Monitoring Method Of Structure Thermal Properties And Deformation Based On Optical Fiber

Under the complex environment of multiple physical field serving for a long time,it is easy for Aerospace structures to be affected by extreme temperature and external forces,which can induce structural changes,resulting in a decrease in the safety and reliability of the structure.Therefore,it is of great significance to carry out research on the thermal properties and deformation monitoring of structures.Thus,this paper studies the structural thermal property monitoring method and structural form sensing and reconstruction algorithm based on fiber optic sensing technology,and provides support for real-time monitoring and analysis of structural health status.The main research work includes the following aspects:Firstly,the integration method of optical fiber grating sensor network with measure structure object is studied.The sensing test system of carbon fiber composite material and aluminum alloy plate adhesive structure is constructed by the method of implantable adhesive grafting based on distributed optical fiber sensor,those works could provide the basis for the application of the subsequent implantable method to monitor aerospacecraft bonding structure change state.Secondly,aiming at the situation that thermal cycle load effect acts on space structure and affects the function and safety of spacecraft,measuring technology of the plate structure thermal strain and deformation based on distributed fiber optical sensors is carried out.Additionally,an aluminum alloy plate thermal expansion coefficient calculating method based fiber optical strain transfer matrix is also proposed,and the feasibility of the method is verified.Thirdly,the thermal strain measurement technology of the carbon fiber board structure based on distributed optical fiber sensor is researched.Based on thermal strain monitoring,the thermal expansion coefficient of the composite material plate is calculated through the optical fiber strain transformation matrix calculation method,the thermal properties monitoring of carbon fiber composite materials plate under high and low thermal cycle load structure is realized.Finally,according to the deformation sensing and real-time monitoring demand of aerospace structure,the space surface reconstruction algorithm based on orthogonal curvature is studied.The feasibility of the algorithm is applied to structural deformation monitoring is verified by the numerical simulation and test.At the same time,developed real-time monitoring visualization system of the three-dimensional shape based on the LabVIEW,and real-time monitoring and health board structure deformation analysis is realize.