Experimental Study Of Composite Cylinder Damage By Infrared Detection

Composite cylinder is under the action of alternating load for a long period because of its use characteristics.And fatigue damage is one of the points to impact the safety of cylinder.As the fatigue damage of composite cylinder has no obvious deformation on macroscopic morphology,it has brought great difficulties to discover the fatigue damage.Therefore,non-destructive testing technique must be used to detect the defects of composite cylinders.This paper,the damage detection of composite cylinder is studied by infrared thermography non-destructive testing technique.The delamination defect of composite cylinder is selected as the research object,and then the thermal excitation by infrared detection is discussed.Then a suitable thermal stimulation method is used to do the experimental study of delamination defect of composite cylinder by infrared detection.Firstly,through constructing the model of delamination defect of composite cylinder,the infrared simulation analysis of external thermal excitation and internal thermal excitation are carried out by using finite element software COMSOL Multiphysics,and the detection results under different thermal excitation methods are found.In addition,the thermal excitation experiment of composite cylinder by infrared detection is carried out,and the simulation analysis is verified by experiment.And the suitable thermal excitation method for delamination defect of composite cylinder by infrared detection is discussed.Finally,an infrared detection method for delamination defect of composite cylinder is proposed and the experiment platform of composite cylinder fatigue damage is constructed.Then the infrared detection method is verified through taking the experiment of delamination defect of composite cylinder by infrared detection.The results of the infrared simulation analysis of thermal excitation and the thermal excitation experiment show that external thermal excitation and internal thermal excitation can all detect defects effectively,while the internal thermal excitation hasbetter detection result;the results of experiment of delamination defect by infrared detection show that the proposed infrared detection method is feasible.