Study on Measurement Method of Micro Pulsating Flow Based on Graphene Film

The measurement of micro pulsating flow is crucial for monitoring of fluid variations, improving system efficiency, and optimizing production processes. This paper proposed a micro pulsating flow measurement method based on Fabry-Perot cavity using a CVD graphene film as the pressure sensitive material, providing ultrathin thickness, high elasticity, and exceptional pressure sensitivity. A complete theoretical model was derived, establishing a link between pulsating flow rate and optical power variation. A sensor prototype was fabricated and experimentally validated under a real flow experiment in millimeter-scale pipelines, achieving a sensitivity of 0.005 dBm/(mL/min) (theoretical: 0.004 dBm/(mL/min)) and the optimal combined relative standard uncertainty of 0.28% at a flow rate of 7.5 mL/min. This work demonstrates a novel, non-invasive, and highly precise approach for micro pulsating flow measurement in small-scale fluid systems, offering strong potential for applications in industrial production, biomedical engineering, and energy utilization.