Ultraschallbasiertes Sensorprinzip für die eingriffsfreie Messung des hydrostatischen Drucks

Description

In this work, a sensor principle for measuring the static mechanical stress in the pipe wall and thus the hydrostatic pressure based on guided elastic waves is developed. The aim is to use signal components running parasitically in the pipe wall in new flow sensors that are based on the targeted excitation of guided elastic waves in the pipe wall. Ideally, this would eliminate the need to install additional sensors.
To model the measuring principle, an efficient method for solving the linear boundary value problem of guided wave propagation was implemented and the influence of static mechanical stress based on the acoustoelastic effect was integrated.
Another focus of the work is the metrological verification of the implemented models and the empirical proof of the usability of the effect for measuring the hydrostatic pressure. Both transmitter-receiver measurements, as envisaged by the developed sensor principle, and multi-channel measurements at distributed receiver locations using a laser Doppler vibrometer were carried out. The accuracy of the models was improved by a specially developed inverse material characterization method. A new approach for the inverse characterization of third-order elasticity constants was also developed. The new sensor principle was successfully demonstrated.