Modeling Frequency Response of Photoacoustic Cells using FEM for
Determination of N-heptane Contamination in Air: Experimental Validation
Lars Duggen, Mihaela Albu, Morten Willatzen, Horst-Günter Rubahn
We briefly present the basic principle of the photoacoustic effect
in gases. We present the equations and boundary conditions governing
the acoustic field generated by the absorption of a modulated
laser beam. We solve these equations using Finite Element
Methods and compare the results with experiment. We find that
apparently there are effects not taken into account in the classic
acoustic theory as we find a larger damping than theory predicts.
However, we see that these effects have significant negative influence
on the quality factor of the cell and thereby the performance
limit. Full Text
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