Probing rate estimation methods for multiphase flow through surface chokes

Abstract

Choke is an essential device that controls flow rates at either subsurface or surface. Many models and correlations have appeared over decades handling multiphase flow through surface chokes. But, direct comparison of their relative performance has been a few, if any. This study evaluates several models and correlations to explore their relative performances. As expected, models anchored in thermodynamic principles outperformed others. Improvements in modeling followed the initial findings.We studied several models to explore their relative merits and ease of use in field settings. Seven different data sets gathered from laboratory and field settings, involving about 1000 independent data points, constituted the essence of this study. The study found the importance of PVT data in any flow through choke calculations. Specifically, we found that changes in density and heat capacity of fluids with pressure and temperature should be part of any rigorous effort for computation of flow rates.To ensure reliability and consistency in solutions, a model based on thermodynamic considerations deserve preference for generalized applications because it can handle pressure and temperature-dependent fluid properties. In this context, the recognition of choke-discharge coefficient's dependence on flow rate and Reynolds number constitutes an important element in ensuring the reliable outcome of results.