Li Hongwei, Zhang Jinling, Yan Zhijun, Lyu Guohui
Opt Express. 2021 Nov 22;29(24):40015-40023. doi: 10.1364/OE.441255.
We propose and experimentally demonstrate an airflow velocity sensing method based on a 45° tilt fiber grating (TFG) that is combined with a single-walled carbon nanotube (SWCNT) coated fiber Bragg grating (FBG). The principle behind which is to produce a dynamic thermal equilibrium between the light heating and the airflow cooling. For the first time, to the best of our knowledge, a 45°-TFG is used as the heating element for the hot-wire anemometer. By diagnosing the Bragg wavelength of the SWCNT coated FBG, the temperature variations of the sensing fiber are measured with respect to the airflow velocities, which vary from 0 to 1 m/s. Moreover, under low light power consumption of 20 mW, the proposed sensor is shown to have good performance. Experimental results reveal that the sensitivity of the sensor increases with the heating pump. Due to the advantages of its simplicity and reliability, alongside its high photo-thermal conversion efficiency, this technique has excellent potential for future use in remote monitoring with airflow velocity sensing.
我们提出并通过实验证明了一种基于45°倾斜光纤光栅（TFG）的气流速度传感方法，该方法将45°倾斜光纤光栅与涂覆有单壁碳纳米管（SWCNT）的光纤布拉格光栅（FBG）相结合。其原理是在光加热和气流冷却之间建立动态热平衡。据我们所知，首次将45°倾斜光纤光栅用作热线风速仪的加热元件。通过诊断涂覆有单壁碳纳米管的光纤布拉格光栅的布拉格波长，测量传感光纤相对于气流速度的温度变化，气流速度范围为0至1 m/s。此外，在20 mW的低光功耗下，所提出的传感器表现出良好的性能。实验结果表明，传感器的灵敏度随加热泵的增加而提高。由于其简单可靠的优点以及高光热转换效率，该技术在未来气流速度传感的远程监测中具有出色的应用潜力。
