Instability of cylindrical compressible gas jets in viscous liquid streams
We examine a linear stability of cylindrical compressible gas jets in a moving incompressible viscous liquid medium subject to varicose disturbances. It is found that the gas jet is always unstable in a range of wavenumbers under any flow condition. When the gas and liquid velocity are not equal, temporal instability is enhanced by surface tension effects at small Weber numbers, and by aerodynamic interaction between the gas and liquid at high Weber numbers (where surface tension has a stabilizing influence). Increasing liquid viscosity always reduces the growth rate and the dominant wavenumber, whereas increasing gas density always increases gas jet instability. It is also found that the relative, rather than the absolute, velocity of the gas and liquid controls temporal instability.
aerodynamic interaction between gas and liquid
scientific article; zbMATH DE number 1203591
scientific article