We report the modeling and designing aspects of different types of photo-acoustic (PA) cell based on the excitation of longitudinal, radial and azimuthal mode using CW and pulse lasers. The results are obtained by employing fluid dynamics equations along with Bessel’s function. The obtained results based on stimulation of longitudinal, radial and azimuthally resonance modes of the Photo acoustic signals in the suitable cavity. This is utilized to design highly efficient low volume PA detector for the spectroscopic studies of different types of atmospheric pollutants. We have also studied the dependence of the excited photo acoustic signals on various parameters such as cell radius, laser power, absorption coefficient, quality factor ‘Q’ along with the first longitudinal, radial, azimuthal mode and the pressure. The simulated results show the linearity of the PA signal with different concentration of the gas sample.