title: Numerical modeling of the sound propagation through a rarefied gas in a semi-infinite space on the basis of linearized kinetic equation.
abstract: The sound propagation through a rarefied gas is investigated on the basis of the linearized kinetic equation. A plate oscillating in the direction normal to its own plane is considered as a sound wave source. It is assumed a fully established oscillation so that the solution of the kinetic equation depends on time harmonically, while its dependence on the spatial coordinates is obtained numerically. The problem is solved over a wide range of the oscillation speed parameter defined as a ratio of the intermolecular collision frequency to the sound frequency. In order to evaluate the influence of the momentum and energy accommodation coefficients on the solution of the problem, the Cercignani-Lampis scattering kernel is applied as the boundary condition. An analysis of wave characteristics near the source surface shows that they are significantly different from those far from the surface even if the oscillation is slow, i.e., the solution is not harmonic in the space.
authors.affiliation: Departamento de Fisica, Universidade Federal do Parana, Caixa Postal 19044, Curitiba 81531-990, Brazil. sharipov@fisica.ufpr.br
authors.forename: Felix
authors.initials: F
authors.lastname: Sharipov
authors.forename: Denize
authors.initials: D
authors.lastname: Kalempa
mesh_terms: D000162:Acoustics; D003198:Computer Simulation; D007700:Kinetics; D016014:Linear Models; D008962:Models, Theoretical; D009038:Motion; D005741:Noble Gases; D009716:Numerical Analysis, Computer-Assisted; D009991:Oscillometry; D011312:Pressure; D013016:Sound; D013814:Thermal Conductivity; D014783:Viscosity
chemical_list: D005741:Noble Gases