Shear Rate Estimation: A Detailed Review

Abstract

The main objective of this paper is to review the work already done related to shear rate estimation for non-Newtonian fluids with or without yield point or yield stress with the help of basic integral equation of couette flow. Aqueous solution of drilling fluid additives is non-newtonian in nature and exact shear rate determination helps to predict rheological properties, i.e., apparent, plastic viscosity and yield point very accurately.This estimation helps to select appropriate drilling fluid for optimal penetration rate, which makes drilling economical by reducing rig days required to drill total depth. If the fluid additives are chosen correctly, we protect the well from sloughing shales, drill pipe sticking, fluid loss problem etc. and save time as well. Modern logging tools employ mud pulse telemetry to send data to surface which required suitable drilling fluid for proper data communication. It also affects productivity of well. Rising complexity of fluid has made it pertinent to improve acceptable estimation of shear rate determination of apparent viscosity, plastic viscosity and yield point. This paper examines the generalized difference equation for the coquette flow which is used in the evaluation of m (flow behavior parameter) and k (flow consistency parameter) for power law type fluid and Herschel-bulkley type fluid. The proposed shear rate equations which are considered are quite general and can be applied to any fluid.This review paper confines the equations which have been developed for the determination of shear rate along with the rheological properties for the non-Newtonian fluid with or without yield stress, which is essential for the prediction of suitable drilling fluid properties to achieve successful completion of an oil well.

Numerical and Experimental Analysis of Shear Stress Influence on Cellular Viability in Serpentine Vascular Channels

“…For the no-slip wall boundary condition with physiological flow at the inlet of serpentine (as given in Table 3 ), a small variation compared to the maximum magnitude of the shear rate was obtained near the wall due to rigidity of the wall of the serpentine channel as well as due to negligible variation of axial velocity magnitude [ 49 ]. There was minimum fluid velocity near the wall, which produces a non-significant variation of axial velocity near the wall.…”

Applicability of the Cox-Merz Rule to High-Density Polyethylene Materials with Various Molecular Masses

“…We calculated the wall shear stress according to [ 34 ] where is the radius of the capillary, the pressure drop, and the length of the die capillary. The apparent shear rate was calculated by [ 34 ] where is the volume flow through the capillary die. The Bagley correction [ 35 ] was used to correct for entry flow effects of the capillary.…”

“…We calculated the wall shear stress relative to the pressure drop and the apparent shear rate relative to the volume flow in a capillary slit of defined height , length , and width according to [ 34 ]: …”

“…A Rheograph 25 (Göttfert Werkstoff-Prüfmaschinen GmbH) high-pressure capillary rheometer with two different dies (diameter = 1 mm, length = 1 mm; diameter = 1 mm; length = 20 mm) was used to measure the polymer at a temperature of 200 • C. The shear viscosity was measured at shear rates between 1 and 5000 s −1 . We calculated the wall shear stress τ w according to [34]…”