Phase volume fraction measurement of horizontal gas–liquid two-phase flow based on near-infrared absorption

Abstract In order to measure the phase volume fraction of shale gas–liquid two-phase flow, this paper designs a novel phase volume fraction measurement method based on near-infrared absorption. Firstly, we analyze the measurement mechanism of phase volume fraction based on the absorption characteristics of near-infrared spectroscopy, and determine the specific absorption wavelength for the gas and liquid phases. Then, we design a near-infrared sensor for the phase volume fraction measurement of gas–liquid two-phase flow, and optimize its structure by changing the parameters of the sensor lens through ZEMAX simulation to obtain the optimal near-infrared transmitting and receiving sensor. Finally, through establishing the simulation experiment platform of gas–liquid two-phase flow, we conduct the static and dynamic experiments under different working conditions, so as to establish the phase volume fraction calculation model. The results show that the optimized near-infrared sensor can be applied to the phase volume fraction measurement of gas–liquid two-phase flow. For static experiments, when the pressure is lower than 800 kpa, the measurement error of the wavelength of 980 nm near-infrared sensor is within ±4% for liquid volume fraction of 0%–100%. The measurement error of the wavelength of 1650 nm near-infrared sensor is within ±4% for liquid volume fraction of 0%–25%. For dynamic experiments, the measurement error of the developed sensor is within ±7% for liquid volume fraction.