Quantitative and qualitative characteristics assessment of phase velocity measurements technique
Various time-of-flight measurement techniques are widely used in non-destructive testing(NDT)and structural health monitoring(SHM).According to propagating signal amplitude or velocity changes the defects and delaminations in the objects can be detected.However,the ultrasonic guided waves possess a dispersion phenomenon and accurate determination of signal amplitude or velocity is complicated.The technique which evaluates dispersion phenomenon by using one of the time–of–flight measurement methods is proposed in this paper.The technique is based on measurement of the multiple zero–crossing time instances in the signal,and the phase velocity and the equivalent frequency values are obtained.The proposed method enables to relate the measured values of the phase velocity to the different frequency components of the signal and a segment of the dispersion curve is reconstructed.For test of the performance of the proposed measurement algorithm the Lamb wave signals are used.Analytical modelling and experimental results for the A0 and the S0 modes of the Lamb wave have been evaluated by quantitative and qualitative characteristics.Systematic error for given conditions and expanded uncertainty related to reliability of the measurement process was calculated.
Lamb wave dispersion phase velocity measurement uncertainty.
Lina Draudviliene Asta Meskuotiene Liudas Mazeika Renaldas Raisutis
Institute of Ultrasound,Kaunas,University of Technology,Kaunas,Lithuania Institute of Metrology,Kaunas,University of Technology,Kaunas,Lithuania
国际会议
The 21th International Congress on Sound and Vibration(第21届国际声与振动大会)
北京
英文
1-6
2014-07-13（万方平台首次上网日期，不代表论文的发表时间）