Numerical Analysis of a ‘T’ Type Resonant Photoacoustic Cell

Abstract

In this work, we have numerically studied the effect of geometrical parameters on the photoacoustic response of a ‘T†type resonant photoacoustic cell, in which laser passes through one cylinder, known as absorption cylinder and the resonance is targeted in another cylinder, which is called as resonator, arranged perpendicular to the absorption cylinder. For the study, we solve linearized forms of the continuity equation, Navier-Stokes equation, energy equation, and equation of state using a finite element method (FEM) based software. It is found that the simultaneous excitation of resonance in both resonator and the absorption cylinder reduces the amplitude of acoustic response at the position of microphone. To avoid this, the length of absorption cylinder should not be an exact multiple of the length of resonator.