Similitude-Based Technology to Study Wellbore Hydraulics

Abstract Accurate estimation of the wellbore equivalent circulation density (ECD) is crucial for effective well planning and drilling. This paper introduces a portable and compact hardware designed to study the two-phase annular hydraulics of arbitrarily inclined wellbores, providing detailed specifications and practical applications. The hardware design enables automated adjustments of the inner pipe eccentricity, rotation speed, total flowrate, and annular flow inclination. Measurements of solids and fluid flowrates along the hardware flow loop are separately conducted using a Coriolis meter. Control and data logging are facilitated through an integrated set of programmable controllers and data communication system with a built-in human-machine interface. The upscaling of measured pressure gradients along the flow loop annulus to those pressure gradients that would occur in a simulated wellbore annulus is achieved through a set of scaling equations. These scaling equations are developed using dimensional analysis and the simultaneous application of geometric, dynamic, and rheological similarities between the two scales of annular flow. A test case is presented to illustrate the workflow for estimating upscaled frictional pressure loss in a wellbore annulus.