Performance Analysis of a Fluidic Axial Oscillation Tool for Friction Reduction with the Absence of a Throttling Plate

Abstract

An axial oscillation tool is proved to be effective in solving problems associated with high friction and torque in the sliding drilling of a complex well. The fluidic axial oscillation tool, based on an output-fed bistable fluidic oscillator, is a type of axial oscillation tool which has become increasingly popular in recent years. The aim of this paper is to analyze the dynamic flow behavior of a fluidic axial oscillation tool with the absence of a throttling plate in order to evaluate its overall performance. In particular, the differences between the original design with a throttling plate and the current default design are profoundly analyzed, and an improvement is expected to be recorded for the latter. A commercial computational fluid dynamics code, Fluent, was used to predict the pressure drop and oscillation frequency of a fluidic axial oscillation tool. The results of the numerical simulations agree well with corresponding experimental results. A sufficient pressure pulse amplitude with a low pressure drop is desired in this study. Therefore, a relative pulse amplitude of pressure drop and displacement are introduced in our study. A comparison analysis between the two designs with and without a throttling plate indicates that when the supply flow rate is relatively low or higher than a certain value, the fluidic axial oscillation tool with a throttling plate exhibits a better performance; otherwise, the fluidic axial oscillation tool without a throttling plate seems to be a preferred alternative. In most of the operating circumstances in terms of the supply flow rate and pressure drop, the fluidic axial oscillation tool performs better than the original design.

Keywords

• axial oscillation tool
• output-fed bistable fluidic oscillator
• throttling plate
• computational fluid dynamics