Digital Solutions to Optimize Jet Pump Technology for Production Enhancement

Abstract

Artificial lift systems provide a reliable means for ensuring production through depleted wells. Traditional artificial lift technology is seriously challenged and has shown faster wear in tough operating environments at greater depths, high dog leg severities and multi-phase fluid environment. Jet pump technology with no moving parts and compact design is an excellent alternative for production enhancement in most challenging downhole conditions. In this paper digital computational fluid flow analysis is conducted to optimize the jet pump design to improve operational life of the jet pump and reduce non-productive time (NPT). Comprehensive laboratory testing is conducted and digital solutions are compared against the test data to validate the new jet pump technology. The operation of jet pump starts with flow of high pressure power fluid from surface into wellbore that travels through jet pump nozzle causing reduction in pressure which in turn draws in the reservoir fluid into jet pump throat. The low pressure generated at throat due to venturi effect can cause cavitation in certain scenarios and leads to reduced operational life of jet pump. To address this issue an alternative inverse jet pump is proposed that reverses the flow path of power fluid and production fluid. Numerical analysis is conducted to evaluate the feasibility of inverse jet pump design. Three-dimensional computational fluid dynamics (CFD) simulations are conducted using coupled algorithm with Reynolds-Averaged Navier-stokes (RANS) equation and k-ε turbulence model to predict the pressure and velocity flow field. Extensive laboratory testing is conducted in flow loop for the inverse jet pump design to validate the digital analysis results. CFD simulations are performed for different configurations of inverse jet pump by varying throat diameter and length of mixing chamber for operating production and power fluid flow rates. CFD results underscored the pressure and velocity profiles along the flow paths and based on digital analysis using CFD it is observed that innovative inverse jet pump design reduces probability of cavitation. Laboratory testing corroborated with digital analysis results and indicated improvement in operational life for inverse jet pump technology. Extensive usage of advanced computational modeling in this work assisted in optimizing design quickly and reduced time and cost associated with laboratory testing. This work elucidates use of digital solutions for design optimization of new production technology and underscores simulation-based-design as faster and cost effective method.