Absorption and dispersion of low-frequency sound waves in the main cloud layers of Venus

Abstract

We present predictions for the acoustic wavenumbers at low frequencies in the condensational cloud layers of Venus, occurring between 50 and 70 km, approximately. While the general thermodynamics of Earth clouds is well understood, that of Venusian clouds is still a matter of debate. Venus' clouds are formed primarily of H2O and H2SO4 vapors and aqueous sulfuric acid droplets, the fluxes of which are not fully constrained due to the few insitu observations. This study is based on and adapted from the terrestrial model of Baudoin et al. (J. Acoust. Soc. Am. 130, 1142 (2011)). Inside the clouds, the Navier-Stokes equations of continuum fluid mechanics are used for the gaseous (dry + vapor) and liquid phases of H2O and H2SO4, combined with the equations describing the evaporation/condensation processes; the gaseous phase is treated as an ideal gas. Outside the clouds, in the CO2—dominated atmosphere, the van der Waals equation of state is used. [The work was supported by a Grant from the Louisiana Space Consortium (LaSPACE).]