Research On Ice Detection Based On Lamb Wave

In recent years,flight safety issues caused by aircraft icing have received widespread attention in the aviation field,and ice detection has always been an important part of research in the field of aircraft anti-icing.Ultrasonic guided wave detection has the advantages of being able to detect large-scale test pieces,fast detection speed,and long-distance propagation.This paper mainly focuses on the parameter selection,identification algorithm and experimental verification of ultrasonic detection of ice on the surface of the wing.The specific research content is as follows:Based on the basic equations of elastic theory,the propagation characteristics of Lamb wave in isotropic media are discussed,the theoretical model of Lamb wave propagation in free plates is established,the dispersion equation of Lamb wave is derived,and the propagation problem of Lamb wave in multilayer material plates is analyzed.Aiming at the problem of icing on aluminum alloy plates,a double-layer model of ice and aluminum alloy plates is established,and the dispersion curve of icing on aluminum alloy plates is given.The numerical model of Lamb wave propagation based on icing on aluminum alloy plates is established and verified.The influence of icing on the dispersion curve of Lamb wave is studied.The influence of icing on Lamb wave propagation on aluminum alloy plates is analyzed,and the influence of ice thickness and ice length on Lamb wave propagation characteristics is given.The parameters needed for the experimental study are determined by numerical simulation,such as center frequency,Lamb wave mode,excitation waveform,etc.The positioning algorithm of Lamb wave ice detection is studied.The corresponding program is written with Matlab software platform,the test platform for ice detection is built,and the aluminum alloy plate ice detection verification test is carried out.The influence of the number of sensors,the arrangement of sensors,the shape of ice,the area of ice and the thickness of ice on the detection effect are discussed.Finally,the ice detection test is carried out on the intercept model of NACA2415 airfoil,and the identification of ice position is completed,which verified the feasibility of the detection technology.