Abstract
ABSTRACT In order to explore the reflection behavior of the longitudinal wave component of Acoustic Emission (AELW) of wood and the velocity of the reflected wave, the reflection characteristics of the AELW in the wood of different lengths were studied and proposed a method for calculating the velocity of the reflected wave of the AELW based on the pencil lead break (PLB) test. First, a classic Hanning window-modulated sinusoidal pulse (HSP) signal was used as an AE source to study the reflection behavior of AELW signals in wood. Then, on the basis of the PLB test, a six-layer wavelet analysis was used to reconstruct an AE signal according to the center frequency of the HSP signal. Last, the short-time energy analysis was implemented in a reconstructed AE signal to determine the time of the first reflection. And then its velocity was calculated according to the principle of time-difference-of-arrival (TDOA). The results showed that there were not related in the velocity of the AELW reflected wave, the reflection coefficients and the attenuation rates of the energy to the length. The velocity obtained based on the PLB test and calculated from the reflection behavior could be accurately represented as the velocity of the AELW wave.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
