Fibre optic flow sensing in deviated wellbores and pipelines

摘要

A wellbore 12 comprising a deviated section 18 is provided with at least one distributed fibre optic temperature sensor 38. The fibre optic temperature sensor 38 measures the temperature profile along at least two levels of a vertical axis 90 of the deviated section 18 using optical time domain reflectometry (OTDR). The temperature profiles at different positions along the vertical axis 90 are analysed to determine the cross-sectional distribution of fluids, the velocity and the flow rate of each fluid in the deviated section 18. Measurements may also be made to determine the flow rate of fluids in a subsea pipeline.