  We study the thermo-acoustic wave propagation and reflection near the
liquid-gas critical point. Specifically, we perform a numerical investigation
of the acoustic responses in a near-critical fluid to thermal perturbations
based on the same setup of a recent ultrasensitive interferometry measurement
in CO2 [Y. Miura et al. Phys. Rev. E 74, 010101(R) (2006)]. The numerical
results agree well with the experimental data. New features regarding the
reflection pattern of thermo-acoustic waves near the critical point under pulse
perturbations are revealed by the proper inclusion of the critically diverging
bulk viscosity.
