Presentazioni e Articoli Tecnici

Among optical gas sensing methods, photoacoustic (PA) spectroscopy combined with a laser source has proven to be a very robust and sensitive method for trace gas detection. COMSOL Multiphysics® software was used to calculate the frequency response of differential Helmholtz resonator cells in order to optimize the detection limit of PA sensors. Two different kind of simulation were performed: Resolution of the heterogeneous Helmholtz equation using eigenfrequencies determination in the Pressure Acoustics, Frequency Domain interface and computation of frequency response using an expansion on the eigenmodes. We will present comparisons between experimental determination of the cell frequency response and the two kinds of simulation performed using COMSOL Multiphysics®. The influence of mesh characteristics will be discussed.