Accurate, real-time water-cut measurements are critical in the oil industry for production monitoring and management. Traditional methods often require calibration specific to each well, which is time-consuming and inefficient. Our sensor addresses these challenges by providing a fast, non-intrusive, and calibration-free solution.

^{Optical schematic of the water sensor setup}

The sensor operates by probing water absorption lines near 5000 cm⁻¹ for low water cuts (0%–10%) and 7000 cm⁻¹ for high water cuts (10%–100%). It uses a gradient-based algorithm to distinguish between water and oil, without needing well-specific calibration. The system was validated using a benchtop flow-loop with oil substitutes (glycol, diesel, gasoline) and demonstrated high accuracy (±5% absolute, 95th percentile). It is immune to the presence of salt, sand, and temperature.

^{Overall algorithm used to retrieve water-cut from the measured spectra}

• Operational Efficiency: Enables real-time, in-situ monitoring of oil-water mixtures without calibration, improving productivity.
• Cost Reduction: Reduces the operational costs associated with traditional calibration processes and laboratory analyses.
• Field Applicability: Designed for harsh environments and resilient to common contaminants like salt and sand.