報告題目：Beam Damage Uncertainty Quantification Using Guided Lamb Wave Responses
報告人：Dr. Gang Wang（ Department of Mechanical and Aerospace Engineering University of Alabama in Huntsville, Huntsville, AL, USA）
報告時間：2016年6月16日15:00
報告地點：A18-529
主辦單位：國際交流合作處、科協、航空宇航學院
Abstract: A Bayesian inference approach is developed to conduct uncertainty quantification on the notch damage in a beam structure using guided Lamb wave responses. The proposed methodology not only determines the notch damage characteristics (i.e., location and extent) but also quantifies associated uncertainties of these inferred values. Thus, such information is essential for decision-making in the structural health monitoring (SHM) applications. First, a spectral finite element model is used to characterize Lamb wave propagation responses in a beam under PZT actuation and sensing. Very few elements are required to accurately capture the wave propagation. The PZT sensor can pick up the reflected wave responses from both boundaries and damages. Total 18 simulation cases were generated by varying notch damage extent, damage location, and noise level. Secondly, the Markov Chain Monte Carlo (MCMC) techniques are employed to estimate the notch damage location and extent from guided Lamb wave responses, in which the random walk Metropolis algorithm is used. Finally, both crack size/location and associated uncertainties are characterized. In summary, the proposed probabilistic damage detection is successfully demonstrated in beam structures using the guided wave responses, which can be extended to other SHM applications.
Biography: Dr. Gang Wang is an Associate Professor in the Department of Mechanical and Aerospace Engineering (MAE) at the University of Alabama in Huntsville (UAH).Dr. Wang received MS and PhD degrees in Aerospace Engineering from the University of Maryland, College Park, in 1998 and 2001, respectively, and BS and MS degrees in Engineering Mechanics from Dalian University of Technology, Dalian, China in 1993 and 1996, respectively. His areas of research include structural dynamics, adaptive structures, rotorcraft, and structural health monitoring. He has authored more than 50 archival journal and conference papers and awarded 3 US patents.
He is currently an Associate Fellow of the American Institute of Aeronautics and Astronautics (AIAA) and a member of the American Society of Mechanical Engineers (ASME) and the American Helicopter Society (AHS).
