Development Of CFRP Encapsulated Ribbon Optical Fiber Sensor

Carbon Fiber Reinforced Plastics(CFRP)has been widely used in aerospace,civil engineering,and other fields because of its high specific strength and specific modulus,and its ease of molding.Based on distributed optical fiber sensing technology,this dissertation focuses on the research of making fiber-optic fiber sensor with sensing function by implanting fiber into carbon fiber composite material.It can be used for long-distance and large-scale distributed temperature and strain measurement.The main content of the paper includes the following aspects:Firstly,comparing and analyzing the different methods of fiber optic sensor packaging,combined with the design requirements of distributed and temperature-strain separation,it was determined to use hot-pressing and vacuum bag method respectively.Secondly,the CFRP ribbon optical fiber sensor packaging technology was explored,and the cross-sensitivity of the fully distributed optical fiber sensor was solved by the slack fiber technology.The fiber placement scheme of laying the relaxed fiber and the tension fiber in sections was designed.The Teflon capillary and rod were used.To achieve temperature,strain+ temperature of the modular sensing;the best sensing performance of the fiber for the purpose of optimizing the carbon fiber prepreg thermal parameters,including heating and pressing time,temperature,pressure size.Thirdly,the sensor performance of the ribbon fiber sensor in CFRP package was analyzed.A 1285mm×400mm×10mm equal-strength beam was designed and fabricated.the geometric model of the cantilever beam with CFRP ribbon fiber sensor was established and applied to ANSYS finite element software.The strain response at different static loads was analyzed and compared with the cantilever's theoretical strain value to evaluate sensor performance.Fourthly,An Optical Frequency-Domain(OFDR)ribbon optical fiber sensor performance test system was set up to carry out temperature and temperature-strain loading experiments,respectively,by suspending weights and hot air source loading at the free end of the cantilever beam.The temperature and strain sensing performance of the specification and ribbon fiber sensor were tested,and the measurement results were compared with those of the thermal thermocouple wire and the strain gauge.The magnitude of the error was calculated and thesource of the error was analyzed.The results show that the fabricated CFRP ribbon optical fiber sensor has better temperature and strain sensing performance...