Regarding the role of second viscosity in rarefied gas dynamics

Using the exemplar problem of a rarefied gas flow around an inclined plate with M = 20, the issues of correctly taking into account the effects that arise during the flow of rarefied gas, in particular, second (bulk) viscosity effects, are considered. A brief overview of the current state of studies of second viscosity of gases is given. The results of calculations using the Navier–Stokes equations and quasi-gasdynamic equations are presented and analyzed. A conclusion is made about the significant influence of second viscosity on the results of rarefied gas flow simulations, regardless of the system of dynamics equations utilized.