Highly non-linear sensing devices in structural health monitoring

Pfeiffer, Helge; KU Leuven; Belgium

Pfeiffer, H.; University of Leuven; Belgium
Sekler, H.; University of Leuven; Belgium
Sunetchiieva, S.; University of Leuven; Germany
Wevers, M.; University of Leuven; Belgium

ID: ECNDT-0594-2018
Session: Process Control 2
Room: R2
Date: 2018-06-12
Time: 13:30 - 13:50

During the daily aircraft operation, water accumulation in fuel tanks by condensation and contaminated fuel cannot be prevented. While the “free water” [Banea, 2013] potentially leads to microbial corrosion and the misreading of fuel meters, freezing water can harm the internal structure of the fuel tank in a high degree resulting in potentially hazardous situations for passengers, crew members and ground personnel.

Water is drained outside the fuel tank whenever possible. However, this procedure only reduced the amount of liquid water in the tank and is not applicable on ice in the tank. And even after the procedure, the remaining water in the tank cannot be estimated. Up to now, there is no generally accepted “non-invasive” method available to determine the amount of water and ice in the tank.

The detection of the “damage mode” water/ice in the tank is an ideal field of application for diverse advanced acoustic, ultrasonic and thermal NDT methods which tested to estimate the location and volume of water and ice in the tank. First experiments showed the applicability of active and passive acoustic as well as thermal measurements for the detection of melting ice on plate-like structures.

Advanced experiments are performed on a tank model made from the materials comparable to the aircraft tank (material, thickness, coatings, etc.). To simulate realistic conditions, kerosene and water are cooled down as present in the fuel tank. Results show that ultrasonic and thermal image measurements are applicable for the localization of subsurface ice in the tank filled with kerosene.

Research leading to these results has received funding from the “NDTonAIR” project (Training Network in Non-Destructive Testing and Structural Health Monitoring of Aircraft structures) under the action: H2020-MSCA-ITN-2016-GRANT 722134.