A Flexible Flow Velocity Sensor Based on Core‐Sheath Structured Triboelectric Nanogenerator for Underwater Environmental Monitoring

Abstract Traditional flow velocity sensors have limitations such as limited accuracy, environmental interference, and dependence on power supply. The high‐precision measurement and stable output of the flow velocity sensor are of great significance for the accuracy and reliability of marine environmental monitoring. The triboelectric nanogenerator (TENG), an emerging technology for energy harvesting and sensing, offers a promising solution for real‐time flow velocity monitoring. This paper presents a core‐sheath structured triboelectric nanogenerator (CS‐TENG) with an innovative design featuring flexible materials to enhance environmental adaptability. By leveraging the vortex‐induced vibration (VIV) effect, the device achieves efficient fluid kinetic energy harvesting through VIV‐induced mechanical vibration coupling, enabling omnidirectional flow velocity measurement. The experimental results show that the frequency of the output signal from CS‐TENG has a good linear relationship with the flow velocity, specifically, within a flow velocity range of 0.297–0.931 m s⁻¹, the correlation coefficient reached to 0.992. Wireless real‐time flow velocity monitoring is achieved by integrating the MCU with the LoRa. The results show that the CS‐TENG, as a high‐precision active sensor, provides an intelligent solution for marine environmental monitoring.