Excitation of Acoustic Vibrations during Combustion of Droplets of Liquid Fuel

A theoretical investigation is performed of the excitation of acoustic vibrations during combustion of droplets of liquid fuel. The droplets are taken to be monodisperse, spherical, and stationary with respect to gas away from the droplets. It is assumed that the combustion of droplets proceeds in the diffusion mode. The binary diffusion coefficients are taken to be the same and independent of the concentration of the gas mixture components, and the Lewis number is taken to be unity. In determining the conditions of excitation of acoustic vibrations, the gas mixture is treated as perfect gas. Expressions are derived for the frequency and increment of excitation of acoustic vibrations, which explicitly include the characteristics of fuel and oxidizer.