shear rate relevant for the flow situation to be considered. This approach is also applicable for Power-Law models.
ISSN:1617-8106