Piezoelectric Based Flow Power Harvesting for Downhole Environment

Abstract

Abstract There is a critical need for robust and reliable downhole power generation and storage technologies in order to push the boundaries of downhole sensing and control. Downhole power harvesting is an enabling technology for a wide range of future production systems and applications including self-powered downhole monitoring, downhole robotics, and wireless intelligent completions. This paper provides an analysis of available ambient energy sources in the downhole environment, and various energy harvesting techniques that can be employed to provide a reliable solution. Advantages and limitations of conventional technique like turbine are compared to advanced energy harvesting technologies. The power requirements and technical challenges related to different downhole applications have also been addressed. We have also presented a single-phase flow energy harvesting system based on vortex-induced vibrations by employing a bluff body in fluid flow. A laboratory experimental setup was developed that consists of a 2” flow loop, piezoelectric energy harvester, power management module, and capacitor storage. Computational fluid dynamics (CFD) simulations of the vortex-induced flow-vibrations for our setup have been presented. The generated vortex shedding frequencies and generated power in the flow loop is very low, which suggests requirement of a reliable rechargeable battery. Finally, recommendations are made for improvement and achieving the goal of practical implementation of downhole power harvesting.