Abstract: The third part of the guided wave based structural health monitoring of pressure vessel applies the aforementioned structural health monitoring technology in the damage localization of a filament wound pressure vessel. The hydraulic fatigue cycling and pressurization experiments of a full-scale composite pressure vessel are performed, and the damage localization results are transferred by a remote monitoring system. The guided wave signal as well as the strain of the tank and the composite layer during the mechanical tests are obtained, and the relationship between the amplitude of the guided wave signal and the fatigue and pressurization status of the pressure vessel are built. During the pressurization, the damage localization is performed by the system under different pressures, and the damage localization accuracy is analyzed. Results show that the fatigue status of the pressure vessel can be reflected by the strain, however, the strain tendency cannot reflect its status after fatigue. The amplitude of the guided wave decreases linearly with the fatigue cycles. After fatigue for 5 700 cycles, the amplitude decreasing with the inner pressure, while the strain shows an increasing tendency. Relationship between the two parameters could be used to measure the pressure vessel status. Fatigue affect the damage localization accuracy sharply, while the developed remote monitoring system could get the damage information of the filament wound pressure vessel before fatigue with high accuracy.

Key words: filament wound pressure vessel, guided waves, remote monitoring, hydraulic fatigue, bursting