Fourth International Engineering Research Symposium (INERS'22), Düzce, Turkey, 4 - 06 March 2022, pp.60
We develop a theoretical
framework describing numerical approach to explore dynamic acoustic force
sensitivity using micro-cantilever array in monomodal and bimodal operations.
The excitation force at second eigenmode frequency is supplied to the
micro-cantilevers in monomodal operation. Since we focus on measurement
sensitivity of acoustic forces at higher frequencies, deflections of micro-cantilevers
at higher mode, second flexural mode, are obtained. In bimodal operations,
external driving forces at the first and second eigenmode frequencies are
applied simultaneously for actuation of micro-cantilevers in array. Depending
on acoustic force strength, application of driving force at higher eigenmode
frequency in bimodal excitation scheme increases the phase sensitivity in
measurement of acoustic forces within a particular frequency scope. For both
excitation schemes, oscillation observables such as amplitude and phase shift are
determined with respect to acoustic force frequencies for diverse acoustic
force strengths. Simulation results suggest that wider high-sensitivity
frequency band could be acquired, utilizing resonantly excited micro-cantilever
array. For our case, we obtain the high-sensitivity frequency band of around
200-270 kHz and 440-570 kHz for the acoustic force strengths in the range of
126 - 1138.5 pN.