Novel integrated optical fiber sensor for temperature, pressure and flow measurement

A novel integrated optical fiber sensor was proposed for temperature, pressure and flow measurement. One fiber Bragg grating (FBG) was fixed in the target for temperature measurement. A couple of FBGs, which were stuck on the inner wall of a hollow cylindrical cantilever, were used to measure flow rate. Another couple of FBGs were fixed on the outer wall of a thin-walled cylinder to measure pressure. Theoretical relationships between the Bragg wavelengths of FBGs and temperature, pressure and flow rate, have been established by numerical analysis respectively. Meanwhile, experiments have been carried out to obtain the performance of the proposed integrated sensor. Experimental results showed that the resolutions of temperature, pressure and flow rate were 0.1 °C, 0.006 MPa, 0.17m3/h and the measurement ranges were 10∼95 °C, 0∼10 MPa and 0∼18.5m3/h, respectively. In addition, the precision of sensor in temperature, pressure and flow rate were 0.12%, 0.5%, 1.5%, respectively. As we know, the proposed flowmeter is more compact with good resolution, wide measurement range, high accuracy and easy fabrication.