Determining Rheological Parameters of Generalized Yield Power Law Fluid

Faculty of Drilling, Oil and Gas, AGH-UST

Poland, 30-058 Kraków, al. Mickiewicza 30,

Drilling muds used for oil drilling are described with various rheological models (Newtonian,

Bingham, Ostwald de Waele, Herschel-Bulkley). The Herschel-Bulkley model (Yield Power

Law) which best describes the rheological parameters of drilling fluids needs modifications.

Principles of determining rheological parameters of drilling mud described with a model of

Generalized Yield Power Law (GYPL) fluid were presented in the paper. The functions of shear

stresses and shear rate were given. Then the conditions of laboratory measurement of rheological

parameters of Generalized Yield Power Law fluids were introduced and the respective

mathematical dependences derived. On this basis, the rheological model parameters were

determined. When elaborating the block diagrams, the numerical methods for solving the

dependences were introduced. On this basis, rheological parameters of an exemplary drilling

mud were calculated.