Numerical approach to absolute calibration of piezoelectric acoustic emission sensors using multiphysics simulations

Abstract

In this paper, the absolute calibration of piezoelectric Acoustic Emission (AE) sensors is developed using multi-physics numerical and experimental models. In this process, two common excitation approaches including laser and pencil lead break (PLB) are used to generate the simulation sources because of their excellent reproducibility and well-established analytical expressions of their source functions. The numerical models include source function, steel plate and piezoelectric sensor model with the details including adhesive layer, wear plate, piezoelectric ceramic, and backing material. The experimental results of four types of AE sensors (true wideband sensor, low and high frequency conventional sensors and low frequency unpackaged sensor) are compared with the numerical results. The numerically obtained calibration curves show good agreement with the calibration curves provided by the manufacturer. The influences of adhesive layer, backing material and sensor size on the sensor response are studied. The uncoupled piezoelectric sensor models indicate that there is no single displacement history that the sensors can be used for calibration. It is shown that the quantitative AE analysis requires the coupled structural and electrical models of structural medium and piezoelectric sensor.

The Influence of Sensor Size on Acoustic Emission Waveforms—A Numerical Study

“…More specifically, wave energy arrives vertically to the long sensor only in its center, but part of the energy arrives in slightly different angles at the sensors edges due to spreading. The above agrees with recent literature, stating that when the sensor diameter increases, the displacement distribution along the diameter becomes non-uniform [22]. This is not the case for smaller size sensors at which the whole energy arrives vertically and the wave front shape effect is negligible.…”

A Method to Decompose the Streamed Acoustic Emission Signals for Detecting Embedded Fatigue Crack Signals

“…WD sensor has wideband response spanning 100 kHz to 1 MHz; micro 30 sensor has the bandwidth of 150-400 kHz. The resonant behaviors of the AE sensors significantly influence the output signal [15]. Figure 1c shows the calibration curves of WD and micro 30 sensors.…”

“…Time-dependent approach independent from threshold is implemented to record the AE data. The streamed AE waveforms with 150 ms duration and 2 MHz sampling rate are recorded at every 5 s. The resonant behaviors of the AE sensors significantly influence the output signal [15]. Figure 1c shows the calibration curves of WD and micro 30 sensors.…”

Modelling of Acoustic Emission Signals Due to Fiber Break in a Model Composite Carbon/Epoxy: Experimental Validation and Parametric Study

“…For the signal detection, some analytical approaches considered the sensors transfer function explicitly. Some authors [39][40][41][42][43] have proposed a finite element approach to include the piezoelectric sensor in a modelling environment in order to take into account the interface between the sensor and the material.…”