Publications
Impact of Segregated Flow Modelling on Inflow Control Technologies for a Horizontal Well
Reservoir modeling can quantify the effect of using inflow control technology (ICT) to reduce the unwanted production of water and gas for horizontal wells.
Abstract
Due to the complexity of a reservoir the simulation software makes simplifications in terms of the physics in the reservoir to manage the simulation time. The effect of segregation in an open annulus is often excluded from simulation and it is assumed that all phases flow in a mix into the wellbore. This might affect the realism of the modeling seeing as the density segregation between oil, water, and gas could have a significant effect on the effectiveness of inflow control technology.
A well model has been set up to investigate the impact of segregated flow will have on two different inflow control technologies: a passive nozzle inflow control device (ICD) and an autonomous inflow control valve (AICV). The ICD is passive and will have the same flow area for all flowing conditions, while the AICV will autonomously adjust the flow area depending on the fluid. The two wells will first be simulated in a modeling software specifically designed to analyze the impact of segregation of fluids in the annulus using computational fluid dynamics (CFD), and the results from these simulations will be used to tune a near wellbore static simulator to quantify the impact segregation has on the production of the wells.
Adding additional complexity, such as segregation in annulus, to the reservoir modelling workflow creates a more realistic image of how fluids will behave in downhole conditions without complicating the reservoir model itself. By assuming annular segregation, parameters such as the number of swell packers, the length of compartments, the average deviation from horizontal wellbore, and the number of devices in a compartment will affect the oil production and water/gas choking of the wellbore. Due to the segregation more devices will be exposed to single phase flow, which causes the AICV to choke more water and gas compared to a situation without segregation.
Annular segregation is a well-documented phenomenon, as it is prevalent in both laboratory test data and from real production data from fields, but it is not always considered when modelling the expected production from oil wells. Including segregation modelling into the standard workflow for well modelling will increase the realism of the models, which decreases the discrepancy between modeled data and real production data.