Out of longitudinal, torsional, lamb wave modes etc ( L(0,1) , L(0,2), S0.........); which are the efficient modes that can be used for the sensing applications mentioned above.
If there are any modes, what is its advantage over other?
I am not sure your question is well posed. Temperature mostly affects sound velocity. So you should manipulate an observable that is sensitive to velocity such as travel time, for example. Similarly, a change in viscosity or density mostly affects amplitude so, again, your observable should be adjusted to the wavefield amplitude. To my opinion, your capacity to measure viscosity, temperature or density will rely more on the observable you choose than the type of mode you excite.
Thanks Philippe. So it means even if we use any particular wave mode we can use its time of flight to determine the temperature; and amplitude to determine viscosity/density right???...
yes, Subhash, I would say so. On the other hand, it is important to keep in mind the mode shape (also called modal deformation) in the medium of interest. If you aim at detecting a defect at the surface of an object with a mode that has a zero at the surface, it won't work. But this aspect is separate from the observable you use. To optimize detection / localization, you must then combine : (1) the good mode or set of modes that shows sensitivity at the placeyou expect a change to occur andd (2) the good observable (time of flight or amplitude, for example) that will correxpond to the nature of the perturbation you expect (sound speed or density).
- Badges
- Science topic
- Similar topics
- Mathematical Sciences
- Graphs