Filtern
Erscheinungsjahr
- 2022 (1)
Dokumenttyp
- Vortrag (1) (entfernen)
Sprache
- Englisch (1)
Referierte Publikation
- nein (1) (entfernen)
Schlagworte
- Fluidic oscillators (1) (entfernen)
Organisationseinheit der BAM
Eingeladener Vortrag
- nein (1)
The majority of ultrasonic devices used for non-
destructive testing in civil engineering require contact with the
surface of the concrete (specimen), which significantly increases
the time required for the measurement. This makes it impractical
for extensive investigation of large-scale structures such as bridge
decks, foundations, or tunnels.
In a pioneering approach, fluidic oscillators are used as contact
free ultrasonic sources to overcome the aforementioned limi-
tations. These robust and cost-effective actuators require only
pressurised air and are ideally suited for harsh environments. At
a constant supply pressure, they generate a continuous mono-
frequent actuation signal. Further, varying the supply pressure
via a fast pressure regulator was found to generate a frequency
modulated signal which enabled time-of-flight measurement with
an added advantage of increased signal to noise ratio. To
demonstrate the feasibility of this novel idea of non-contact
ultrasound, the results of the initial tests are presented.