Olivier Dubrunfaut

Application of microwave reflectometry to disordered petroleum multiphase flow study

Microwave reflectometry is applied to multiphase flow metering in the context of oil extraction. Our sensor consists of two open-ended coaxial probes operating at complementary frequencies (at 600 MHz and around 36 GHz) and was designed to resist harsh field conditions. This paper presents and comments on results obtained in realistic dynamic conditions, on a triphasic flow loop (water–oil–gas). The main conclusions are the following: Bruggeman–Hanais mixing rule applies to natural emulsions and can be used to determine the composition of the water–oil liquid phase; results obtained for annular flows are very sensitive to small perturbations such as bubbles or waves at the liquid–gas interface; in the case of triphasic slug flows, the composition of the liquid phase can be estimated by proper filtering of the data.

Direct and Inverse Modeling of a Microwave Sensor Determining the Proportion of Fluids in a Pipeline

A microwave sensor constituted of both low- and high-frequency probes is presented. The role of the sensor is to determine the proportion of mixed fluids in a pipeline used in petroleum engineering to extract oil from an oil layer. In this paper, the annular flow regime in the pipeline is considered. Since the analytical solution for this configuration is not available for high frequencies, a combination of numerical modeling and neural networks (NNs) is used. Two inversion configurations are compared. Good results are obtained with the better one.

Application of microwave reflectometry to biphasic flow characterization

In this paper, a modal resolution model of an open ended coaxial probe has been applied to the characterization of biphasic flows composed with water and gas. The sensitivity of the probe to the local fluid structure has been underlined. It has been shown that flow perturbations are responsible for the reduction of the range of applicability of the model.