On the Rayleigh-Taylor instability induced atomization

A new atomization method to destabilize an annular liquid sheet ejected from a gas turbine engine injector, called the Rayleigh-Taylor instability induced atomization (RTA) is proposed. In contrast to the traditional coaxial atomizers, a liquid is allowed to flow through an annular passage in the axial direction and air is allowed to impinge on the liquid sheet in the radial direction. Due to this interaction, the liquid sheet exhibits a radial acceleration that induces the azimuthal instability and forms a ligament via azimuthal modes. Experimentally, we investigated the atomizer performance using a high-speed imaging technique by varying the Bond number. Here, Bond number ( Bo) is defined by the competition between the radial acceleration force and the surface tension force. We observed that the number of ligaments ( N) root formed from the liquid sheet is a strong function of Bo and found that N similar to Bo . The experimental results agree well with the theoretical model and the proposed scaling is valid in the limit of Weber number <= 3.14. Here, Weber number represents the ratio of inertial force in axial direction to the surface tension force. RTA achieves a novel method of ligament formation and it can create a new avenue for the distinct classes of atomizers. (c) 2021 Elsevier Ltd. All rights reserved.